Co-reporter:Wan Xu, Guojiang Han, Pinyi Ma, Quanping Diao, Longbin Xu, Xin Liu, Ying Sun, Xinghua Wang, Daqian Song
Sensors and Actuators B: Chemical 2017 Volume 251(Volume 251) pp:
Publication Date(Web):1 November 2017
DOI:10.1016/j.snb.2017.05.088
•A novel “turn-on” fluorescent probe BHDB was designed and synthesized for CN− detection.•The probe featured several merits such as high sensitivity and selectivity for CN−.•HR-ESI-MS, 1H-NMR and DFT/TDDFT calculations verified the reaction mechanism.•The novel probe was successfully applied to living cells and Zebrafish.Herein, we report a novel Schiff base “turn-on” fluorescent and chromogenic probe N′-(3-(benzo[d]thiazol-2-yl)-2-hydroxybenzylidene)-4-(dimethylamino)-benzohydrazide (BHDB) for CN− detection under physiological pH, based on nucleophilic reaction of imine (CHN) and CN−, exhibiting almost 66-fold fluorescence increase and a remarkable color change from colorless to yellow. The experimentally observed changes in the spectral properties of the probe upon addition of CN− were systematically studied using high resolution electrospray ionization mass spectrometry (HR-ESI-MS), proton nuclear magnetic resonance (1H-NMR), and time-dependent density functional theory (TDDFT) calculations. Using the fluorescence spectra changes, we found a detection limit for CN− of 0.15 μmol L−1, far lower than the maximum permissive level of CN− (1.9 μmol L−1) in drinking water recommended by World Health Organization (WHO). Moreover, the novel probe demonstrated fluorescence imaging of CN− in living cells and zebrafish, suggesting its potential in clinical diagnostics.Download high-res image (123KB)Download full-size image
Co-reporter:Qiong Wu, Ying Sun, Di Zhang, Shuo Li, Yue Zhang, Pinyi Ma, Yang Yu, Xinghua Wang, Daqian Song
Biosensors and Bioelectronics 2017 Volume 96(Volume 96) pp:
Publication Date(Web):15 October 2017
DOI:10.1016/j.bios.2017.05.023
•MMWCNTs-PDA-dAb immune probe enables the enrichment of target analyte and fast mass transfer.•Hollow gold nanoparticles-PDA-based sensing platform significantly amplifies the response signal.•The detection limit of the present method for cTnI is about 1000-fold lower than that obtained by PDA-enhanced assay.•The present method presents high sensitivity and good accuracy for the detection of cTnI spiked in human serum.An ultrasensitive surface plasmon resonance (SPR) immunoassay was developed for the specific detection of human cardiac troponin I (cTnI), a principle diagnostic marker for myocardial damage. The thin gold film evaporated on a glass slate, which was employed as the SPR sensing film, was modified by hollow gold nanoparticles (HGNPs) and polydopamine (PDA) sequentially, and then was immobilized with antibodies for specific recognition of target analyte. Electronic coupling of the surface plasmon waves originating from the HGNPs and the gold film leads to the remarkable amplification of SPR response. The PDA film modified on the gold film via self-polymerization of dopamine (DA) facilitates the direct immobilization of capture antibodies (cAb). To separate and enrich the target analyte, PDA-wrapped magnetic multi-walled carbon nanotubes (MMWCNTs-PDA) were conjugated with detection antibodies (dAb) and used as the extracting agent for the magnetic extraction of cTnI in sample. Large surface area of MMWCNTs-PDA ensures its loading capacity for dAb, as well as its extraction efficiency for cTnI. By serving as the “vehicles” for fast delivering the concentrated analyte to the SPR sensing surface, MMWCNTs-PDA-dAb also overcomes the disadvantage of slow diffusion-limited mass transfer and matrix interference effect in regular patterns. The combination of the above improvements results in the significant sensitivity enhancement of the SPR immunoassay. The concentration of cTnI with minimum detectable SPR response obtained by the present assay is 1.25 ng mL−1, which is 1000-fold lower than that obtained by the traditional SPR immunoassay based on PDA-modified gold film.
Co-reporter:Wan Xu, Pinyi Ma, Quanping Diao, Longbin Xu, Xin Liu, Ying Sun, Xinghua Wang, Daqian Song
Sensors and Actuators B: Chemical 2017 Volume 252(Volume 252) pp:
Publication Date(Web):1 November 2017
DOI:10.1016/j.snb.2017.05.137
•A ratiometric fluorescent probe CEBI was designed and synthesized for SO32− detection.•The probe exhibits highly sensitivity and selectivity toward SO32−.•HR-ESI–MS, 1H NMR and DFT/TDDFT calculations verified the binding mode and reaction mechanism of CEBI with SO32−.•The probe show low cytotoxicity and can be applied in cells and zebrafish.Herein we report a new carbazole-benzo[e]indolium dye (CEBI) as a ratiometric fluorescent and chromogenic probe for sulfite (SO32−) detection based on intramolecular charge transfer (ICT) mechanism. Upon treatment with SO32−, the probe CEBI displayed a remarkable fluorescence ratiometric response (∼560-fold fluorescenc enhancement) together with a color change from red to weak red and a large shift (135 nm) in emission wavelength. The experimentally observed changes in the spectral features of the probe upon addition of SO32− were systematically studied using high resolution electrospray ionization mass spectrometry (HR-ESI–MS), proton nuclear magnetic resonance (1H NMR), and time-dependent density functional theory (TDDFT) calculations. We found a linear relationship between the ratio of fluorescence intensities at 465 nm and 600 nm (F465/F600) and SO32− concentration over the range of 0–40 μM with a detection limit of 0.025 μM. Moreover, the novel probe demonstrated fluorescence imaging of SO32− in living cells and zebrafish, suggesting its potential in clinical diagnostics.Download high-res image (115KB)Download full-size image
Co-reporter:Qiong Wu, Ying Sun, Pinyi Ma, Di Zhang, Shuo Li, Xinghua Wang, Daqian Song
Analytica Chimica Acta 2016 Volume 913() pp:137-144
Publication Date(Web):24 March 2016
DOI:10.1016/j.aca.2016.01.063
•A sensitive and versatile SPR biosensor was constructed for detection of pig IgG.•Biofunctional gold nanostars were used to amplify the response signals.•The strategy employed carboxyl-functionalized graphene oxide as biosensing substrate.•The detection limit of the proposed biosensor is 32 times lower than that of graphene oxide-based biosensor.A new high-sensitivity surface plasmon resonance (SPR) biosensor based on biofunctional gold nanostars (AuNSs) and carboxyl-functionalized graphene oxide (cGO) sheets was described. Compared with spherical gold nanoparticles (AuNPs), the anisotropic structure of AuNSs, which concentrates the electric charge density on its sharp tips, could enhance the local electromagnetic field and the electronic coupling effect significantly. cGO was obtained by a diazonium reaction of graphene oxide (GO) with 4-aminobenzoic acid. Compared with GO, cGO could immobilize more antibodies due to the abundant carboxylic groups on its surface. Testing results show that there are fairly large improvements in the analytical performance of the SPR biosensor using cGO/AuNSs-antigen conjugate, and the detection limit of the proposed biosensor is 0.0375 μg mL−1, which is 32 times lower than that of graphene oxide-based biosensor.
