Co-reporter:Dan Zhu, Wei Liu, Dongxia Zhao, Qing Hao, Jing Li, Jiaxuan Huang, Jiye Shi, Jie Chao, Shao Su, and Lianhui Wang
ACS Applied Materials & Interfaces October 18, 2017 Volume 9(Issue 41) pp:35597-35597
Publication Date(Web):September 26, 2017
DOI:10.1021/acsami.7b11385
Herein, we demonstrated a label-free and simple electrochemical sensing platform to detect microRNA-21 (miR-21) with high sensitivity by using MoS2 nanosheet functionalized with thionine and gold nanoparticles (MoS2-Thi-AuNPs). Interestingly, thionine (Thi) was used as a reducing agent to successfully synthesize MoS2-Thi-AuNPs nanohybrid and as a signaling molecule to monitor DNA-RNA hybridization, which provided an ideal platform for label-free miR-21 detection. Upon hybridization with miR-21, the formation of the DNA-RNA duplex on the electrode would greatly hinder the electron transfer, which caused the electrochemical signal decrease of Thi. After optimization of experimental conditions, the signal change of peak currents of Thi has a linear relationship with the logarithm of miR-21 concentration ranging from 1.0 pM to 10.0 nM and the limit of detection (LOD) was 0.26 pM. Moreover, this biosensor could detect miR-21 in biological samples like human serum with satisfactory results.Keywords: electrochemical biosensor; gold nanoparticles (AuNPs); microRNA; molybdenum disulfide (MoS2); thionine (Thi);
Co-reporter:Shao Su, Xiaoyan Han, Zaiwei Lu, Wei Liu, Dan Zhu, Jie Chao, Chunhai Fan, Lihua Wang, Shiping Song, Lixing Weng, and Lianhui Wang
ACS Applied Materials & Interfaces April 12, 2017 Volume 9(Issue 14) pp:12773-12773
Publication Date(Web):March 22, 2017
DOI:10.1021/acsami.7b01141
Herein, an electrochemical detection platform was designed based on a Prussian blue nanocube-decorated molybdenum disulfide (MoS2-PBNCs) nanocomposite. Shape-controlled and high-dispersion PBNCs were supported on the MoS2 nanosheet surface, which would be simply controlled by varying the experimental conditions. Expectedly, such obtained MoS2-based nanocomposites possessed excellent electrocatalytic ability, which could be employed to construct an electrochemical sensor for nonenzymatic hydrogen peroxide (H2O2) detection. More interestingly, MoS2-PBNCs nanocomposites could be utilized to construct a sensor for label-free detection of carcinoembryonic antigen (CEA). The electrochemical response of the MoS2-based immunosensor was linear with the CEA concentration ranging from 0.005 to 10 ng mL–1. Moreover, the detection limit was calculated to be 0.54 pg mL–1. The acceptable selectivity and high stability made such immunosensors detect CEA in human serum with satisfactory results. All data indicated that this MoS2-PBNCs nanocomposite may be a promising electrochemical sensing platform for the detection of chemical and biological molecules.Keywords: electrochemical sensor; label-free; Molybdenum disulfide; nonenzymatic; Prussian blue nanocubes;
Co-reporter:Yanjun Yang 杨琰君;Xinyu Jiang 蒋新宇;Jie Chao 晁洁;Chunyuan Song 宋春元
Science China Materials 2017 Volume 60( Issue 11) pp:1129-1144
Publication Date(Web):09 May 2017
DOI:10.1007/s40843-017-9022-1
Magnetic core gold shell nanostructures which integrate both SERS activity and superparamagnetism are widely utilized in SERS-based detection as SERS substrates, sample separation and preconcentration operators, as well as external magnetic field controlled directional carrier. However, most of the reported gold shells coated on the magnetic cores had smooth surfaces rather than branched nanostructures with enhanced SERS activity. Here, a novel type of Fe3O4-Au core-shell nanoparticles with branched gold shell was prepared by a seed-mediated method together with the shape induction agent AgNO3, and their growth process and mechanism, properties, as well as morphologically controlled synthesis were also investigated. The branched gold coated magnetic nanoparticles (B-GMNPs) with improved SERS performance were further utilized to build superparamagnetic and SERS-active capturers by assembling tetrahedral DNA onto their surfaces for sandwich-structured detection of cancer-related biomarker miRNA-21. The experimental results indicate that highly sensitive and specific detections can be obtained by the proposed SERS sensing system including B-GMNPs and tetrahedral DNA, and the limit of detection (LOD) of miRNA-21 in serum is 623 amol L−1. These B-GMNPs can be used as good SERS substrates with the functions of external magnetic field controlled sample separation and directional enrichment for effective SERS-based biochemical sensing and detections.复合SERS活性和超顺磁性的磁核金壳纳米颗粒在SERS传感、样品分离与富集、定向输运等方面已有广泛应用. 已报道的基于磁 核制备的金纳米壳大多为平滑的金壳, 基于磁核生长枝杈状金壳可以提升颗粒的SERS增强性能, 但相关报道甚少. 本文基于种子生长法 并引入定向生长控制剂AgNO3, 合成了一种新型的磁核枝杈状金壳纳米颗粒, 系统地研究了金壳的生长过程与机制、表面形貌的控制生 长以及对SERS性能的影响. 此外, 设计并构建了具有良好的结构刚性、稳定性和空间定位能力的四面体DNA探针, 并将其修饰到磁核枝 杈状金壳纳米颗粒表面构建得到检测基底. 通过在金纳米颗粒表面修饰单链DNA构建SERS探针, 利用碱基互补配对形成“检测基底-目标 核酸-SERS探针”三明治结构复合物, 借助外加磁场分离检测液中的复合物并富集后进行SERS检测, 实现了对于血清中肿瘤核酸标志物 miRNA-21的高灵敏、特异性检测, 检测限达到623 amol L−1.
Co-reporter:Nina Fu, Suiliang Wang, Yuqian Zhang, Caixia Zhang, Dongliang Yang, Lixing Weng, Baomin Zhao, Lianhui Wang
European Journal of Medicinal Chemistry 2017 Volume 136(Volume 136) pp:
Publication Date(Web):18 August 2017
DOI:10.1016/j.ejmech.2017.05.001
•1-alkyl 1H-1,2,3-triazole-4-carboxylic acids (ATCs) have been explored as Novel anti-fungal inhibitors for C. albicans•This two-step in one-pot strategy can be extended to multiple function anti-fungal drugs.•5c and 5d both showed advanced medicinal activity in vitro.•Medicinal effects and structural relationship of 1,2,3-triazole moiety has been identified.Candida is an important opportunistic human fungal pathogen. The cis-2-dodecenoic acid (BDSF) showing in vitro activity of against C. albicans growth, germ-tube germination and biofilm formation has been a potential inhibitor for Candida and other fungi. In this study, facile synthetic strategies toward a novel family of BDSF analogue, 1-alkyl-1H-1,2,3-triazole-4-carboxylic acids (ATCs) was developed. The straightforward synthetic method including converting the commercial available alkyl bromide to alkyl azide, consequently with a typical click chemistry method, copper(II) sulfate and sodium ascorbate as catalyst in water to furnish ATCs with mild to good yields. According to antifungal assay, 1-decyl-4,5-dihydro-1H-1,2,3-triazole-4-carboxylic acid (5d) showed antifungal capability slightly better than BDSF. The 1,2,3-triazole unit played a crucial role for the bioactivity of ATCs was also confirmed when compared with two alkyl-aromatic carboxylic acids. Given its simplicity, high antifungal activity, and wide availability of compounds with halide atoms on the end part of the alkyl chains, the method can be extended to develop more excellent ATC drugs for accomplishing the challenges in future antifungal applications.Two-steps in “one-pot” synthesis of ATC compounds, BDSF analogues, for efficient application as anti-fungal agents. The design, synthesis and bioactivity performance were all described.Download high-res image (136KB)Download full-size image
Co-reporter:Yuqian Zhang;Weijun Xiu;Yiting Sun;Di Zhu;Qi Zhang;Lihui Yuwen;Lixing Weng;Zhaogang Teng
Nanoscale (2009-Present) 2017 vol. 9(Issue 41) pp:15835-15845
Publication Date(Web):2017/10/26
DOI:10.1039/C7NR05278B
The fast-developing field of nanotechnology provides unprecedented opportunities for the increasing demands of biomedicine, especially for cancer diagnostics and treatment. Here, novel multifunctional zero-dimensional-two-dimensional (0D–2D) RGD-QD-MoS2 nanosheets (NSs) with excellent fluorescence, photothermal conversion, and cancer-targeting properties were successfully prepared by functionalizing single-layer MoS2 NSs with fluorescent quantum dots (QDs) and arginine–glycine–aspartic (RGD) containing peptides. By using RGD-QD-MoS2 NSs as a multifunctional theranostic agent, targeted fluorescent imaging and photothermal therapy (PTT) of human cervical carcinoma (HeLa) cells were achieved. Moreover, HeLa tumors in mouse models can be fluorescently imaged and completely eradicated by photothermal irradiation using a low power NIR laser, due to the effective accumulation of RGD-QD-MoS2 NSs at the tumor sites through the RGD-integrin targeting and the enhanced penetration and retention (EPR) effect. Without exhibiting any appreciable toxicity to treated cells or animals, RGD-QD-MoS2 NSs have been demonstrated as promising multifunctional theranostic agents for cancer imaging and therapy.
Co-reporter:Meng Dang;Wei Li;Yuanyi Zheng;Xiaodan Su;Xiaobo Ma;Yunlei Zhang;Qianqian Ni;Jun Tao;Junjie Zhang;Guangming Lu;Zhaogang Teng
Journal of Materials Chemistry B 2017 vol. 5(Issue 14) pp:2625-2634
Publication Date(Web):2017/04/05
DOI:10.1039/C6TB03327J
Mesoporous organosilica nanoparticles (MONs) have attracted increasing interest for guest molecule delivery. In this work, we prepared MONs with radially oriented large pores for the first time in a water–ethanol/n-hexane biphasic reaction system. The MONs possess ethane-incorporated organosilica frameworks, large radial pores with openings of 17–78 nm, a high surface area (1219 cm2 g−1), a large pore volume (2.2 cm3 g−1), tunable diameters (124–287 nm), and excellent biocompatibility. We reveal that the formation of large pore MONs in the biphasic reaction system undergoes a surfactant-directed self-assembly following mesostructure reconstruction, providing a new mechanism for the preparation of large mesoporous nanoparticles. Also, the effects of the reaction parameters including temperature and the stirring rate on the pore size are systemically investigated. Furthermore, large pore MONs were loaded with bovine serum albumin (BSA) and small interference RNA (siRNA), which exhibit high protein loading and siRNA delivery capabilities, suggesting the potential of the MONs for biomedical applications.
Co-reporter:Yu Gao;Yiyuan Han;Mingyue Cui;Hong Liang Tey;Chenjie Xu
Journal of Materials Chemistry B 2017 vol. 5(Issue 23) pp:4535-4541
Publication Date(Web):2017/06/14
DOI:10.1039/C7TB00664K
Tissue adhesives have emerged as alternatives to suturing and stapling in the treatment of reconnection of injured tissues. They can be accurately applied to the regions of body that are not easy to access in a minimally invasive way without a high level of training. Recently, it was demonstrated that nanoparticles can directly glue hydrogels or tissues without the need for in situ polymerization or crosslinking. For example, silica nanoparticles can serve as connectors between tissues and exhibit adhesion even in the presence of blood. This work reports the adhesive effect of two antimicrobial nanoparticles, i.e. titanium dioxide and zinc oxide nanoparticles, between hydrogels, hydrogel/polymer, and liver tissues. These two nanoparticles exhibit comparable or even better adhesive effects in comparison to silica nanoparticles. In a skin wound mouse model, zinc oxide nanoparticles achieve successful wound closure and aesthetic wound healing, suggesting their capability as an effective antimicrobial tissue adhesive.
Co-reporter:Yu Gao;Ammar Mansoor Hassanbhai;Jing Lim;Chenjie Xu
RSC Advances (2011-Present) 2017 vol. 7(Issue 17) pp:10051-10056
Publication Date(Web):2017/02/03
DOI:10.1039/C6RA26063B
This work investigated the antimicrobial activity of Ag octahedral nanoparticle containing polycaprolactone scaffolds (Ag–PCL) that is fabricated via cryomilling. The fabricated composite scaffolds exhibited localized antibacterial activity with no adverse effects on viability and osteogenic differentiation of human fetal mesenchymal stem cells (hfMSCs). Compared to plain PCL scaffolds, the Ag–PCL scaffolds significantly reduce bacteria survival to 32.2% over a 4 hour incubation.
Co-reporter:Yikang Xing;Bing Liu;Jie Chao
RSC Advances (2011-Present) 2017 vol. 7(Issue 75) pp:47425-47434
Publication Date(Web):2017/10/06
DOI:10.1039/C7RA09781F
The rapidly growing field of nanodevices is attracting more and more attention on account of their ingenious design and broad application. Taking advantage of the sequence specificity and excellent programmability of DNA molecules, numerous DNA devices with multiple functions have been designed and fabricated such as tweezers, gears, cranes and so on. DNA walking devices are the most sophisticated ones either in design or fabrication. They exhibit a powerful ability to actuate walkers walking on their tracks. Herein we review DNA walking devices based on walking functions including unipedal, bipedal, multipedal, and other novel walking devices, as well as their applications.
Co-reporter:Yanling Hu;Ying Huang;Chaoliang Tan;Xiao Zhang;Qipeng Lu;Melinda Sindoro;Xiao Huang;Wei Huang;Hua Zhang
Materials Chemistry Frontiers 2017 vol. 1(Issue 1) pp:24-36
Publication Date(Web):2016/11/30
DOI:10.1039/C6QM00195E
Biosensors are powerful tools used to monitor biological and biochemical processes, ranging from clinical diagnosis to disease therapy. The huge demands for bioassays greatly promote the development of new nanomaterials as sensing platforms. Two-dimensional (2D) nanomaterials with superior properties, such as large surface areas and excellent conductivities, are excellent candidates for biosensor applications. Among them, single- or few-layered transition metal dichalcogenide (TMD) nanomaterials represent an emerging class of 2D nanomaterials with unique physical, chemical, and electronic properties. In this mini-review, we summarize the recent progress in 2D TMD nanomaterial-based biosensors for the sensitive detection of various kinds of targets, including nucleic acid, proteins, and small biomolecules, based on different sensors like optical sensors and electrochemical sensors, and bioelectronic sensors. Finally, the challenges and opportunities in this promising field are also proposed.
Co-reporter:Shao Su, Wenfang Cao, Wei Liu, Zaiwei Lu, Dan Zhu, Jie Chao, Lixing Weng, Lihua Wang, Chunhai Fan, Lianhui Wang
Biosensors and Bioelectronics 2017 Volume 94(Volume 94) pp:
Publication Date(Web):15 August 2017
DOI:10.1016/j.bios.2017.03.040
•A dual-mode electronic biosensor is developed for miRNA-21 detection based on AuNPs@MoS2.•DPV and EIS are used to detected miRNA-21 with high sensitivity and selectivity.•Suitable detection methods for nanomaterials-based biosensor could maximize the detection signal according to the nanomaterials' properties.The detection of microRNA plays an important role in early cancer diagnosis. Herein, a dual-mode electronic biosensor was developed for microRNA-21 (miRNA-21) detection based on gold nanoparticle-decorated MoS2 nanosheet (AuNPs@MoS2). A classical DNA “sandwich” structure was employed to construct MoS2-based electrochemical sensor, including capture DNA, target miRNA-21 and DNA-modified nanoprobe. [Fe(CN)6]3-/4- and [Ru(NH3)6]3+ were selected as electrochemical indicators to monitor the preparation process and evaluate the performance of MoS2-based electrochemical biosensor by electrochemical impedance spectroscopy (EIS) and differential pulse voltammetry (DPV), respectively. Such MoS2-based biosensor exhibited excellent performance for miRNA-21 detection in the range from 10 fM to 1 nM with detection limit of 0.78 fM and 0.45 fM for DPV and EIS technique, respectively. Furthermore, the proposed MoS2-based biosensor displayed high selectivity and stability, which could be used to determine miRNA-21 in human serum samples with satisfactory results. All data suggested that such MoS2-based nanocomposite may be a potential candidate for biosensing ranging from nucleic acid to protein detection.
Co-reporter:Wen Jing Yang;Tingting Zhao;Peng Zhou;Simou Chen;Yu Gao;Lijun Liang;Xiaodong Wang
Polymer Chemistry (2010-Present) 2017 vol. 8(Issue 20) pp:3056-3065
Publication Date(Web):2017/05/23
DOI:10.1039/C7PY00161D
Surface decoration of nano-carriers is of great importance in targeted drug delivery systems. However, the surface coupling of functional ligands to nano-carriers usually involves sophisticated conjugation chemistry, such as carbodiimide-mediated amide coupling. Herein, “clickable” nanocapsules, containing reactive alkyne groups, were developed for surface functionalization via highly efficient thiol–yne click chemistry and further applied as intelligent drug nano-carriers. Firstly, by employing the facile reflux-precipitation polymerization, the “clickable” nanocapsules with dual thermal and redox responsive properties were readily prepared for further surface functionalization. The “clickable” nanocapsules were subsequently decorated with various functional ligands, including cysteine-folic acid, cysteine-RGD peptide and thiol-functionalized fluorescein isothiocyanate (SH-FITC). Finally, the folate acid-modified nanocapsules (FA-Nanocapsules) were explored as effective drug nano-carriers for doxorubicin (DOX) with triggered release behaviours due to the disulfide linkages and thermo-responsive poly(NIPAAm) components in the nanocapsules. The good growth inhibition of HeLa cells by DOX loaded FA-Nanocapsules indicated that the nanocapsules can be employed as promising drug delivery nano-carriers. The as-prepared dual stimuli-responsive nanocapsules, containing reactive alkyne groups, thus provide a versatile “clickable” platform for surface decoration and functionalization via highly efficient click chemistry.
Co-reporter:Biqing Bao;Jin Zhu;Lina Gong;Jia Chen;Yanrui Pan
RSC Advances (2011-Present) 2017 vol. 7(Issue 6) pp:3528-3533
Publication Date(Web):2017/01/04
DOI:10.1039/C6RA25882D
In this paper, a novel homogeneous hybridization chain reaction (HCR) assay is developed by using cationic conjugated polyelectrolytes (CPEs) as an indicator for the detection of DNA. In this assay, two hairpin probes H1 and H2 are labeled with fluorescein at their 5′-end and 3′-end respectively. After the HCR, the two hairpin probes are triggered by target DNA to form a long two-stranded DNA polymer with numerous fluorescein labelling in the strand, which is resistant to the S1 nuclease degradation. When the CPEs are added, strong electrostatic interaction between fluorescein-labeled DNA and CPEs occurred, which allowed fluorescence resonance energy transfer (FRET) from the CPEs to the fluorescein-labeled DNA and an obvious fluorescence colour change of the conjugated polymer solution. With HCR amplification and CPEs to amplify the fluorescence signal, homogeneous HCR for sensitive DNA detection is performed successfully. This proposed cascade amplification strategy can not only extend the application of HCR but also provides an alternative platform for homogeneous detection of DNA.
Co-reporter:Tingting Li;Dongliang Yang;Liuqing Zhai;Suiliang Wang;Baomin Zhao;Nina Fu;Youtian Tao;Wei Huang
Advanced Science 2017 Volume 4(Issue 4) pp:
Publication Date(Web):2017/04/01
DOI:10.1002/advs.201600166
The fluorophores with long-lived fluorescent emission are highly desirable for time-resolved fluorescence imaging (TRFI) in monitoring target fluorescence. By embedding the aggregates of a thermally activated delayed fluorescence (TADF) dye, 2,3,5,6-tetracarbazole-4-cyano-pyridine (CPy), in distearoyl-sn-glycero-3-phosphoethanolamine-poly(ethylene glycol) (DSPE-PEG2000) matrix, CPy-based organic dots (CPy-Odots) with a long fluorescence lifetime of 9.3 μs (in water at ambient condition) and high brightness (with an absolute fluorescence quantum efficiency of 38.3%) are fabricated. CPy-Odots are employed in time-resolved and confocal fluorescence imaging in living Hela cells and in vivo. The green emission from the CPy-Odots is readily differentiated from the cellular autofluorescence background because of their stronger emission intensities and longer lifetimes. Unlike other widely studied DSPE-PEG2000 encapsulated Odots which are always distributed in cytoplasm, CPy-Odots are located mainly in plasma membrane. In addition, the application of CPy-Odots as a bright microangiography agent for TRFI in zebrafish is also demonstrated. Much broader application of CPy-Odots is also prospected after further surface functionalization. Given its simplicity, high fluorescence intensity, and wide availability of TADF materials, the method can be extended to develop more excellent TADF Odots for accomplishing the challenges in future bioimaging applications.
Co-reporter:Nargish Parvin;Quan Jin;Yanze Wei;Ranbo Yu;Bing Zheng;Ling Huang;Ying Zhang;Hua Zhang;Mingyuan Gao;Huijun Zhao;Wenping Hu;Yuliang Li;Dan Wang
Advanced Materials 2017 Volume 29(Issue 18) pp:
Publication Date(Web):2017/05/01
DOI:10.1002/adma.201606755
Despite recent progress in 2D nanomaterials-based biosensing, it remains challenging to achieve sensitive and high selective detection. This study develops few-layer graphdiyne (GD) nanosheets (NSs) that are used as novel sensing platforms for a variety of fluorophores real-time detection of DNA with low background and high signal-to-noise ratio, which show a distinguished fluorescence quenching ability and different affinities toward single-stranded DNA and double-stranded DNA. Importantly, for the first time, a few-layer GD NSs-based multiplexed DNA sensor is developed.