Co-reporter:Qiong Wu, Ying Sun, Di Zhang, Shuo Li, Xinghua Wang, Daqian Song
Biosensors and Bioelectronics 2016 Volume 86() pp:95-101
Publication Date(Web):15 December 2016
DOI:10.1016/j.bios.2016.06.035
•SPR spectroscopy is coupled with magnetic bioseparation technique for immunoassay.•Magnetic nanohybrids are served as “vehicles” for rapidly delivering target analyte.•Fe3O4-hollow gold nanohybrids as labels significantly amplify the SPR response.•Detection limit of human IgG was improved 260 times compared to routine sandwich assay.A novel surface plasmon resonance (SPR) biosensor, coupled with the magnetic bioseparation technique, was constructed and used to the determination of human IgG. Carboxyl-functionalized graphene oxide (cGO) sheet was employed as the sensing film for the efficient immobilization of capture antibody (Ab1). Nanoconjugates (FHAb2), obtained by binding detection antibody (Ab2) to the nanohybrids containing Fe3O4 nanoparticles (Fe3O4 NPs) and hollow gold sphere nanoparticles (HGNPs), were used to specifically collect the target analytes from sample solutions and serve as labels. Owing to the notable plasmonic fields spreading over inner and outer surfaces, HGNPs played key roles in amplifying the SPR response signals originating from the dielectric changes on the sensing films during the binding of Ab1 and human IgG-Ab2FH complexes. In addition, FHAb2 were also used as “vehicles” for the rapid delivery of the separated and enriched target analytes from sample solutions to the sensor surface via an external magnet. In the present method, taking advantages of the magnetic field-driven mass transfer and the significant signal amplification effect of FHAb2, the separation and analysis of human IgG in serum samples are quite effective and sensitive. The limit of detection was 1.88 ng mL−1, which is about 260-fold lower than that obtained by routine SPR biosensors with sandwich assay.
Co-reporter:Di Zhang, Ying Sun, Qiong Wu, Pinyi Ma, Hua Zhang, Yuanpeng Wang, Daqian Song
Talanta 2016 Volume 146() pp:364-368
Publication Date(Web):1 January 2016
DOI:10.1016/j.talanta.2015.08.050
•Ag nanocubes were prepared and used to amplify the SPR signal.•MPA and chitosan polymer are used to prevent Ag nanocubes from oxidation.•The process of the immobilization of antibody on the substrate was simplified.A novel surface plasmon resonance (SPR) biosensor based on Ag nanocubes/chitosan composite was fabricated for mouse IgG detection. Ag nanocubes (AgNCs) were successfully synthesized with sulfide-mediated protocol. They were characterized with transmission electron microscopy (TEM) and UV–vis adsorption spectrum. AgNCs were etched by 3-Mercaptopropinic acid (MPA) and simply mixed with chitosan and glutaraldehyde. The Ag nanocubes/chitosan composite was deposited on Au film by the spin-coating. The electronic coupling between the AgNCs and the surface plasmon wave leads to the amplification of the SPR response, which results in the sensitivity enhancement of SPR biosensor. Moreover, antibody can be immobilized on Au film with aldehyde groups via Schiff alkali reaction. The traditional SPR biosensor based on MPA shows a response for mouse IgG in the concentration range of 2.50–40.00 μg mL−1. The SPR biosensor based on AgNCs/chitosan composite shows a good response for mouse IgG in the concentration range of 0.60–40.00 μg mL−1. The limit of quantification by the biosensor based on AgNCs/chitosan composite substrate is about 4 times lower than traditional biosensor, which has proved the SPR biosensor here proposed with more sensitivity and better performance than traditional SPR biosensor.
Co-reporter:Pinyi Ma, Bo Zhang, Quanping Diao, Lin Li, Ying Sun, Xinghua Wang, Daqian Song
Sensors and Actuators B: Chemical 2016 Volume 233() pp:639-645
Publication Date(Web):5 October 2016
DOI:10.1016/j.snb.2016.04.142
A water-soluble fluorescence probe (TF) derived from fluorescein has been developed. This probe can be used to detect ClO− and Cd2+ under physiological condition based on oxidation and coordination reactions, exhibiting almost 64-fold and 4-fold fluorescence enhancement. The experimentally observed changes in the structure and electronic properties of the probe in the presence of ClO− and Cd2+ were modeled by density functional theory (DFT) and time-dependent density functional theory (TDDFT) computational calculations. Moreover, the present probe was successfully applied to the fluorescence imaging of ClO− and Cd2+ in living cells.