Co-reporter:Lizhen Chen, Jie Chao, Xiangmeng Qu, Hongbo Zhang, Dan Zhu, Shao Su, Ali Aldalbahi, Lianhui Wang, and Hao Pei
ACS Applied Materials & Interfaces 2017 Volume 9(Issue 9) pp:
Publication Date(Web):February 21, 2017
DOI:10.1021/acsami.6b16764
Adenosine triphosphate (ATP) is a central metabolite that is of critical importance in many cellular processes. The development of sensitive and selective methods for the detection of ATP level in vivo is crucial in diagnostic and theranostic applications. In this work, we have developed a polyA-based aptamer nanobeacon (PAaptNB) with improved efficiency and speed of ATP analysis. We found that the dissociation constants and competitive binding kinetics of the PAaptNB could be programmably regulated by adjusting the polyA length. When the polyA length reached to 30 bases, a 10 μM detection limit for ATP assay with PAaptNB can be achieved (∼10-fold improvement compared with the conventional thiol-based aptamer nanobeacon). The feasibility of the PAaptNB for in vivo assay was further demonstrated by imaging intracellular ATP molecules. This study provides a new strategy to construct high-efficiency and high-speed biosensors for cellular molecules analysis, which holds great potential in bioanalysis and theranostic applications.Keywords: aptamer; cellular analysis; nanobeacon; self-assembly; spherical nucleic acid; surface engineering;
Co-reporter:Chunyuan Song, Boyue Yang, Yu Zhu, Yanjun Yang, Lianhui Wang
Biosensors and Bioelectronics 2017 Volume 87() pp:59-65
Publication Date(Web):15 January 2017
DOI:10.1016/j.bios.2016.07.097
•An excellent SERS sensor for Hg2+ is prepared on a Ag NRs array SERS substrate.•The LOD of the SERS sensor for Hg2+ is low to 0.16 pM.•The SERS sensor owns a specific and linear response to Hg2+ from 1 pM to 1 μM.•The SERS sensor is able to sensitively detect trace Hg2+ in tap water and lake water.With years of outrageous mercury emissions, there is an urgent need to develop convenient and sensitive methods for detecting mercury ions in response to increasingly serious mercury pollution in water. In the present work, a portable, ultrasensitive SERS sensor is proposed and utilized for detecting trace mercury ions in water. The SERS sensor is prepared on an excellent sliver nanorods array SERS substrate by immobilizing T-component oligonucleotide probes labeled with dye on the 3′-end and –SH on the 5′-end. The SERS sensor responses to the specific chemical bonding between thymine and mercury ions, which causes the previous flexible single strand of oligonucleotide probe changing into rigid and upright double chain structure. Such change in the structure drives the dyes far away from the excellent SERS substrate and results in a SERS signal attenuation of the dye. Therefore, by monitoring the decay of SERS signal of the dye, mercury ions in water can be detected qualitatively and quantitatively. The experimental results indicate that the proposed optimal SERS sensor owns a linear response with wide detecting range from 1 pM to 1 μM, and a detection limit of 0.16 pM is obtained. In addition, the SERS sensor demonstrates good specificity for Hg2+, which can accurately identify trace mercury ions from a mixture of ten kinds of other ions. The SERS sensor has been further executed to analyze the trace mercury ions in tap water and lake water respectively, and good recovery rates are obtained for sensing both kinds of water. With its high selectivity and good portability, the ultrasensitive SERS sensor is expected to be a promising candidate for discriminating mercury ions in the fields of environmental monitoring and food safety.
Co-reporter:Zhimin Luo;Guangqin Qi;Keyu Chen;Min Zou;Lihui Yuwen;Xinwen Zhang;Wei Huang
Advanced Functional Materials 2016 Volume 26( Issue 16) pp:2739-2744
Publication Date(Web):
DOI:10.1002/adfm.201505044
Graphene quantum dots (GQDs) with white fluorescence are synthesized by a microwave-assisted hydrothermal method using graphite as the precursor. A solution-processed white-light-emitting diode (WLED) is fabricated using the as-prepared white fluorescent GQDs (white-light-emitting graphene quantum dots, WGQDs) doped 4,4-bis(carbazol-9-yl)biphenyl as the emissive layer. White-light emission is obtained from the WLED with 10 wt% doping concentration of WGQDs, which shows a luminance of 200 cd m−2 at the applied voltage of 11–14 V. Importantly, an external quantum efficiency of 0.2% is achieved, which is the highest among all the reported WLED based on GQDs or carbon dots. The results demonstrate that WGQDs as a novel phosphor may open up a new avenue to develop the environmentally friendly WLEDs for practical application in solid-state lighting.
Co-reporter:Degao Wang, Guoliang Chang, Yuying Zhang, Jie Chao, Jianzhong Yang, Shao Su, Lihua Wang, Chunhai Fan and Lianhui Wang
Nanoscale 2016 vol. 8(Issue 25) pp:12697-12701
Publication Date(Web):01 Jun 2016
DOI:10.1039/C6NR03855G
Herein, we presented hierarchical three-dimensional (3D) branched hematite nanorod arrays (NAs) on transparent fluorine-doped tin oxide (FTO) conductive glass substrates, which exhibited high PEC water splitting performance due to the enhancement of mid-visible light harvesting as well as charge separation and transfer. The introduction of a TiO2 underlayer made the as-prepared 3D branched hematite NAs achieve a photocurrent density of 0.61 mA cm−2 at 1.23 V vs. reversible hydrogen electrode (RHE) without high-temperature activation.
Co-reporter:Lihui Yuwen, Jiajia Zhou, Yuqian Zhang, Qi Zhang, Jingyang Shan, Zhimin Luo, Lixing Weng, Zhaogang Teng and Lianhui Wang
Nanoscale 2016 vol. 8(Issue 5) pp:2720-2726
Publication Date(Web):22 Dec 2015
DOI:10.1039/C5NR08166A
Photothermal therapy (PTT) is a promising cancer treatment with both high effectiveness and fewer side effects. However, an ideal PTT agent not only needs strong absorption of near-infrared (NIR) light and high photothermal conversion efficiency, but also needs good biocompatibility, stability, and small size, which makes the design and preparation of a novel PTT agent a great challenge. In this work, we developed an ultrasonication-assisted liquid exfoliation method for the direct preparation of ultrasmall (2–3 nm) MoSe2 nanodots (NDs) in aqueous solution and demonstrated their superior properties as a PTT agent. The as-prepared MoSe2 NDs have strong absorption of NIR light and high photothermal conversion efficiency of about 46.5%. In vitro cellular experiments demonstrate that MoSe2 NDs have negligible cytotoxicity and can efficiently kill HeLa cells (human cervical cell line) under NIR laser (785 nm) irradiation.
Co-reporter:Chunyuan Song, Yanjun Yang, Boyue Yang, Linghua Min and Lianhui Wang
Journal of Materials Chemistry A 2016 vol. 4(Issue 10) pp:1811-1817
Publication Date(Web):02 Feb 2016
DOI:10.1039/C5TB02780B
The development of an ultrasensitive analysis technique for the combination assay of cancer associated markers is an effective method for the early detection of tumor. Herein, we report a highly sensitive and specific SERS-based sandwich immunoassay for the simultaneous detection of two protein markers associated with lung cancer, including carcinoembryonic antigen (CEA) and neuron-specific enolase (NSE). Two bright SERS tags are prepared by surface modifications of flower-like gold nanoparticles with Raman molecules and target-specific antibodies, and SERS-active magnetic nanoparticles labelled with mixed antibodies are used as immune substrates for capturing the targets and further separating the sandwich structured immune complexes from the mixture. Immunoassays for joint detection of CEA and NSE using both buffer and human serum specimens are performed and the assay results indicate that the proposed SERS-based combination assay of the two markers shows good specificity and ultrahigh sensitivity. The limit of detections of CEA and NSE in human serum specimens are 1.48 pg mL−1 and 2.04 pg mL−1, respectively. The proposed SERS immunoassay is expected to be used for multiple-marker assays of any other tumors and to provide a reliable method for the early screening of cancers in clinic.
Co-reporter:Jie Chao, Wenfang Cao, Shao Su, Lixing Weng, Shiping Song, Chunhai Fan and Lianhui Wang
Journal of Materials Chemistry A 2016 vol. 4(Issue 10) pp:1757-1769
Publication Date(Web):13 Jan 2016
DOI:10.1039/C5TB02135A
Detection of nucleic acid and protein targets related to human health and safety has attracted widespread attention. Surface-enhanced Raman scattering (SERS) is a powerful tool for biomarker detection because of its ultrahigh detection sensitivity and unique fingerprinting spectra. In this review, we first introduce the development of nanostructure-based SERS-active substrates and SERS nanotags, which greatly influence the performance of SERS biosensors. We then focus on recent advances in SERS biosensors for DNA, microRNA and protein determination, including label-free, labeled and multiplex analyses as well as in vivo imaging. Finally, the prospects and challenges of such nanostructure-based SERS biosensors are discussed.
Co-reporter:Lihui Yuwen, Huan Yu, Xiangrong Yang, Jiajia Zhou, Qi Zhang, Yuqian Zhang, Zhimin Luo, Shao Su and Lianhui Wang
Chemical Communications 2016 vol. 52(Issue 3) pp:529-532
Publication Date(Web):29 Oct 2015
DOI:10.1039/C5CC07301D
In this report, we have developed a rapid and versatile ultrasonication enhanced lithium intercalation (ULI) method to prepare single-layer transition metal dichalcogenide nanosheets (TMDC NSs, including MoS2, WS2, and TiS2) by using n-butyllithium (n-BuLi).
Co-reporter:Shao Su, Haofan Sun, Wenfang Cao, Jie Chao, Hongzhen Peng, Xiaolei Zuo, Lihui Yuwen, Chunhai Fan, and Lianhui Wang
ACS Applied Materials & Interfaces 2016 Volume 8(Issue 11) pp:6826
Publication Date(Web):March 3, 2016
DOI:10.1021/acsami.5b12833
A MoS2-based electrochemical aptasensor has been developed for the simultaneous detection of thrombin and adenosine triphosphate (ATP) based on gold nanoparticles-decorated MoS2 (AuNPs–MoS2) nanocomposites. Two different aptamer probes labeled with redox tags were simultaneously immobilized on an AuNPs–MoS2 film modified electrode via Au–S bonds. The aptamers presented structural switches with the addition of target molecules (thrombin and ATP), resulting in methylene blue (MB) far from or ferrocene (Fc) close to the electrode surface. Therefore, a dual signaling detection strategy was developed, which featured both “signal-on” and “signal-off” elements in the detection system because of the target-induced structure switching. This proposed aptasensor could simultaneously determine ATP and thrombin as low as 0.74 nM ATP and 0.0012 nM thrombin with high selectivity, respectively. In addition, thrombin and ATP could act as inputs to activate an AND logic gate.Keywords: aptasensor; gold nanoparticles; logic gates; molybdenum disulfide; simultaneous detection
Co-reporter:Shao Su, Wenfang Cao, Chi Zhang, Xiaoyan Han, Huan Yu, Dan Zhu, Jie Chao, Chunhai Fan and Lianhui Wang
RSC Advances 2016 vol. 6(Issue 80) pp:76614-76620
Publication Date(Web):08 Aug 2016
DOI:10.1039/C6RA12401A
Recently, the use of a molybdenum disulfide (MoS2) nanosheet as a sensing platform has attracted more and more scientists' attention due to its graphene-like structure and excellent physical/chemical properties. Herein, the performances of MoS2-based electrochemical sensors were improved by decorating noble metallic nanoparticles on the surface of the MoS2 nanosheet. Taking catechol (CC) as an analyte, it could be found that the MoS2 nanosheet and its derivatives have excellent electrocatalytic abilities toward CC. More interestingly, the gold nanoparticles-decorated MoS2 nanosheet (Au–MoS2), platinum nanoparticles-decorated MoS2 nanosheet (Pt–MoS2) and gold–platinum core–shell nanoparticles-decorated MoS2 nanosheet (Au@Pt–MoS2) modified electrodes exhibited better detection performances than the pure MoS2 nanosheet and metallic nanoparticles modified electrodes due to their synergistic effect. As expected, the Au@Pt–MoS2 nanocomposites modified electrode exhibited the linear range of 2–1000 μM and the detection limit of 0.44 μM for CC detection, which was better than all MoS2-based nanomaterials. All the MoS2-based electrochemical sensing platforms were employed to determine CC both in buffer and in real samples with satisfactory results, suggesting MoS2-based nanomaterials maybe the potential candidates for constructing electrochemical sensors for chemical and biological molecules detection.
Co-reporter:Yu Gao, Chenjie Xu and Lianhui Wang
RSC Advances 2016 vol. 6(Issue 66) pp:61771-61776
Publication Date(Web):23 Jun 2016
DOI:10.1039/C6RA11636A
Scaffold-based bone tissue engineering often involves the use of human mesenchymal stem cells (hMSCs) that are seeded into three-dimensional (3D) scaffolds and induced to generate new bone by osteoinductive cues. In order to obtain an efficacious reconstruction of bone tissue, hMSCs must grow and differentiate in osteogenic conditions on biomaterial scaffolds to be subsequently implanted in vivo. Traditional evaluation of the osteogenic differentiation of hMSCs on scaffolds depends on time-consuming and cell-destroying end-point assays. This work explores the use of Raman spectroscopy as a non-invasive and real-time imaging method for continuous monitoring of the osteogenic differentiation of hMSCs on a polycaprolactone scaffold. In a period of 28 days, Raman spectroscopic imaging with a single cell resolution provided fingerprint chemical information and structural information on the differentiating hMSCs. Delayed mineralization was observed for hMSC osteogenic differentiation on PCL scaffolds in comparison to that on tissue culture plates.