Co-reporter:Quanping Diao, Pinyi Ma, Linlin Lv, Tiechun Li, Xinghua Wang, Daqian Song
Spectrochimica Acta Part A: Molecular and Biomolecular Spectroscopy 2016 Volume 156() pp:15-21
Publication Date(Web):5 March 2016
DOI:10.1016/j.saa.2015.11.025
•A novel rhodamine derivative (RhC) was prepared for Cr3 + detection.•Sensing mechanism was a complexing one with binding stoichiometry of 2:1 for RhC–Cr3 + complex.•The probe was successfully applied to drinking water examination and living cell imaging.A trivalent chromium (Cr3 +) fluorescence probe (RhC) was designed and synthesized via Schiff base reaction based on rhodamine–crown ether conjugate. This probe displayed a favorable selectivity for Cr3 + over a range of other common metal ions in DMF/H2O (3:7, v/v; PBS buffer 50 mmol L− 1; pH = 6.8) solution, leading to prominent fluorescence “OFF–ON” switching of the rhodamine fluorophore. The limit of detection was calculated to be 1.5 μmol L− 1 (S/N = 3). The binding ratio of RhC–Cr3 + complex was determined to be 1:2 according to the Job's plot and HR-MS. The probe was successfully applied to examination of Cr3 + in drinking water spiked samples. The average recoveries ranged from 104.9% to 106.9% at spiked concentration level of 10.00 μmol L− 1, and the obtained results were consistent with those obtained using atomic absorption spectrometry (AAS). Moreover, bioimaging experiments showed that RhC can sense the Cr3 + in living cells with a fluorescence enhancement signal.
Co-reporter:Quanping Diao, Pinyi Ma, Linlin Lv, Tiechun Li, Ying Sun, Xinghua Wang, Daqian Song
Sensors and Actuators B: Chemical 2016 Volume 229() pp:138-144
Publication Date(Web):28 June 2016
DOI:10.1016/j.snb.2016.01.136
Based on fluorescein, a novel water-soluble and reversible fluorescent probe (Flu-Py) was designed and synthesized for the sequentially “ON–OFF–ON” fluorescent detection of Al3+ and F− in concentration range of 0–10 μmol L−1 and 0–30 μmol L−1, respectively, with high sensitivity and excellent selectivity. The detection limits for Al3+ and F− were 0.092 μmol L−1 and 0.112 μmol L−1, respectively. The binding mode and sensing mechanism of Flu-Py with Al3+ was verified by density functional theory (DFT) and time dependent density functional theory (TDDFT) calculation. The “ON-OFF–ON” fluorescent property of Flu-Py upon the addition of Al3+ and F− was utilized for the imaging of living cells.
Co-reporter:Yuanpeng Wang, Ying Sun, Bo Xu, Xinpei Li, Xinghua Wang, Hanqi Zhang, Daqian Song
Analytica Chimica Acta 2015 Volume 888() pp:67-74
Publication Date(Web):12 August 2015
DOI:10.1016/j.aca.2015.07.028
•Magnetic ionic liquid was first used as a microextraction solvent for fatty solid samples.•Magnetic separation of the ionic liquid met the requirement of rapid analysis.•The performances achieved by the present method were acceptable.A novel method was developed for the determination of six triazine herbicides from oilseeds by matrix solid-phase dispersion combined with magnetic ionic liquid dispersive liquid–liquid microextraction (MSPD-MIL-DLLME), followed by ultrafast liquid chromatography with ultraviolet detection (UFLC-UV). The MIL, 1-butyl-3-methylimidazolium tetrachloroferrate ([C4mim][FeCl4]), was used as the microextraction solvent to simplify the extraction procedure by magnetic separation. The effects of several important experimental parameters, including type of dispersant, ratio of sample to dispersant, type and volume of collected elution solvent, type and volume of MIL, were investigated. Using the present method, UFLC-UV gave the limits of detection (LODs) of 1.20–2.72 ng g−1 and the limits of quantification (LOQs) of 3.99–9.06 ng g−1 for triazine herbicides. The recoveries were ranged from 82.9 to 113.7% and the relative standard deviations (RSDs) were equal or lower than 7.7%. The present method is easy-to-use and effective for extraction of triazine herbicides from oilseeds and shows the potentials of practical applications in the treatment of the fatty solid samples.
Co-reporter:Yuanpeng Wang, Ying Sun, Bo Xu, Xinpei Li, Rui Jin, Hanqi Zhang, Daqian Song
Journal of Chromatography A 2014 Volume 1373() pp:9-16
Publication Date(Web):19 December 2014
DOI:10.1016/j.chroma.2014.11.009
•DLLME was used for preconcentration of triazine herbicides from vegetable oils.•Magnetic ionic liquid was select as a novel microextraction solvent of DLLME.•Magnetic separation of the ionic liquid met the requirement of rapid analysis.•The performances were acceptable in comparison to existing methods.Magnetic ionic liquid-based dispersive liquid–liquid microextraction (MIL-based DLLME) was developed for extracting triazine herbicides from vegetable oils. The MIL, 1-hexyl-3-methylimidazolium tetrachloroferrate ([C6mim] [FeCl4]), was used as the microextraction solvent. The magnetic separation time was shortened by simply mixing carbonyl iron powder with the MIL in the sample after DLLME. The effects of several important experimental parameters, including the amount of MIL, the time of ultrasonic extraction, the type and the volume of cleanup solvent were investigated. The MIL-based DLLME coupled with liquid chromatography gave the limits of detection of 1.31–1.49 ng mL−1 and limits of quantification of 4.33–4.91 ng mL−1 for triazine herbicides. When the present method was applied to the analysis of vegetable oil samples, the obtained recoveries were in the range of 81.8–114.2% and the relative standard deviations were lower than 7.7%. Compared with existing methods, the performances achieved by the present method were acceptable.
Co-reporter:Chunzhu Jiang, Ying Sun, Xi Yu, Yan Gao, Lei Zhang, Yuanpeng Wang, Hanqi Zhang, Daqian Song
Journal of Chromatography B 2014 Volumes 947–948() pp:49-56
Publication Date(Web):1 February 2014
DOI:10.1016/j.jchromb.2013.12.008
•C18-UMS NPs were successfully synthesized.•Aromatic amines in urine samples were extracted by C18-UMS NPs.•C18-UMS NPs can be recycled.•The factors which can influence extraction efficiencies were investigated.In this paper, a novel method using C18-functional ultrafine magnetic silica nanoparticles (C18-UMS NPs) as adsorbents was developed for rapid extraction and enrichment of aromatic amines from urine. C18-UMS NPs were prepared by chemical coprecipitation, silanization and alkylation. The aromatic amines can be adsorbed on C18-UMS NPs and isolated easily from the matrix with an external magnetic field. After desorption with acetonitrile, the aromatic amines were determined by ultra fast liquid chromatography. The experimental parameters, such as pH value of sample solution, amount of C18-UMS NPs, extraction time, type and volume of desorption solvent, and desorption time were optimized. The analytical performances of the present method were also evaluated. The limits of detection for 1-aminonaphthalene, 4-aminobiphenyl, 4,4′-diaminodiphenylmethane and 4-aminophenylthioether were 1.3, 0.88, 1.1 and 1.1 ng mL−1, respectively. The results showed that the present method was simple, highly efficient and rapid for the extraction and enrichment of aromatic amines from urine.
Co-reporter:Hua Zhang, Ying Sun, Shang Gao, Hanqi Zhang, Jia Zhang, Yu Bai, Daqian Song
Talanta 2014 Volume 125() pp:29-35
Publication Date(Web):1 July 2014
DOI:10.1016/j.talanta.2014.02.036
•A wavelength modulation SPR biosensor based on GNR-Fe3O4 nanohybrids was developed.•The GNR-Fe3O4 nanohybrids simplified the experimental procedure.•The nanohybrids were proved to be an ideal support for sensitive detection of biomolecule.•The sensentivity of SPR biosensor was enhanced when the nanohybrids were applied.A wavelength modulation surface plasmon resonance (SPR) biosensor based on gold nanorods-Fe3O4 (GNR-Fe3O4) nanohybrids was developed for the determination of mouse IgG. The premade negatively charged Fe3O4 nanoparticles were coated on the surface of positively charged GNRs through electrostatic interaction. The synthetic method was simple, quick and easy operation. The aldehyde group functionalized GNR-Fe3O4 nanohybrids possess unique magnetic property, exceptional optical property and good biocompatibility, which can be used as immobilization matrix for biomolecules. The magnetic nanohybrids can be easily immobilized on the surface of SPR biosensor chip with a magnetic pillar, which simplifies the experimental procedure. The effects of GNR-Fe3O4 nanohybrids on the sensitivity of SPR biosensor were also studied. The SPR biosensor based on GNR-Fe3O4 nanohybrids shows a good response to mouse IgG in the concentration range of 0.15–40.00 μg mL−1, while the biosensor based on MPA and Fe3O4 nanoparticles show a good response to mouse IgG in the concentration range of 2.50–40.00 μg mL−1 and 1.25–40.00 μg mL−1, respectively. As a result, when GNR-Fe3O4 nanohybrids were used in SPR biosensor, the sensitivity for the determination of mouse IgG is significantly enhanced.
Co-reporter:Yuanpeng Wang, Ying Sun, Yan Gao, Bo Xu, Qiong Wu, Hanqi Zhang, Daqian Song
Talanta 2014 Volume 119() pp:268-275
Publication Date(Web):15 February 2014
DOI:10.1016/j.talanta.2013.11.007
•dSPE of pyrethroids in tea drinks by polyaninile-coated magnetic particles is feasible.•The magnetic particles with a bowl-shaped morphology were synthesized.•The microbowls were used as the adsorbent in magnetic solid phase extraction.•The magnetic particles can be reused after easy washing.The polyaniline-coated magnetic particles with bowl-shaped morphology (Fe3O4/C/PANI microbowls) were successfully prepared and characterized by scanning electron microscopy, transmission electron microscopy and vibrating sample magnetometry. The prepared microbowls were used as the magnetic adsorbent in dispersive solid phase extraction of five pyrethroids, including cyhalothrin, beta-cypermethrin, esfenvalerate, permethrin and bifenthrin in plain tea drinks. The effects of experiment factors, including amount of Fe3O4/C/PANI microbowls, pH value, ultrasound extraction time and desorption conditions, were investigated. The extraction recoveries obtained with 8 mg of magnetic microbowls were satisfactory, and the microbowls can be reused after easy washing. Thus, a simple, selective and effective method for the determination of the pyrethroids was established successfully. The results showed that the method had good linearity (r=0.9992–0.9998), and the limits of detections (LODs) were from 0.025 to 0.032 ng mL−1. The intra-day and inter-day relative standard deviations (RSDs) were in the range of 2.4–6.1% and 3.5–8.8%, respectively. Recoveries obtained by analyzing the real tea drinks were in the range of 72.1–118.4%.
Co-reporter:Jia Zhang, Ying Sun, Qiong Wu, Yan Gao, Hua Zhang, Yu Bai, Daqian Song
Colloids and Surfaces B: Biointerfaces 2014 Volume 116() pp:211-218
Publication Date(Web):1 April 2014
DOI:10.1016/j.colsurfb.2014.01.003
•A novel SPR biosensor based on graphene oxide and Au bipyramids is proposed.•The GO sheets function as ideal platform for the immobilization of antibody.•Au bipyramid nanoparticles are proved to be promising sensitivity enhancer.•The present biosensor has the highest sensitivity among four types of biosensors.A sensitive and selective wavelength-modulation surface plasmon resonance (SPR) biosensor based on graphene oxide (GO) and Au bipyramids (AuBPs) is reported for determination of bovine IgM. GO sheets with lengths of 100–300 nm are synthesized and assembled on amine-modified Au film. The large surface area and abundant functional groups of GO allow the efficient immobilization of antibody. AuBPs are nanoparticles with a penta-twinned crystal structure, which have a sharp localized surface plasmon resonance (LSPR) band because of their high monodispersity. In the optimal conditions, the GO-based biosensor with AuBPs as sensitivity enhancers shows a satisfactory response to bovine IgM in the concentration range of 0.03–32 μg mL−1. For contrast, traditional biosensor, GO-based biosensor and GO-based biosensor with Au nanorods (AuNRs) as sensitivity enhancers for antigen detection were also investigated. Consequently, the as-prepared GO sheets function as promising support for antibody and GO-based SPR biosensor using AuBPs as enhancers has the highest sensitivity among the four types of biosensors.