Co-reporter:Wei Chen, Weiwei Mao, Baoan Bian, Ning Xu, Runfeng Chen, Xing-ao Li, Lianhui Wang
Computational and Theoretical Chemistry 2016 Volume 1091() pp:85-91
Publication Date(Web):1 September 2016
DOI:10.1016/j.comptc.2016.07.015
•The molecular device has been investigated by the first-principles method.•The molecular device exhibits high-performance multi-functional properties.•The results provide new insights into the designing ZGNR-based devices.Based on the first-principles method, the spin-dependent transport properties of covalent-organic molecular device embedded between two zigzag-edge graphene nanoribbon (ZGNR) electrodes have been studied. It is revealed that in the parallel (P) spin configuration of two ZGNR electrodes, the molecular device exhibits a robust spin filtering effect (up to 100%). In another case of antiparallel (AP) spin configuration, dual spin filtering, spin rectifying as well as negative differential resistance (NDR) effects were discovered. These calculated results offer useful ideas for designing high-performance ZGNR-based molecular devices.
Co-reporter:Chunyuan Song;Boyue Yang;Yanjun Yang
Science China Chemistry 2016 Volume 59( Issue 1) pp:16-29
Publication Date(Web):2016 January
DOI:10.1007/s11426-015-5504-9
Mercury ion (Hg2+), known as one of the highly toxic and soluble heavy metal ions, is causing serious environmental pollution and irreversible damage to the health. It is urgent to develop some rapid and ultrasensitive methods for detecting trace mercury ions in the environment especially drink water. Surface-enhanced Raman scattering (SERS) is considered as a novel and powerful optical analysis technique since it has the significant advantages of ultra-sensitivity and high specificity. In recent years, the SERS technique and its application in the detection of Hg2+ have become more prevalent and compelling. This review provides an overall survey of the development of SERS-based Hg2+ detections and presents a summary relating to the basic principles, detection strategies, recent advances and current challenges of SERS for Hg2+ detections.
Co-reporter:Dongliang Yang;Fei Li;Zhimin Luo;Biqing Bao;Yanling Hu;Lixing Weng;Yixiang Cheng
Journal of Polymer Science Part A: Polymer Chemistry 2016 Volume 54( Issue 12) pp:1686-1693
Publication Date(Web):
DOI:10.1002/pola.28024
ABSTRACT
In this article, a novel zwitterionic conjugated polyelectrolyte containing tetraphenylethene unit was synthesized via Pd-catalyzed Sonogashira reaction. The resulting polymer (P2), which exhibited typical aggregation-induced emission (AIE) properties, was weakly fluorescent in dilute DMSO solution and showed bright fluorescence emissions when aggregated in DMSO/water mixtures or fabricated into conjugated polymer nanoparticles (CPNs). The nanoparticles from P2 could be prepared by reprecipitation method with an average diameter around 23 nm. Notably, the cell-staining efficiencies of lipid-P2 nanoparticles could be enhanced with lipid encapsulation and these nanoparticles were endocytosed via caveolae-mediated and clathrin-mediated endocytosis pathways. Furthermore, the lipid-P2 nanoparticles with low cytotoxicity, high photostability and efficient cell staining ability could be employed for in vitro detection of Fe3+ ions in A549 cells. © 2016 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2016, 54, 1686–1693
Co-reporter:Ying Zhang;Bing Zheng;Changfeng Zhu;Xiao Zhang;Chaoliang Tan;Hai Li;Bo Chen;Jian Yang;Junze Chen;Ying Huang;Hua Zhang
Advanced Materials 2015 Volume 27( Issue 5) pp:935-939
Publication Date(Web):
DOI:10.1002/adma.201404568
Co-reporter:Jing Tian; Xiao Zeng; Xiaoji Xie; Sanyang Han; Oi-Wah Liew; Yei-Tsung Chen; Lianhui Wang;Xiaogang Liu
Journal of the American Chemical Society 2015 Volume 137(Issue 20) pp:6550-6558
Publication Date(Web):April 29, 2015
DOI:10.1021/jacs.5b00981
Growing interest in lanthanide-doped nanoparticles for biological and medical uses has brought particular attention to their safety concerns. However, the intrinsic toxicity of this new class of optical nanomaterials in biological systems has not been fully evaluated. In this work, we systematically evaluate the long-term cytotoxicity of lanthanide-doped nanoparticles (NaGdF4 and NaYF4) to HeLa cells by monitoring cell viability (mitochondrial activity), adenosine triphosphate (ATP) level, and cell membrane integrity (lactate dehydrogenase release), respectively. Importantly, we find that ligand-free lanthanide-doped nanoparticles induce intracellular ATP deprivation of HeLa cells, resulting in a significant decrease in cell viability after exposure for 7 days. We attribute the particle-induced cell death to two distinct cell death pathways, autophagy and apoptosis, which are primarily mediated via the interaction between the nanoparticle and the phosphate group of cellular ATP. The understanding gained from the investigation of cytotoxicity associated with lanthanide-doped nanoparticles provides keen insights into the safe use of these nanoparticles in biological systems.
Co-reporter:Chaoliang Tan; Peng Yu; Yanling Hu; Junze Chen; Ying Huang; Yongqing Cai; Zhimin Luo; Bing Li; Qipeng Lu; Lianhui Wang; Zheng Liu;Hua Zhang
Journal of the American Chemical Society 2015 Volume 137(Issue 32) pp:10430-10436
Publication Date(Web):August 4, 2015
DOI:10.1021/jacs.5b06982
High-yield preparation of ultrathin two-dimensional (2D) nanosheets is of great importance for the further exploration of their unique properties and promising applications. Herein, for the first time, the high-yield and scalable production of ultrathin 2D ternary chalcogenide nanosheets, including Ta2NiS5 and Ta2NiSe5, in solution is achieved by exfoliating their layered microflakes. The size of resulting Ta2NiS5 and Ta2NiS5 nanosheets ranges from tens of nanometers to few micrometers. Importantly, the production yield of single-layer Ta2NiS5 nanosheets is very high, ca. 86%. As a proof-of-concept application, the single-layer Ta2NiS5 is used as a novel fluorescence sensing platform for the detection of DNA with excellent selectivity and high sensitivity (with detection limit of 50 pM). These solution-processable, high-yield, large-amount ternary chalcogenide nanosheets may also have potential applications in electrocatalysis, supercapacitors, and electronic devices.
Co-reporter:Shao Su, Min Zou, He Zhao, Chengfeng Yuan, Yanan Xu, Chi Zhang, Lihua Wang, Chunhai Fan and Lianhui Wang
Nanoscale 2015 vol. 7(Issue 45) pp:19129-19135
Publication Date(Web):20 Oct 2015
DOI:10.1039/C5NR05614D
Herein, a facile approach for shape-controlled gold nanoparticle (AuNP) decorated thionine–MoS2 nanocomposites (AuNP–Thi–MoS2) had been reported by using the synergistic effect of MoS2 and Thi. Thi was not only used as an electrochemical indicator, but also as a reducing agent to tune the resulting morphologies of AuNPs. With the ratio of MoS2/Thi decreasing, the shapes of AuNPs changed from spherical, triangle, clover-like to flower-like nanostructures. TEM, XRD and XPS were employed to characterize the formation and chemical composition of AuNP–Thi–MoS2 nanocomposites. On the basis of synthesis, a MoS2-based label-free electrochemical immunosensor had been designed to detect carcino-embryonic antigen (CEA). The proposed immunosensor could detect as low as 0.52 pg mL−1 CEA with excellent selectivity. Moreover, the expected immunosensor showed high stability and excellent reproducibility, which could detect CEA in human serum with satisfactory results. Therefore, the AuNP–Thi–MoS2 nanocomposites may be considered as a candidate sensing platform for fabrication of simple, label-free and ultrasensitive electrochemical sensors.
Co-reporter:C. Y. Song, N. Zhou, B. Y. Yang, Y. J. Yang and L. H. Wang
Nanoscale 2015 vol. 7(Issue 40) pp:17004-17011
Publication Date(Web):16 Sep 2015
DOI:10.1039/C5NR04827C
The physicochemical properties of noble metal nanocrystals depend strongly on their size and shape, and it is becoming clear that the design and facile synthesis of particular nanostructures with tailored shape and size is especially important. Herein a novel class of hydrangea flower-like hierarchical gold nanostructures with tunable surface topographies and optical properties are prepared for the first time by a facile, one-pot, seedless synthesis using ascorbic acid (AA) to reduce hydrogen tetrachloroaurate (HAuCl4) in the presence of (1-hexadecyl)trimethylammonium chloride (CTAC). The morphologies of the synthesized gold nanoflowers are controlled and fine-tuned by varying the synthetic conditions such as the concentration of reagents and the growth temperature. Due to their unique hierarchical three-dimensional (3D) structures with rich hot spots, these gold nanoflowers exhibit an efficient performance in single-particle surface-enhanced Raman scattering (SERS). The work stands out as an interesting approach for anisotropic particle synthesis and morphological control, and the proposed novel, hierarchical gold nanoflowers have a number of exciting potential applications in SERS-based sensors.
Co-reporter:Chunhui Dai, Dongliang Yang, Wenjie Zhang, Xiao Fu, Qingmin Chen, Chengjian Zhu, Yixiang Cheng and Lianhui Wang
Journal of Materials Chemistry A 2015 vol. 3(Issue 35) pp:7030-7036
Publication Date(Web):21 Jul 2015
DOI:10.1039/C5TB01262G
Three new boron ketoiminate-based conjugated polymers P1, P2, and P3 were designed and synthesized through the Sonogashira coupling reaction of 4,6-bis(4-bromophenyl)-2,2-difluoro-3-phenyl-2H-1,3,2-oxazaborinin-3-ium-2-uide (M1) with 1,4-diethynyl-2,5-bis(octyloxy)benzene (M2), 3,6-diethynyl-9-octyl-9H-carbazole (M3) and 3,7-diethynyl-10-octyl-10H-phenothiazine-S,S-dioxide (M4), respectively. All the resulting polymers showed obvious aggregation-induced emission (AIE) behaviours. Interestingly, it was found that a great difference in the electron-donating abilities of the D–A type polymer linkers can lead to the unique AIE behaviour of the alternating polymers in the aggregate state, which provides us with a practical strategy to design tunable AIE-active conjugated polymers. Most importantly, studies on MCF-7 breast cancer cell imaging revealed that the nanoparticles fabricated from the conjugated polymers could serve as promising fluorescent probes with low cytotoxicity and high photostability.
Co-reporter:Yanling Hu, Lei Zhang, Ying Zhang, Bin Wang, Yawei Wang, Quli Fan, Wei Huang, and Lianhui Wang
ACS Applied Materials & Interfaces 2015 Volume 7(Issue 4) pp:2459
Publication Date(Web):December 29, 2014
DOI:10.1021/am507218g
MicroRNAs (miRNAs), a class of small, endogenous, noncoding RNA molecules, can serve as biomarkers for potential applications in cancer diagnosis, prognosis, and prediction due to its abnormal expression. As a result, a novel label-free biosensor with nanometer scale was prepared and employed in the detection of trace oligonucleotides based on the localized surface plasmon resonance (LSPR). The dielectric constant on the surface of DNA modified gold nanoparticle would change when probe single-strand DNA hybridized with target oligonucleotides, which resulted in the notable red shift of scattering peak position. The biosensor with excellent selectivity can be used in a real-time monitoring hybridization process. Notably, this method provided label-free detection of DNA and miRNA at single nanoparticle level with limit of detection up to 3 nM. Due to the advantages of LSPR scattering spectra, single nanoparticle biosensor can be designed for trace cancer-relevant miRNAs detection in the future.Keywords: biosensor; oligonucleotide detection; single gold nanoparticle; surface plasmon resonance
Co-reporter:Cui-e Zhao, Jia Chen, Yuanzhao Ding, Victor Bochuan Wang, Biqing Bao, Staffan Kjelleberg, Bin Cao, Say Chye Joachim Loo, Lianhui Wang, Wei Huang, and Qichun Zhang
ACS Applied Materials & Interfaces 2015 Volume 7(Issue 26) pp:14501
Publication Date(Web):June 16, 2015
DOI:10.1021/acsami.5b03990
Water-soluble conjugated oligoelectrolyte nanoparticles (COE NPs), consisting of a cage-like polyhedral oligomeric silsesquioxanes (POSS) core equipped at each end with pendant groups (oligo(p-phenylenevinylene) electrolyte, OPVE), have been designed and demonstrated as an efficient strategy in increasing the current generation in Escherichia coli microbial fuel cells (MFCs). The as-prepared COE NPs take advantage of the structure of POSS and the optical properties of the pendant groups, OPVE. Confocal laser scanning microscopy showed strong photoluminescence of the stained cells, indicating spontaneous accumulation of COE NPs within cell membranes. Moreover, the electrochemical performance of the COE NPs is superior to that of an established membrane intercommunicating COE, DSSN+ in increasing current generation, suggesting that these COE NPs thus hold great potential to boost the performance of MFCs.Keywords: conjugated oligoelectrolyte (COE); current generation; microbial fuel cells; nanoparticles; polyhedral oligomeric silsesquioxanes (POSS);
Co-reporter:Zhimin Luo, Dongliang Yang, Guangqin Qi, Lihui Yuwen, Yuqian Zhang, Lixing Weng, Lianhui Wang, and Wei Huang
ACS Applied Materials & Interfaces 2015 Volume 7(Issue 16) pp:8539
Publication Date(Web):April 20, 2015
DOI:10.1021/acsami.5b00297
Water-dispersed reduced graphene oxide/chitosan oligosaccharide (RGO-CTSO) was prepared by chemical reduction of graphene oxide and synchronous functionalization with biocompatible chitosan oligosaccharide (CTSO). ζ potential measurement indicated that RGO-CTSO was highly stable in the acidic aqueous solution. RGO-CTSO was used to modify glassy carbon electrode (GCE) as the growth template of Escherichia coli (E. coli). The enhanced direct electron transfer of E. coli on the RGO-CTSO-modified GCE was studied by cyclic voltammetry. Compared with GCE or RGO-modified GCE, RGO-CTSO-modified GCE was more suitable for the adhesion growth of E. coli to improve direct electron transfer. The biocompatibility and versatility of RGO-CTSO made it promising for use as an anode material in microbial fuel cells.Keywords: chitosan oligosaccharide; direct electron transfer; Escherichia coli; reduced graphene oxide;
Co-reporter:Lei Zhang, Ying Zhang, Yanling Hu, Quli Fan, Wenjing Yang, Anran Li, Shuzhou Li, Wei Huang and Lianhui Wang
Chemical Communications 2015 vol. 51(Issue 2) pp:294-297
Publication Date(Web):16 Oct 2014
DOI:10.1039/C4CC06663D
We developed a novel method for the real-time monitoring of the delicate change in refractive index (RI) when DNA or RNA hybridize near a DNA-capped silver nanocube (AgNC) surface. This method offers an alternative platform in the quantitative analysis of the trace lung cancer-associated miRNAs in label-free detection.
Co-reporter:Biqing Bao;Mingfeng Ma;Huafeng Zai;Lei Zhang;Nina Fu;Wei Huang
Advanced Science 2015 Volume 2( Issue 3) pp:
Publication Date(Web):
DOI:10.1002/advs.201400009
Hybridbio/-synthetic sensory conjugated polymer nanoparticles (CPNs) are developed for selective label-free detection of target ssDNA in serum. Carboxylic acid-functionalized anionic polyfluorene nanoparticles are rationally designed as signal amplifying unit to bioconjugate with amine functionalized single stranded oligonucleotides as a receptor. The covalent DNA coating can significantly improve the photostability of the DNA-bioconjugated CPNs over a wide range of buffer conditions. Better ssDNA discrimination for the DNA-bioconjugated CPNs sensor is achieved owing to increased interchain interactions and more efficient exciton transport in nanoparticles. The distinguishable fluorescent color for DNA-bioconjugated CPNs in the presence of target ssDNA allows naked-eye detection of ssDNA under UV irradiation.
Co-reporter:Wen Jing Yang, Xi Tao, Tingting Zhao, Lixing Weng, En-Tang Kang and Lianhui Wang
Polymer Chemistry 2015 vol. 6(Issue 39) pp:7027-7035
Publication Date(Web):17 Aug 2015
DOI:10.1039/C5PY00936G
Multifunctional self-healing hydrogel coatings based on a dynamic disulfide exchange reaction were developed via surface-initiated thiol–ene photopolymerization. The functional monomers (poly(ethylene glycol)methyl ether methacrylate (PEGMA), N-hydroxyethyl acrylamide (HEAA) and 2-(methacryloyloxy)ethyl trimethylammonium chloride (META)) and a disulfide-containing crosslinker bis(2-methacryloyl)oxyethyl disulfide (BMOD) were employed for the preparation of antifouling, antibacterial and self-healing hydrogel coatings. The hydrogel coatings reduced protein adsorption, as well as bacterial adhesion from Gram-negative Escherichia coli (E. coli). Moreover, the coatings exhibited good self-healing ability at moderate temperatures due to the dynamic disulfide exchange reaction. Introduction of self-healing ability provides a promising means for self-repairing of microcracks of functional polymer coatings and improving their stability and durability in the long-term applications as biomaterials.
Co-reporter:Chunhui Dai, Dongliang Yang, Xiao Fu, Qingmin Chen, Chengjian Zhu, Yixiang Cheng and Lianhui Wang
Polymer Chemistry 2015 vol. 6(Issue 28) pp:5070-5076
Publication Date(Web):05 Jun 2015
DOI:10.1039/C5PY00733J
In this study, four boron ketoiminate-based conjugated polymers P1–P4 are designed and synthesized via Suzuki polymerization. The resulting polymers are weakly fluorescent in pure THF solutions, but become highly emissive when aggregated in THF/water mixtures or fabricated into conjugated polymer nanoparticles (CPNs), showing typical AIE (AIEE) behaviors. CPNs from P1–P4 could be prepared by reprecipitation with the particle size ranging from 85 to 95 nm. Interestingly, the tuning of the emission color of P1–P4 nanoparticles (NPs) could be conveniently accomplished by varying the substituent in the phenyl ring, which can be ascribed to the donor–acceptor interaction between the substituted phenyl ring and the boron chelating ring. The DFT theoretical calculation of the polymer repeating units indicates that the band gaps of P1–P4 can be tuned in the range 2.72–3.40 eV, suggesting that substituents in the polymer backbone have a great influence on their electronic structures and thus change AIE (AIEE) properties. Furthermore, all of the four CPNs with low cytotoxicity and high photostability could be further employed for HeLa cell imaging.
Co-reporter:Chunhui Dai, Dongliang Yang, Wenjie Zhang, Biqing Bao, Yixiang Cheng and Lianhui Wang
Polymer Chemistry 2015 vol. 6(Issue 21) pp:3962-3969
Publication Date(Web):13 Apr 2015
DOI:10.1039/C5PY00344J
A novel chiral conjugated polymer is developed and used for the preparation of conjugated polymer nanoparticles (CPNs) with particle sizes ranging from 80 to 190 nm. The size-dependent optical properties of chiral CPNs are fully studied and it was found that the nanoparticles exhibited a prominent red shift both in UV-vis and fluorescence emission with increasing diameters. The circular dichroism (CD) spectra and anisotropy r values of the CPNs display size-tunable chirality features, which can be attributed to the nature of the aggregates as nanoparticles grow. Meanwhile, the obtained CPNs can serve as efficient far-red/near-infrared (FR/NIR) fluorescent probes with low cytotoxicity and high photostability for HeLa cell imaging.
Co-reporter:Wei Chen, Runfeng Chen, Baoan Bian, Xing-ao Li, Lianhui Wang
Computational and Theoretical Chemistry 2015 Volume 1067() pp:114-118
Publication Date(Web):1 September 2015
DOI:10.1016/j.comptc.2015.05.016
•The dihydroazulene molecule may behave as an optical molecular switch.•The current through closed configurations is obviously larger than that of the open one.•The switching ratio remain steady when the bias is lesser than 1.4 V.By using non-equilibrium Green’s function formalism combined with density functional theory, we investigate the electronic transport properties of a dihydroazulene molecule with the open and closed configurations by photo-excitation sandwiched between two Au electrodes. This study demonstrates the current through the closed configuration is significantly higher than that of the open configuration, indicating that the dihydroazulene molecule can be used as molecular optical switch within a stable switching ratio at finite bias. The mechanisms of the molecular switch are in detail analyzed by transmission spectra, spatial distribution of molecular orbitals and molecular projected self-consistent Hamiltonian (MPSH) states.Graphical abstract
Co-reporter:Chunyuan Song, Jing Chen, Yiping Zhao and Lianhui Wang
Journal of Materials Chemistry A 2014 vol. 2(Issue 43) pp:7488-7494
Publication Date(Web):28 Aug 2014
DOI:10.1039/C4TB01207K
In sandwich SERS immunoassays, the SERS-active substrate plays a central role in the detection sensitivity. Silver nanorod (AgNR) arrays fabricated by oblique angle deposition (OAD) provide superior analytical qualities and have been demonstrated as excellent SERS substrates. This work reports highly sensitive sandwich immunoassays performed on the OAD-AgNR substrates for the first time, utilizing 4-MBA-labeled immuno-Au nanoparticles (Im-AuNPs) as SERS tags. The aligned AgNR arrays were first deposited on glass slides by OAD, and the surface modified with gold (Au) using chloroauric acid solution via a galvanic replacement reaction. Immunoassays executed on both AgNR arrays and Au-modified AgNR arrays show higher detection sensitivity compared to that performed on self-assembled silver nanoparticles substrates. Though the AgNRs demonstrate better SERS activity than Au-modified AgNRs, the immunoassay performed on the Au-modified AgNRs exhibits higher sensitivity. Further characterization by scanning electron microscopy and fluorescence spectroscopy shows that the improved sensitivity can be attributed to the increased number of Im-AuNPs that are specifically captured on the Au-modified nanorods surface and their more uniform distribution. Concentration-dependent SERS spectra of human IgG on the Au-modified AgNR arrays reveal a good linear response range from 100 fg mL−1 to 100 ng mL−1, with an LOD of 2.5 fg mL−1.
Co-reporter:Lihui Yuwen, Fei Xu, Bing Xue, Zhimin Luo, Qi Zhang, Biqing Bao, Shao Su, Lixing Weng, Wei Huang and Lianhui Wang
Nanoscale 2014 vol. 6(Issue 11) pp:5762-5769
Publication Date(Web):20 Jan 2014
DOI:10.1039/C3NR06084E
A general and facile method for water-dispersed noble metal (Au, Ag, Pd, Pt) nanocrystal modified MoS2 nanosheets (NM–MoS2 NSs) has been developed. By using sodium carboxymethyl cellulose as a stabilizer, well-dispersed NM–MoS2 NSs with homogeneously deposited noble metal nanocrystals (NM NCs) can be synthesized in aqueous solutions. Due to the transition from the semiconducting 2H phase to the metallic 1T phase, the chemically exfoliated MoS2 (ce-MoS2) NSs have improved electrochemical activity. The partially metallic nature of the ce-MoS2 NSs and the catalytic activity of the NM NCs synergistically make NM–MoS2 NSs a potential electrochemical catalyst. For the first time, Pd–MoS2 NSs were used as an electrocatalyst for methanol oxidation in alkaline media. The results showed that Pd–MoS2 NSs have enhanced catalytic activity with 2.8-fold anodic peak current mass density compared to a commercial Pd/C catalyst, suggesting potential for application in direct methanol fuel cells (DMFCs).