Co-reporter:Pinyi Ma;Fanghui Liang;Qingqing Yang;Di Wang;Ying Sun
Microchimica Acta 2014 Volume 181( Issue 9-10) pp:975-981
Publication Date(Web):2014 July
DOI:10.1007/s00604-014-1196-7
We have developed a surface-enhanced Raman scattering (SERS) probe for the determination of mercury(II) using methimazole-functionalized and cyclodextrin-coated silver nanoparticles (AgNPs). These AgNPs in pH 10 solution containing sodium chloride exhibit strong SERS at 502 cm−1. Its intensity strongly decreases in the presence of Hg(II). This effect serves as the basis for a new method for the rapid, fast and selective determination of trace Hg(II). The analytical range is from 0.50 μg L−1 to 150 μg L−1, and the limit of detection is 0.10 μg L−1. The influence of 11 metal ions commonly encountered in environmental water samples was found to be quite small. The method was applied to the determination of Hg(II) in spiked water samples and gave recoveries ranging from 98.5 to 105.2 % and with relative standard deviations of <3.5 % (n = 5). The total analysis time is <10 min for a single sample.
Co-reporter:Jia Zhang, Ying Sun, Hua Zhang, Bo Xu, Hanqi Zhang, Daqian Song
Analytica Chimica Acta 2013 Volume 769() pp:114-120
Publication Date(Web):26 March 2013
DOI:10.1016/j.aca.2013.01.034
This paper reports the utilization of triangular silver nanoplates (TSNPs) to enhance the sensitivity of surface plasmon resonance (SPR) biosensor. TSNPs modified with 3-mercaptopropinic acid (MPA) were simply mixed with chitosan and glutaraldehyde to form TSNPs/chitosan composite. The composite was deposited on Au film as immobilization substrate for SPR biosensor. The novel structures of TSNPs are preserved against etching by MPA and chitosan polymer. Moreover, chitosan cross-linked by glutaraldehyde enables antibody to be immobilized on fabricated substrate directly via Schiff alkali reaction. In the optimized conditions, the resulting biosensor based on TSNPs/chitosan composite shows a satisfactory response to bovine IgG in the concentration range of 0.075–40.00 μg mL−1. While the biosensor based on chitosan without TSNPs shows a response in the concentration range of 0.6–40 μg mL−1 and the biosensor based on Au film shows a response in the concentration range of 2.5–40 μg mL−1. The experiment results show that the sensitivity of SPR biosensor based on TSNPs/chitosan composite was significantly enhanced and the immobilization procedure of antibody was simplified.Graphical abstractHighlights► Triangular silver nanoplates were prepared and used to amplify the SPR signal. ► Triangular silver nanoplates are preserved by MPA and chitosan polymer. ► The proposed substrate immobilizes antibodies directly without modification. ► The LOQ of present method for analyte is 32 times lower than that based on Au film.
Co-reporter:Jia Zhang, Ying Sun, Qiong Wu, Hua Zhang, Yu Bai and Daqian Song
Analyst 2013 vol. 138(Issue 23) pp:7175-7181
Publication Date(Web):19 Sep 2013
DOI:10.1039/C3AN01553J
A sensitive and selective wavelength modulation surface plasmon resonance (SPR) biosensor is reported with Au nanoparticle decorated graphene oxide (GO) as an enhanced sensing platform. GO sheets possess favourable water dispersibility, good biocompatibility and high loading capacity. An Au–GO composite with the Au spheres size of 15–20 nm was synthesized and modified with staphylococcal protein A (SPA). The as-prepared composite assembles directly onto the Au film surface of the SPR sensor. Meanwhile, SPA specifically recognizes and binds the Fc portion of antibodies, contributing to highly oriented antibody immobilization on the chip surface without any antibody modification. Consequently, the biosensor based on the SPA modified Au–GO composite exhibits a satisfactory response to rabbit IgG in the concentration range of 0.1–50 μg mL−1, while the biosensor based on the sole SPA layer for antibody immobilization shows a response in the concentration range of 1.6–50 μg mL−1. Experimental results show that the SPA modified Au–GO composite can be successfully used for the signal amplification of immunosensors, thereby improving the sensitivity and obviating the need of chemical modification of the antibody.
Co-reporter:Yuanpeng Wang, Ying Sun, Yun Wang, Chunzhu Jiang, Xi Yu, Yan Gao, Hanqi Zhang and Daqian Song
Analytical Methods 2013 vol. 5(Issue 6) pp:1399-1406
Publication Date(Web):17 Jan 2013
DOI:10.1039/C3AY26357F
The magnetic mesoporous microsphere-based extraction method coupled with ultra fast liquid chromatography (UFLC) was applied for the extraction and determination of Sudan dyes in environmental water samples. Fe3O4@SiO2 microspheres consisting of a Fe3O4 particle core and an ordered mesoporous silica shell were used. The Fe3O4 particles were prepared simply by a solvothermal reduction method. The mesoporous silica was prepared and coated on the Fe3O4 particles via a surfactant-templating approach by stirring at room temperature. The obtained Fe3O4@SiO2 microspheres possess superparamagnetism and a good mesoporous structure. The experimental parameters, including the amount of Fe3O4@SiO2 microspheres, the pH value of sample solution, extraction time, separation time, elution solvent, volume of elution solvent and elution time, were optimized. Under the optimized conditions, Fe3O4@SiO2 microspheres were successfully used to extract Sudan dyes in the environmental water samples and the enrichment factor is 500-fold. The result showed that the method had good linearity (r = 0.990–0.997), and the limits of detection (LODs) were from 0.082 to 0.12 ng ml−1. Recoveries obtained by analyzing the five spiked water samples were in the range of 87.10–111.4% and the intra-day and inter-day relative standard deviations (RSDs) were between 0.590 and 7.94%. The results indicated that the novel method could be applied successfully for the determination of Sudan dyes in environmental water samples.