Co-reporter:Zhimin Luo, Dongliang Yang, Guangqin Qi, Jingzhi Shang, Huanping Yang, Yanlong Wang, Lihui Yuwen, Ting Yu, Wei Huang and Lianhui Wang
Journal of Materials Chemistry A 2014 vol. 2(Issue 48) pp:20605-20611
Publication Date(Web):05 Nov 2014
DOI:10.1039/C4TA05096G
A facile solvothermal method assisted by microwave irradiation was developed for preparing nitrogen and sulfur co-doped reduced graphene oxide functionalized with fluorescent graphene quantum dots (N,S-RGO/GQDs). Graphene quantum dots (GQDs) show high fluorescence and excitation-dependent fluorescent properties. The resultant N,S-RGO/GQDs hybrids as a kind of metal-free electrocatalyst were demonstrated to have good catalytic properties with long-term operational stability and tolerance to the crossover effects of methanol for oxygen reduction via a four-electron pathway in alkaline solution. This research not only develops a low-cost, economic and scalable approach for preparing a metal-free electrocatalyst for the oxygen reduction reaction (ORR), but also produces nitrogen and sulfur co-doped graphene quantum dots (N,S-GQDs) with high fluorescent characteristics.
Co-reporter:Biqing Bao, Mingfeng Ma, Jia Chen, Lihui Yuwen, Lixing Weng, Quli Fan, Wei Huang, and Lianhui Wang
ACS Applied Materials & Interfaces 2014 Volume 6(Issue 14) pp:11129
Publication Date(Web):June 25, 2014
DOI:10.1021/am503004z
A facile and efficient strategy to prepare multicolor and surface-functionalizable conjugated polymer nanoparticles (PPVseg-COOH CPNs) was demonstrated. The CPNs with tunable photoluminescence colors and carboxylate groups were further covalently modified with a series of specific molecules such as streptavidin, IgG and poly(ethylene glycol) to show their generality for subsequent bioconjugation and biological applications. The streptavidin coating can significantly improve the photostability of the PPVseg-SA CPNs, which indicates that specific biomolecules such as streptavidin functionalization of multicolor PPVseg-COOH CPNs can be applied to achieve high optical stability of CPNs in various buffer solutions, metal ions for many biological applications. Furthermore, the resulted PPVseg-SA CPNs also show efficient labeling ability in specific cellular imaging. The synthetic methods present the feasibility and versatility for further developing surface-functionalizable CPNs probes with full-color tunability for biological imaging and bioanalytical applications.Keywords: bioconjugate; cellular imaging; conjugated polymer; multicolor; nanoparticles
Co-reporter:Degao Wang, Yuying Zhang, Jianqiang Wang, Cheng Peng, Qing Huang, Shao Su, Lianhui Wang, Wei Huang, and Chunhai Fan
ACS Applied Materials & Interfaces 2014 Volume 6(Issue 1) pp:36
Publication Date(Web):December 16, 2013
DOI:10.1021/am405137p
Hematite is a promising semiconductor candidate for PEC water splitting. However, hematite is far well short of the theoretical value of solar-to-fuel conversion efficiency because of the fast recombination of photogenerated carriers. To address this limitation, a facile template-free preparation of hematite photoanode with nanostructured ATO (antimony-doped tin oxide) conductive underlayer served as a scaffold to transport photogenerated electron was developed to decrease the recombination opportunities of the carriers. Furthermore, the constructed ATO scaffold could also increase the light absorption of hematite and the number of the carriers, resulting in better PEC performance of hematite.Keywords: antimony-doped tin oxide; conductive underlayer; nanostructured hematite photoanode; photoelectrochemical; water splitting;
Co-reporter:Shao Su, Jinwei Fan, Bing Xue, Lihui Yuwen, Xingfen Liu, Dun Pan, Chunhai Fan, and Lianhui Wang
ACS Applied Materials & Interfaces 2014 Volume 6(Issue 2) pp:1152
Publication Date(Web):December 31, 2013
DOI:10.1021/am404811j
Herein, we report a convenient approach to developing quantum dots (QDs)-based nanosensors for DNA and micro-RNA (miRNA) detection. The DNA-QDs conjugate was prepared by a ligand-exchange method. Thiol-labeled ssDNA is directly attached to the QD surface, leading to highly water-dispersible nanoconjugates. The DNA-QDs conjugate has the advantages of the excellent optical properties of QDs and well-controlled recognition properties of DNA and can be used as a nanoprobe to construct a nanosensor for nucleic acid detection. With the addition of a target nucleic acid sequence, the fluorescence intensity of QDs was quenched by an organic quencher (BHQ2) via Förster resonance energy transfer. This nanosensor can detect as low as 1 fM DNA and 10 fM miRNA. Moreover, the QDs-based nanosensor exhibited excellent selectivity. It not only can effectively distinguish single-base-mismatched and random nucleic sequences but also can recognize pre-miRNA and mature miRNA. Therefore, the nanosensor has high application potential for disease diagnosis and biological analysis.Keywords: DNA; FRET; micro-RNA; nanosensor; quantum dots;
Co-reporter:Shao Su, Chi Zhang, Lihui Yuwen, Jie Chao, Xiaolei Zuo, Xingfen Liu, Chunyuan Song, Chunhai Fan, and Lianhui Wang
ACS Applied Materials & Interfaces 2014 Volume 6(Issue 21) pp:18735
Publication Date(Web):October 13, 2014
DOI:10.1021/am5043092
Herein, a reliable surface-enhanced Raman scattering (SERS)-active substrate has been prepared by synthesizing gold nanoparticles (AuNPs)-decorated MoS2 nanocomposite. The AuNPs grew in situ on the surface of MoS2 nanosheet to form efficient SERS hot spots by a spontaneous redox reaction with tetrachloroauric acid (HAuCl4) without any reducing agent. The morphologies of MoS2 and AuNPs-decorated MoS2 nanosheet were characterized by TEM, HRTEM, and AFM. The formation of hot spots greatly depended on the ratio of MoS2 and HAuCl4. When the concentration of HAuCl4 was 2.4 mM, the as-prepared AuNPs@MoS2-3 nanocomposite exhibited a high-quality SERS activity toward probe molecule due to the generated hot spots. The spot-to-spot SERS signals showed that the relative standard deviation (RSD) in the intensity of the main Raman vibration modes (1362, 1511, and 1652 cm–1) of Rhodamine 6G were about 20%, which displayed good uniformity and reproducibility. The AuNPs@MoS2-based substrate was reliable, sensitive, and reproducible, which showed great potential to be an excellent SERS substrate for biological and chemical detection.Keywords: AuNPs@MoS2 nanocomposite; hot spot; SERS-active substrate; uniformity
Co-reporter:Chunyuan Song, Linghua Min, Ni Zhou, Yanjun Yang, Shao Su, Wei Huang, and Lianhui Wang
ACS Applied Materials & Interfaces 2014 Volume 6(Issue 24) pp:21842
Publication Date(Web):August 4, 2014
DOI:10.1021/am502636h
A new class of flowerlike gold mesostructure in high yield is successfully synthesized through a facile one-step route using ascorbic acid as a reducing agent of gold salt with cetyltrimethylammonium chloride (CTAC) as surfactant. The as-prepared Au particles have spherical profiles with an averaged diameter of 770 ± 50 nm, but showing a highly rough surface consisting of many irregular and randomly arranged protrusions. The Au mesoflowers exhibit strong surface-enhanced effects and near-infrared absorption which were utilized in the design of efficient surface-enhanced Raman scattering (SERS) tags as immunosensors for immunoassay with improved sensitivity. The experimental results indicate that a good linear relationship is found between the peak intensity at 1071 cm–1 and the logarithm of H-IgG concentration in the range between 1 ng/mL and 1 fg/mL, and the limit of detection (LOD) is 1 fg/mL.Keywords: flowerlike gold mesostructures; immunoassay; SERS tags; surface-enhanced Raman scattering
Co-reporter:Chunyuan Song, Linghua Min, Ni Zhou, Yanjun Yang, Boyue Yang, Lei Zhang, Shao Su and Lianhui Wang
RSC Advances 2014 vol. 4(Issue 78) pp:41666-41669
Publication Date(Web):28 Aug 2014
DOI:10.1039/C4RA08402K
In this work, an ultrasensitive detection of cancer marker CEA has been developed by using novel gold nanoflowers as SERS tags and SERS-active magnetic nanoparticles as supporting substrates. A good linear relationship between concentration and SERS intensity is found in the range between 0.01 fg mL−1 and 1 ng mL−1, and the LOD is 0.01 fg mL−1.
Co-reporter:Haofan Sun, Jie Chao, Xiaolei Zuo, Shao Su, Xingfen Liu, Lihui Yuwen, Chunhai Fan and Lianhui Wang
RSC Advances 2014 vol. 4(Issue 52) pp:27625-27629
Publication Date(Web):13 Jun 2014
DOI:10.1039/C4RA04046E
An electrochemical sensor has been developed for simultaneous detection of dopamine (DA), uric acid (UA) and ascorbic acid (AA) based on a gold nanoparticle-decorated MoS2 nanocomposite (AuNPs@MoS2) modified electrode. The AuNPs@MoS2 nanocomposite has been synthesized by electrodeposition of AuNPs on the MoS2 nanosheets, which possesses better properties than pure AuNPs and MoS2. The AuNPs@MoS2 film modified electrode showed excellent electrocatalytic activity toward the oxidation of AA, DA and UA with three well-resolved oxidation peaks. The peak separation of AA–DA, DA–UA and AA–UA is 151 mV, 137 mV and 288 mV, respectively, which permits the modified electrode to individually or simultaneously analyze AA, DA and UA by differential pulse voltammetry (DPV). Under optimum conditions, the AuNPs@MoS2 modified electrode exhibits linear response toward AA, DA and UA in the range of 50–100000 μM, 0.05–30 μM and 50–40000 μM, respectively. Moreover, the MoS2-based modified electrode was successfully employed to determine DA in human serum samples with satisfactory results.
Co-reporter:Shao Su;Haofan Sun;Fei Xu;Lihui Yuwen;Chunhai Fan
Microchimica Acta 2014 Volume 181( Issue 13-14) pp:1497-1503
Publication Date(Web):2014 October
DOI:10.1007/s00604-014-1178-9
An electrochemical glucose biosensor was developed by immobilizing glucose oxidase (GOx) on a glass carbon electrode that was modified with molybdenum disulfide (MoS2) nanosheets that were decorated with gold nanoparticles (AuNPs). The electrochemical performance of the modified electrode was investigated by cyclic voltammetry, and it is found that use of the AuNPs-decorated MoS2 nanocomposite accelerates the electron transfer from electrode to the immobilized enzyme. This enables the direct electrochemistry of GOx without any electron mediator. The synergistic effect the MoS2 nanosheets and the AuNPs result in excellent electrocatalytic activity. Glucose can be detected in the concentration range from 10 to 300 μM, and down to levels as low as 2.8 μM. The biosensor also displays good reproducibility and long-term stability, suggesting that it represents a promising tool for biological assays.
Co-reporter:Li-Xing Weng;Yu-Xiang Yang;Yu-Qian Zhang
Applied Microbiology and Biotechnology 2014 Volume 98( Issue 6) pp:2565-2572
Publication Date(Web):2014 March
DOI:10.1007/s00253-013-5420-x
Quorum sensing (QS) has been recognized to play an important role in many pathogenic bacteria and has become a novel target for the treatment of infectious disease. Pseudomonas aeruginosa is highly resistant to antibiotic treatment, largely due to its ability to form biofilms, and QS was found to be essential for the creation of mature, differentiated biofilms in this organism. A novel QS inhibitor, C2 (N-decanoyl-l-homoserine benzyl ester), can attenuate not only total protease and elastase activity, but also swarming motility and biofilm formation in the P. aeruginosa strain PAO1. We demonstrated that C2 showed a significant inhibitory effect on biofilm formation in a dose-dependent manner. Data from cDNA microarray showed that expression of 382 genes (∼6.4 %) was significantly different with C2 treatment, including downregulation of 215 genes (∼3.6 %) and upregulation of 167 genes (∼2.8 %). Real-time reverse transcription-polymerase chain reaction (RT-PCR) showed that the gene qscR, which encodes the LuxR-type receptor QscR (quorum sensing control repressor), was significantly upregulated by 375.4 % during C2 treatment. The mechanism by which C2 inhibits biofilm formation may be through repression of Las and Rhl systems by QscR. C2 was shown to reduce biofilm formation; in combination with antibiotics, it abolishes biofilm formation completely. This result may pave the way for new treatments for biofilm-related infections and may be exploited for the general prevention of biofilm formation.
Co-reporter:Biqing Bao, Nanjiao Tao, Dongliang Yang, Lihui Yuwen, Lixing Weng, Quli Fan, Wei Huang and Lianhui Wang
Chemical Communications 2013 vol. 49(Issue 90) pp:10623-10625
Publication Date(Web):24 Sep 2013
DOI:10.1039/C3CC46605A
The authors demonstrate a smart and versatile approach for preparing multi-spectral conjugated polymers from a commercial precursor MEH–PPV without tedious synthetic modification. Multi-color CPNs with small size have also been successfully prepared using a modified-reprecipitation procedure for live cell imaging.
Co-reporter:Yujie Han, Zhimin Luo, Lihui Yuwen, Jing Tian, Xingrong Zhu, Lianhui Wang
Applied Surface Science 2013 Volume 266() pp:188-193
Publication Date(Web):1 February 2013
DOI:10.1016/j.apsusc.2012.11.132
Abstract
A facile aqueous solution procedure has been developed to synthesize silver nanoparticles (Ag NPs) on reduced graphene oxide (RGO) (RGO/Ag NPs) with starch as an ideal reductant and stabilizer in one pot under microwave irradiation. Graphene oxide and Ag(NH3)2+ were reduced simultaneously by starch in the process of forming Ag NPs. The size of Ag NPs decorated on the RGO sheets is about 20–50 nm and the average size of Ag NPs on RGO is 34 nm calculated by X-ray diffraction. RGO and RGO/Ag NPs prepared with starch show good stability in aqueous solution. With the decoration of Ag NPs on RGO, Raman intensity of RGO increased evidently. Antimicrobial activity of RGO/Ag NPs was investigated against the gram negative bacteria Pseudomonous aeruginosa. The minimum inhibitory concentration (MIC) of RGO/Ag NPs is 0.2 wt%. The antimicrobial activity of RGO/Ag NPs is stronger than Ag NPs because of the synergic effect of RGO and Ag NPs.
Co-reporter:Zhimin Luo, Lihui Yuwen, Biqing Bao, Jing Tian, Xingrong Zhu, Lixing Weng and Lianhui Wang
Journal of Materials Chemistry A 2012 vol. 22(Issue 16) pp:7791-7796
Publication Date(Web):21 Feb 2012
DOI:10.1039/C2JM30376K
A facile wet-chemical approach for the synthesis of branched platinum nanowires (BPtNW) on reduced graphene oxide (RGO) was demonstrated. Formic acid (HCOOH) was used as the reductant for preparing BPtNW and synchronously reducing graphene oxide (GO) under the catalysis of the as-prepared BPtNW. The whole synthetic procedure was carried out easily in one pot under room temperature. The length and diameter of the Pt nanowires anchored on the RGO sheets are about 5–20 nm and 3–4 nm, respectively. GO is deoxygenated and restored to the structure of graphene successfully by the reduction of HCOOH with BPtNW as the catalyst. The BPtNW/RGO hybrids exhibit higher electrocatalytic activity and stability towards the methanol oxidation reaction than commercial Pt/C catalysts (Hispec4000). The specific methanol oxidation reaction (MOR) activity of the BPtNW/RGO hybrids was 1.154 mA cm−2 at 0.700 V, which was a nearly 3.94 times higher specific activity than that of Pt/C (Hispec4000), showing their great potential applications in fuel cells.
Co-reporter:Yu-Xiang Yang;Zhen-Hua Xu;Yu-Qian Zhang;Jing Tian
Journal of Microbiology 2012 Volume 50( Issue 6) pp:987-993
Publication Date(Web):2012 December
DOI:10.1007/s12275-012-2149-7
Quorum sensing (QS) has been a novel target for the treatment of infectious diseases. Here structural analogs of Pseudomonas aeruginosa autoinducer N-acyl homoserine lactone (AHL) were investigated for QS inhibitor (QSI) activity and a novel QSI was discovered, N-decanoyl-L-homoserine benzyl ester (C2). Virulence assays showed that C2 down-regulated total protease and elastase activities, as well as the production of rhamnolipid, that are controlled by QS in P. aeruginosa wild-type strain PAO1 without affecting growth. C2 was also shown to inhibit swarming motility of PAO1. Using a microdilution checkerboard method, we identified synergistic interactions between C2 and several antibiotics, tobramycin, gentamycin, cefepime, and meropenem. Data from real-time RT-PCR suggested that C2 inhibited the expression of lasR (29.67%), lasI (21.57%), rhlR (28.20%), and rhlI (29.03%).
Co-reporter:Yun Deng, Shu-Juan Liu, Bao-Min Zhao, Pei Wang, Qu-Li Fan, Wei Huang, Lian-Hui Wang
Journal of Luminescence 2011 Volume 131(Issue 10) pp:2166-2173
Publication Date(Web):October 2011
DOI:10.1016/j.jlumin.2011.05.021
One new three-arm star-shaped polymer was synthesized by the core-first way using atom transfer radical polymerization (ATRP) method. This polymer contained charged iridium (Ir) complex as the luminescent core and 2-(carbazol-9-yl) ethyl methacrylate as the arm repeat unit. Its structure was confirmed by elemental analysis, nuclear magnet resonance (NMR) and photoluminescence (PL). The polymer has a relatively low polydispersity index (PDI) of 1.30 with excellent thermal stability. It also possesses significant redox behavior with a HOMO level of −5.21 eV, which will be of benefit to hole-injection. The PL spectrum of the polymer in film state has a stable peak at 565 nm, however, its PL in dichloromethane solution varied with its concentration. It demonstrated effective energy transfer from the arm unit to the core in the host–guest system. This indicated that when the length of the arm is properly designed, highly luminescent materials can be achieved with emission at 565 nm.Highlights► One three-arm star-shaped polymer with Ir complex core was synthesized by ATRP method. ► Cationic Ir complex can serve as versatile templates for polymerization initiators. ► The polymer shows a pure emission at 565 nm attributed to 3MLCT transition. ► The effective energy transfer occurs from the carbazole arm to the Ir complex core.
Co-reporter:Xiaohui Li, Xiangrong Yang, Lihui Yuwen, Wenjing Yang, Lixing Weng, Zhaogang Teng, Lianhui Wang
Biomaterials (July 2016) Volume 96() pp:24-32
Publication Date(Web):July 2016
DOI:10.1016/j.biomaterials.2016.04.014
Fluorescent quantum dots (QDs) are highly promising nanomaterials for various biological and biomedical applications because of their unique optical properties, such as robust photostability, strong photoluminescence, and size-tunable fluorescence. Several studies have reported the in vivo toxicity of QDs, but their effects on the male reproduction system have not been examined. In this study, we investigated the reproductive toxicity of cadmium telluride (CdTe) QDs at a high dose of 2.0 nmol per mouse and a low dose of 0.2 nmol per mouse. Body weight measurements demonstrated there was no overt toxicity for both dose at day 90 after exposure, but the high dose CdTe affected body weight up to 15 days after exposure. CdTe QDs accumulated in the testes and damaged the tissue structure for both doses on day 90. Meanwhile, either of two CdTe QDs treatments did not significantly affect the quantity of sperm, but the high dose CdTe significantly decreased the quality of sperm on day 60. The serum levels of three major sex hormones were also perturbed by CdTe QDs treatment. However, the pregnancy rate and delivery success of female mice that mated with the treated male mice did not differ from those mated with untreated male mice. These results suggest that CdTe QDs can cause testes toxicity in a dose-dependent manner. The low dose of CdTe QDs is relatively safe for the reproductive system of male mice. Our preliminary result enables better understanding of the reproductive toxicity induced by cadmium-containing QDs and provides insight into the safe use of these nanoparticles in biological and environmental systems.
Co-reporter:Xiaohui Li, Xiangrong Yang, Lihui Yuwen, Wenjing Yang, Lixing Weng, Zhaogang Teng, Lianhui Wang
Biomaterials (July 2016) Volume 96() pp:24-32
Publication Date(Web):July 2016
DOI:10.1016/j.biomaterials.2016.04.014
Co-reporter:C. Y. Song, B. Y. Yang, W. Q. Chen, Y. X. Dou, Y. J. Yang, N. Zhou and L. H. Wang
Journal of Materials Chemistry A 2016 - vol. 4(Issue 44) pp:NaN7118-7118
Publication Date(Web):2016/09/29
DOI:10.1039/C6TB01046F
So far only a few approaches have been reported for the successful synthesis of 3D flower-like hierarchical gold nanostructures. In this paper, a facile, seedless and one-pot approach to synthesize a new class of flower-shaped gold nanoparticles with sheet-like petals has been proposed by reduction of HAuCl4 with ascorbic acid in (1-hexadecyl)trimethylammonium chloride solution, in the presence of silver nitrate (AgNO3). The growth of petals can be controlled and tuned by adjusting the amount of silver nitrate in the growth solution, and the reaction progress and evolution of the petals were monitored by time-course measurements via UV-vis-NIR spectroscopy and SEM to observe the growth mechanisms of nanoparticles. Besides, their optical properties, especially SERS performances, were also studied. These SERS-active gold nanoparticles were further utilized in the design of bright SERS tags for selectively in vitro imaging cancer cells. The results indicate that these Au NFs can be used as good SERS substrates or to design sensitive SERS sensors.
Co-reporter:Yu Gao, Yiyuan Han, Mingyue Cui, Hong Liang Tey, Lianhui Wang and Chenjie Xu
Journal of Materials Chemistry A 2017 - vol. 5(Issue 23) pp:NaN4541-4541
Publication Date(Web):2017/05/18
DOI:10.1039/C7TB00664K
Tissue adhesives have emerged as alternatives to suturing and stapling in the treatment of reconnection of injured tissues. They can be accurately applied to the regions of body that are not easy to access in a minimally invasive way without a high level of training. Recently, it was demonstrated that nanoparticles can directly glue hydrogels or tissues without the need for in situ polymerization or crosslinking. For example, silica nanoparticles can serve as connectors between tissues and exhibit adhesion even in the presence of blood. This work reports the adhesive effect of two antimicrobial nanoparticles, i.e. titanium dioxide and zinc oxide nanoparticles, between hydrogels, hydrogel/polymer, and liver tissues. These two nanoparticles exhibit comparable or even better adhesive effects in comparison to silica nanoparticles. In a skin wound mouse model, zinc oxide nanoparticles achieve successful wound closure and aesthetic wound healing, suggesting their capability as an effective antimicrobial tissue adhesive.