Co-reporter:Yan Gao, Ying Sun, Yuanpeng Wang, Jia Zhang, Bo Xu, Hanqi Zhang and Daqian Song
Analytical Methods 2013 vol. 5(Issue 16) pp:4112-4118
Publication Date(Web):13 Jun 2013
DOI:10.1039/C3AY40638E
A practical, simple and rapid method based on matrix solid phase dispersion (MSPD) extraction and ultrafast liquid chromatography (UFLC) was developed and validated for the simultaneous isolation, purification and quantification of geniposide from the fruit of Gardenia jasminoides Ellis. The experimental parameters such as the type of dispersing sorbent and elution solvent, the volume of elution solvent, the ratio of sorbent/sample and the particle size of sample were first studied separately by a univariate method. Then relevant parameters were evaluated by orthogonal screening to determine the optimal operation conditions. The optimal conditions were 0.5 g of fruit of Gardenia jasminoides Ellis, 0.75 g of Celite (diatomaceous earth) as dispersing sorbent and a volume of 25 mL of aqueous solutions containing 70% methanol as the elution solvent. The feasibility of the method was evaluated by investigating linearity, accuracy, precision, real sample analysis, limit of detection (LOD) and limit of quantification (LOQ). The LOD and LOQ were 0.026 and 0.087 μg mL−1, respectively. The recoveries ranged from 87.9% to 104.8% at two spiking levels with relative deviations (RSDs) ranging from 0.6% to 3.9%. Compared with the conventional extraction methods, such as ultrasound-assisted extraction (UAE) and Soxhlet extraction (SE), the proposed method is quicker and more effective.
Co-reporter:Jia Zhang, Ying Sun, Bo Xu, Hua Zhang, Yan Gao, Hanqi Zhang, Daqian Song
Biosensors and Bioelectronics 2013 Volume 45() pp:230-236
Publication Date(Web):15 July 2013
DOI:10.1016/j.bios.2013.02.008
A surface plasmon resonance (SPR) biosensor based on graphene oxide (GO) decorated with gold nanorod (AuNR)–antibody conjugates was developed. Compared with traditional SPR biosensor, GO sheets were assembled on the amino-modified Au film via electrostatic interaction, and then AuNR–antibody conjugates were immobilized via carbodiimide-assisted amidation reaction. The abundant oxygen-containing functional groups, large specific surface area and friendly biocompatibility of GO sheets are beneficial to the immobilization of AuNR–antibody conjugates. Meanwhile, AuNRs are anchored to the GO surface through antibody and function as enhancers for the transferrin determination, which greatly enhance the sensitivity of the detection. As a result, the present biosensor shows a satisfactory response to transferrin in the concentration range of 0.0375–40.00 μg mL−1. The lowest concentration of transferrin that can be determined by this method is about 32-fold lower than that obtained with the sensor based on Au film. This design affords a facile method of controlling the assembly of AuNRs on the GO sheets and can be easily extended to other protein detection by preparing corresponding AuNR–antibody conjugates.Highlights► A SPR biosensor based on GO decorated with AuNR–antibody conjugates was developed. ► GO was assembled on amine-modified Au film for immobilization of conjugates. ► AuNRs were anchored to the GO surface through antibody and acted as enhancers. ► The proposed method permitted 32 times enhancement in sensitivity.
Co-reporter:Chunzhu Jiang, Ying Sun, Xi Yu, Yan Gao, Lei Zhang, Yuanpeng Wang, Hanqi Zhang, Daqian Song
Talanta 2013 Volume 114() pp:167-175
Publication Date(Web):30 September 2013
DOI:10.1016/j.talanta.2013.04.004
•LSE coupled with MSPE has been developed.•The present method based on MSPE can extract pyrethroids from solid matrix.•C18-UMS NPs can be recycled.In this study, liquid–solid extraction coupled with magnetic solid-phase extraction was successfully developed for the extraction of pyrethroid residues in vegetable samples. The analytes were determined by ultra fast liquid chromatography. The pyrethroids were extracted by liquid–solid extraction and then adsorbed onto magnetic adsorbent. Magnetic adsorbent, C18-functionalized ultrafine magnetic silica nanoparticles, was synthesized by chemical coprecipitation, silanization and alkylation. The analytes adsorbed onto the magnetic adsorbent can be simply and rapidly isolated from sample solution with a strong magnet on the bottom of the extraction vessel. The extraction parameters, such as liquid–solid extraction solvent, liquid–solid extraction time, the amount of magnetic adsorbent, magnetic solid-phase extraction time and magnetic solid-phase extraction desorption solvent, were optimized to improve the extraction efficiency. The analytical performances of this method, including linear range, detection limit, precision, and recovery were evaluated. The limits of detection for pyrethroid were between 0.63 and 1.2 ng g−1. Recoveries obtained by analyzing the four spiked vegetable samples were between 76.0% and 99.5%. The results showed that the present method was a simple, accurate and high efficient approach for the determination of pyrethroids in the vegetable samples.