Co-reporter:Meng Dang, Wei Li, Yuanyi Zheng, Xiaodan Su, Xiaobo Ma, Yunlei Zhang, Qianqian Ni, Jun Tao, Junjie Zhang, Guangming Lu, Zhaogang Teng and Lianhui Wang
Journal of Materials Chemistry A 2017 - vol. 5(Issue 14) pp:NaN2634-2634
Publication Date(Web):2017/03/07
DOI:10.1039/C6TB03327J
Mesoporous organosilica nanoparticles (MONs) have attracted increasing interest for guest molecule delivery. In this work, we prepared MONs with radially oriented large pores for the first time in a water–ethanol/n-hexane biphasic reaction system. The MONs possess ethane-incorporated organosilica frameworks, large radial pores with openings of 17–78 nm, a high surface area (1219 cm2 g−1), a large pore volume (2.2 cm3 g−1), tunable diameters (124–287 nm), and excellent biocompatibility. We reveal that the formation of large pore MONs in the biphasic reaction system undergoes a surfactant-directed self-assembly following mesostructure reconstruction, providing a new mechanism for the preparation of large mesoporous nanoparticles. Also, the effects of the reaction parameters including temperature and the stirring rate on the pore size are systemically investigated. Furthermore, large pore MONs were loaded with bovine serum albumin (BSA) and small interference RNA (siRNA), which exhibit high protein loading and siRNA delivery capabilities, suggesting the potential of the MONs for biomedical applications.
Co-reporter:Lihui Yuwen, Huan Yu, Xiangrong Yang, Jiajia Zhou, Qi Zhang, Yuqian Zhang, Zhimin Luo, Shao Su and Lianhui Wang
Chemical Communications 2016 - vol. 52(Issue 3) pp:NaN532-532
Publication Date(Web):2015/10/29
DOI:10.1039/C5CC07301D
In this report, we have developed a rapid and versatile ultrasonication enhanced lithium intercalation (ULI) method to prepare single-layer transition metal dichalcogenide nanosheets (TMDC NSs, including MoS2, WS2, and TiS2) by using n-butyllithium (n-BuLi).
Co-reporter:Lei Zhang, Ying Zhang, Yanling Hu, Quli Fan, Wenjing Yang, Anran Li, Shuzhou Li, Wei Huang and Lianhui Wang
Chemical Communications 2015 - vol. 51(Issue 2) pp:NaN297-297
Publication Date(Web):2014/10/16
DOI:10.1039/C4CC06663D
We developed a novel method for the real-time monitoring of the delicate change in refractive index (RI) when DNA or RNA hybridize near a DNA-capped silver nanocube (AgNC) surface. This method offers an alternative platform in the quantitative analysis of the trace lung cancer-associated miRNAs in label-free detection.
Co-reporter:Chunyuan Song, Yanjun Yang, Boyue Yang, Linghua Min and Lianhui Wang
Journal of Materials Chemistry A 2016 - vol. 4(Issue 10) pp:NaN1817-1817
Publication Date(Web):2016/02/02
DOI:10.1039/C5TB02780B
The development of an ultrasensitive analysis technique for the combination assay of cancer associated markers is an effective method for the early detection of tumor. Herein, we report a highly sensitive and specific SERS-based sandwich immunoassay for the simultaneous detection of two protein markers associated with lung cancer, including carcinoembryonic antigen (CEA) and neuron-specific enolase (NSE). Two bright SERS tags are prepared by surface modifications of flower-like gold nanoparticles with Raman molecules and target-specific antibodies, and SERS-active magnetic nanoparticles labelled with mixed antibodies are used as immune substrates for capturing the targets and further separating the sandwich structured immune complexes from the mixture. Immunoassays for joint detection of CEA and NSE using both buffer and human serum specimens are performed and the assay results indicate that the proposed SERS-based combination assay of the two markers shows good specificity and ultrahigh sensitivity. The limit of detections of CEA and NSE in human serum specimens are 1.48 pg mL−1 and 2.04 pg mL−1, respectively. The proposed SERS immunoassay is expected to be used for multiple-marker assays of any other tumors and to provide a reliable method for the early screening of cancers in clinic.
Co-reporter:Jie Chao, Wenfang Cao, Shao Su, Lixing Weng, Shiping Song, Chunhai Fan and Lianhui Wang
Journal of Materials Chemistry A 2016 - vol. 4(Issue 10) pp:NaN1769-1769
Publication Date(Web):2016/01/13
DOI:10.1039/C5TB02135A
Detection of nucleic acid and protein targets related to human health and safety has attracted widespread attention. Surface-enhanced Raman scattering (SERS) is a powerful tool for biomarker detection because of its ultrahigh detection sensitivity and unique fingerprinting spectra. In this review, we first introduce the development of nanostructure-based SERS-active substrates and SERS nanotags, which greatly influence the performance of SERS biosensors. We then focus on recent advances in SERS biosensors for DNA, microRNA and protein determination, including label-free, labeled and multiplex analyses as well as in vivo imaging. Finally, the prospects and challenges of such nanostructure-based SERS biosensors are discussed.
Co-reporter:Zhimin Luo, Dongliang Yang, Guangqin Qi, Jingzhi Shang, Huanping Yang, Yanlong Wang, Lihui Yuwen, Ting Yu, Wei Huang and Lianhui Wang
Journal of Materials Chemistry A 2014 - vol. 2(Issue 48) pp:NaN20611-20611
Publication Date(Web):2014/11/05
DOI:10.1039/C4TA05096G
A facile solvothermal method assisted by microwave irradiation was developed for preparing nitrogen and sulfur co-doped reduced graphene oxide functionalized with fluorescent graphene quantum dots (N,S-RGO/GQDs). Graphene quantum dots (GQDs) show high fluorescence and excitation-dependent fluorescent properties. The resultant N,S-RGO/GQDs hybrids as a kind of metal-free electrocatalyst were demonstrated to have good catalytic properties with long-term operational stability and tolerance to the crossover effects of methanol for oxygen reduction via a four-electron pathway in alkaline solution. This research not only develops a low-cost, economic and scalable approach for preparing a metal-free electrocatalyst for the oxygen reduction reaction (ORR), but also produces nitrogen and sulfur co-doped graphene quantum dots (N,S-GQDs) with high fluorescent characteristics.
Co-reporter:Biqing Bao, Nanjiao Tao, Dongliang Yang, Lihui Yuwen, Lixing Weng, Quli Fan, Wei Huang and Lianhui Wang
Chemical Communications 2013 - vol. 49(Issue 90) pp:NaN10625-10625
Publication Date(Web):2013/09/24
DOI:10.1039/C3CC46605A
The authors demonstrate a smart and versatile approach for preparing multi-spectral conjugated polymers from a commercial precursor MEH–PPV without tedious synthetic modification. Multi-color CPNs with small size have also been successfully prepared using a modified-reprecipitation procedure for live cell imaging.
Co-reporter:Yanling Hu, Ying Huang, Chaoliang Tan, Xiao Zhang, Qipeng Lu, Melinda Sindoro, Xiao Huang, Wei Huang, Lianhui Wang and Hua Zhang
Inorganic Chemistry Frontiers 2017 - vol. 1(Issue 1) pp:NaN36-36
Publication Date(Web):2016/11/16
DOI:10.1039/C6QM00195E
Biosensors are powerful tools used to monitor biological and biochemical processes, ranging from clinical diagnosis to disease therapy. The huge demands for bioassays greatly promote the development of new nanomaterials as sensing platforms. Two-dimensional (2D) nanomaterials with superior properties, such as large surface areas and excellent conductivities, are excellent candidates for biosensor applications. Among them, single- or few-layered transition metal dichalcogenide (TMD) nanomaterials represent an emerging class of 2D nanomaterials with unique physical, chemical, and electronic properties. In this mini-review, we summarize the recent progress in 2D TMD nanomaterial-based biosensors for the sensitive detection of various kinds of targets, including nucleic acid, proteins, and small biomolecules, based on different sensors like optical sensors and electrochemical sensors, and bioelectronic sensors. Finally, the challenges and opportunities in this promising field are also proposed.
Co-reporter:Zhimin Luo, Lihui Yuwen, Biqing Bao, Jing Tian, Xingrong Zhu, Lixing Weng and Lianhui Wang
Journal of Materials Chemistry A 2012 - vol. 22(Issue 16) pp:
Publication Date(Web):
DOI:10.1039/C2JM30376K
Co-reporter:Chunyuan Song, Jing Chen, Yiping Zhao and Lianhui Wang
Journal of Materials Chemistry A 2014 - vol. 2(Issue 43) pp:NaN7494-7494
Publication Date(Web):2014/08/28
DOI:10.1039/C4TB01207K
In sandwich SERS immunoassays, the SERS-active substrate plays a central role in the detection sensitivity. Silver nanorod (AgNR) arrays fabricated by oblique angle deposition (OAD) provide superior analytical qualities and have been demonstrated as excellent SERS substrates. This work reports highly sensitive sandwich immunoassays performed on the OAD-AgNR substrates for the first time, utilizing 4-MBA-labeled immuno-Au nanoparticles (Im-AuNPs) as SERS tags. The aligned AgNR arrays were first deposited on glass slides by OAD, and the surface modified with gold (Au) using chloroauric acid solution via a galvanic replacement reaction. Immunoassays executed on both AgNR arrays and Au-modified AgNR arrays show higher detection sensitivity compared to that performed on self-assembled silver nanoparticles substrates. Though the AgNRs demonstrate better SERS activity than Au-modified AgNRs, the immunoassay performed on the Au-modified AgNRs exhibits higher sensitivity. Further characterization by scanning electron microscopy and fluorescence spectroscopy shows that the improved sensitivity can be attributed to the increased number of Im-AuNPs that are specifically captured on the Au-modified nanorods surface and their more uniform distribution. Concentration-dependent SERS spectra of human IgG on the Au-modified AgNR arrays reveal a good linear response range from 100 fg mL−1 to 100 ng mL−1, with an LOD of 2.5 fg mL−1.
Co-reporter:Chunhui Dai, Dongliang Yang, Wenjie Zhang, Xiao Fu, Qingmin Chen, Chengjian Zhu, Yixiang Cheng and Lianhui Wang
Journal of Materials Chemistry A 2015 - vol. 3(Issue 35) pp:NaN7036-7036
Publication Date(Web):2015/07/21
DOI:10.1039/C5TB01262G
Three new boron ketoiminate-based conjugated polymers P1, P2, and P3 were designed and synthesized through the Sonogashira coupling reaction of 4,6-bis(4-bromophenyl)-2,2-difluoro-3-phenyl-2H-1,3,2-oxazaborinin-3-ium-2-uide (M1) with 1,4-diethynyl-2,5-bis(octyloxy)benzene (M2), 3,6-diethynyl-9-octyl-9H-carbazole (M3) and 3,7-diethynyl-10-octyl-10H-phenothiazine-S,S-dioxide (M4), respectively. All the resulting polymers showed obvious aggregation-induced emission (AIE) behaviours. Interestingly, it was found that a great difference in the electron-donating abilities of the D–A type polymer linkers can lead to the unique AIE behaviour of the alternating polymers in the aggregate state, which provides us with a practical strategy to design tunable AIE-active conjugated polymers. Most importantly, studies on MCF-7 breast cancer cell imaging revealed that the nanoparticles fabricated from the conjugated polymers could serve as promising fluorescent probes with low cytotoxicity and high photostability.
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![Bis(2-methyldibenzo[f,h]quinoxaline) (acetylacetonate) iridium (III)](/data/chemimg/108400/536755-34-7_b.png)