Co-reporter:Xi Yu;Ying Sun;Chun-Zhu Jiang;Yan Gao;Yuan-Peng Wang;Han-Qi Zhang ;Da-Qian Song
Journal of Separation Science 2012 Volume 35( Issue 23) pp:3403-3411
Publication Date(Web):
DOI:10.1002/jssc.201200555
A nanocomposite of polystyrene-coated magnetic nanoparticles was successfully synthesized and employed as adsorbent for magnetic solid-phase extraction of four Sudan dyes (I, II III, and IV) in red wines, juices, and mature vinegars. The prepared magnetic nanoparticles with highly hydrophobic properties have excellent adsorption capacity for these lipophilic Sudan dyes. Extraction conditions were optimized. Experimental results showed that the recoveries of the four Sudan dyes were very satisfactory when 70 mg of polystyrene-coated magnetic nanoparticles were used and the extraction could be completed within 20 min. It was proved that these magnetic nanoparticles can be reused after an easy washing process. By coupling the magnetic solid-phase extraction with ultrafast liquid chromatography-ultraviolet spectrometry, a rapid, green, effective, and sensitive method for the determination of Sudan dyes was developed. The LOD for Sudan I, Sudan II, Sudan III, and Sudan IV were 0.0039, 0.0063, 0.0057, and 0.017 ng/mL, respectively. Recoveries obtained by analyzing spiked water samples at three concentration levels (0.1, 1.0, and 10.0 ng/mL) were between 76.3 and 96.6%. The intra- and interday RSDs for the analytes were lower than 9.6%.
Co-reporter:Xiu-Min Sun, Ying Sun, Li-Wei Wu, Chun-Zhu Jiang, Xi Yu, Yan Gao, Li-Ying Wang and Da-Qian Song
Analytical Methods 2012 vol. 4(Issue 7) pp:2074-2080
Publication Date(Web):04 Apr 2012
DOI:10.1039/C2AY25056J
A vortex-assisted ionic liquid microextraction method coupled with ultra fast liquid chromatographic separation and detection was developed for the analysis of three aromatic amines, 4-chloroaniline, 1-naphthylamine and 4-aminobiphenyl, in environmental water samples. 1-Hexyl-3-methylimidazolium hexafluorophosphate [C6MIM][PF6] was used as the extraction solvent as it can disperse in water completely and quickly with the aid of vortex mixing. A dispersive solvent was not required. Several parameters such as type and volume of extraction solvent, vortex velocity, extraction time, centrifugation time, pH of sample solution and ionic strength in sample solution were investigated. Under the optimized conditions, the intra-day and inter-day precision of the proposed method were 2.3–3.5% (n = 5) and 2.8–5.3% (n = 5), respectively. The limits of detection and quantification were in the range of 0.24–0.57 μg L−1 and 0.80–1.90 μg L−1, respectively. The proposed method was applied in the determination of three aromatic amines in several real water samples. Acceptable recoveries of the analytes, ranging from 79% to 111% (the relative standard deviations ≤6.0%), were obtained.
Co-reporter:Hua Zhang, Ying Sun, Jing Wang, Jia Zhang, Hanqi Zhang, Hao Zhou, Daqian Song
Biosensors and Bioelectronics 2012 Volume 34(Issue 1) pp:137-143
Publication Date(Web):15 April 2012
DOI:10.1016/j.bios.2012.01.032
A novel nanocomposite Fe3O4–Au nanorod (AuNR) was prepared and used as the substrate in the surface plasmon resonance (SPR) biosensor to detect goat IgM. Fe3O4–AuNR nanocomposites were synthesized by a method of seed-mediated growth, and further characterized by molecular absorption spectroscopy, transmission electronic microscopy (TEM), energy-dispersive spectroscopy (EDS) and X-ray photoelectron spectroscopy (XPS). The nanocomposites exhibit both magnetic property and exceptional optical property, which are beneficial to the antibody immobilization and the sensitivity of detection. The sensing membrane can be regenerated easily and the experimental procedure is simplified. Moreover, the Au nanorods show two plasmon resonance wavelengths defined as transverse mode and longitudinal mode, and the longitudinal plasmon wavelengths are more sensitive to the changes in the dielectric properties of the surroundings. Fe3O4–AuNR nanocomposites got a high sensitivity in detection of antibody–antigen immunoassay. In the optimal conditions, the biosensor based on Fe3O4–AuNR nanocomposites exhibits a satisfactory response to goat IgM in the concentration range of 0.15–40.00 μg mL−1. However, the biosensor without Fe3O4–AuNR nanocomposites shows a response to goat IgM in the concentration range of 1.25–40.00 μg mL−1. As a result, the sensitivity of the biosensor based on Fe3O4–AuNR nanocomposites is enhanced significantly.Highlights► A novel nanocomposite Fe3O4–Au nanorod (AuNR) was prepared and applied to the surface plasmon resonance biosensor. ► The Fe3O4–AuNR nanocomposites could be easily immobilized on the surface of Au film with a magnetic pillar. ► The biosensor based on Fe3O4–AuNR nanocomposites was easy to be regenerated. ► The limit of quantification (LOQ) obtained with the Fe3O4–AuNR nanocomposites is 8 times lower than that obtained with unmodified biosensor film.
Co-reporter:Chunzhu Jiang, Ying Sun, Xi Yu, Lei Zhang, Xiumin Sun, Yan Gao, Hanqi Zhang, Daqian Song
Talanta 2012 Volume 89() pp:38-46
Publication Date(Web):30 January 2012
DOI:10.1016/j.talanta.2011.11.052
In this study, the new C18-functionalized ultrafine magnetic silica nanoparticles (C18-UMS NPs) were successfully synthesized and applied for extraction of sudan dyes in water samples based on the magnetic solid-phase extraction (MSPE). The extraction and concentration were carried out in one step by blending C18-UMS NPs and water samples. The sudan dyes adsorbed C18-UMS NPs were isolated from the matrix easily with an external magnetic field. After desorption the quantitation of sudan dyes was done by ultra fast liquid chromatography (UFLC). Satisfactory extraction recovery can be obtained with only 50 mg C18-UMS NPs. The effects of experimental parameters, including the amount of the nanoparticles, extraction time, pH value, desorption solvent, volume of desorption solvent and desorption time were investigated. The limits of detection for sudan I, II, III and IV were 0.066, 0.070, 0.12 and 0.12 ng mL−1, respectively. Recoveries obtained by analyzing the six spiked water samples were between 68% and 103%.Highlights► C18-UMS NPs were successfully synthesized. ► C18-UMS NPs have small diameter and can be easily dispersed in aqueous samples. ► Sudan dyes in large volume of water samples were extracted by C18-UMS NPs. ► C18-UMS NPs can be recycled. ► The factors which can influence extraction efficiencies were investigated.
Co-reporter:Xi Yu, Ying Sun, Chunzhu Jiang, Xiumin Sun, Yan Gao, Yuanpeng Wang, Hanqi Zhang, Daqian Song
Talanta 2012 Volume 98() pp:257-264
Publication Date(Web):30 August 2012
DOI:10.1016/j.talanta.2012.07.022
In this study, the polystyrene-coated magnetic nanoparticles (MNPs/PSt) were successfully prepared and characterized by Fourier transform infrared spectroscopy, transmission electron microscopy and vibrating sample magnetometry. The as-prepared MNPs/PSt were used as the adsorbent in magnetic solid phase extraction of five pyrethroids, including lambda-cyhalothrin, deltamethrin, esfenvalerate, permethrin, bifenthrin, in environmental water samples. The five pyrethroids were determined by ultra fast liquid chromatography-ultraviolet spectrometry. The influencing factors, including amount of MNPs/Pst, extraction time, pH value, type and volume of desorption solvent and desorption time, were examined and optimized. The extraction recoveries obtained with merely 50 mg of MNPs/Pst were very satisfactory. The whole extraction process could be completed within 0.5 h. The MNPs/PSt can be reused after an easy washing process. Thus, a simple, green, economical, time saving and effective method for pyrethroids analysis in environmental water samples was established. A high enrichment factor of 500 was achieved and the limits of detection for lambda-cyhalothrin, deltamethrin, esfenvalerate, permethrin, bifenthrin were 0.015±0.001 ng mL−1, 0.012±0.001 ng mL−1, 0.026±0.001 ng mL−1, 0.020±0.001 ng mL−1, 0.013±0.001 ng mL−1, respectively. Recoveries obtained by analyzing spiked water samples at three concentration levels (0.100±0.001 ng mL−1, 1.000±0.001 ng mL−1, 10.000±0.001 ng mL−1) were between 78.97±8.38% and 96.05±8.38%. The standard curves for the five pyrethroids showed good linearity with the correlation coefficients in the range of 0.9994–0.9999. The intra-day and inter-day precision were satisfactory with the RSDs in the range of 2.05–5.52% and 2.73–8.38%, respectively.Highlights► Polystyrene-coated magnetic nanoparticles (MNPs/PSt) were prepared. ► The MNPs/PSt were used for magnetic solid-phase extraction (MSPE) of pyrethroids. ► The MSPE showed good selectivity and efficiency. ► The MNPs/PSt can be recycled.
Co-reporter:Jing Wang, Daqian Song, Liying Wang, Hua Zhang, Hanqi Zhang, Ying Sun
Sensors and Actuators B: Chemical 2011 Volume 157(Issue 2) pp:547-553
Publication Date(Web):20 October 2011
DOI:10.1016/j.snb.2011.05.020
A novel method for detecting human IgG is reported, which is based on Au/Ag alloy nanocomposites for amplifying surface plasmon resonance response. Au/Ag alloy nanocomposites were characterized in detail by transmission electron microscopy (TEM), UV–vis absorption spectroscopy and X-ray photoelectron spectroscopy (XPS). Covalent immobilization of about 24 nm diameter of Au/Ag alloy nanocomposites on the Au film results in a large shift in resonance wavelength, which is due to the increase of the thickness of the sensing membrane, high dielectric constant of Au/Ag nanoparticles, and electromagnetic coupling between Au/Ag alloy nanocomposites and Au film. The SPR biosensor based on Au/Ag alloy nanocomposites exhibits a satisfactory response for human IgG in the concentration range of 0.15–40.00 μg mL−1. While the biosensor based on Au nanoparticles shows a response in the concentration range of 0.30–20.00 μg mL−1 and the biosensor based on Au film shows a response for human IgG in the concentration range of 1.25–20.00 μg mL−1.
Co-reporter:Liying Wang, Ying Sun, Jing Wang, Jian Wang, Aimin Yu, Hanqi Zhang, Daqian Song
Colloids and Surfaces B: Biointerfaces 2011 Volume 84(Issue 2) pp:484-490
Publication Date(Web):1 June 2011
DOI:10.1016/j.colsurfb.2011.02.003
In this paper, surface plasmon resonance biosensors based on magnetic core/shell Fe3O4/SiO2 and Fe3O4/Ag/SiO2 nanoparticles were developed for immunoassay. With Fe3O4 and Fe3O4/Ag nanoparticles being used as seeding materials, Fe3O4/SiO2 and Fe3O4/Ag/SiO2 nanoparticles were formed by hydrolysis of tetraethyl orthosilicate. The aldehyde group functionalized magnetic nanoparticles provide organic functionality for bioconjugation. The products were characterized by scanning electronic microscopy (SEM), transmission electronic microscopy (TEM), FTIR and UV–vis absorption spectrometry. The magnetic nanoparticles possess the unique superparamagnetism property, exceptional optical properties and good compatibilities, and could be used as immobilization matrix for goat anti-rabbit IgG. The magnetic nanoparticles can be easily immobilized on the surface of SPR biosensor chip by a magnetic pillar. The effects of Fe3O4/SiO2 and Fe3O4/Ag/SiO2 nanoparticles on the sensitivity of SPR biosensors were also investigated. As a result, the SPR biosensors based on Fe3O4/SiO2 nanoparticles and Fe3O4/Ag/SiO2 nanoparticles exhibit a response for rabbit IgG in the concentration range of 1.25–20.00 μg ml−1 and 0.30–20.00 μg ml−1, respectively.Graphical abstractSchematic illustration of the formation of Fe3O4/SiO2 (a) and Fe3O4/Ag/SiO2 (b) magnetic nanoparticles.Research highlights► Magnetic core/shell Fe3O4/SiO2 and Fe3O4/Ag/SiO2 nanoparticles were synthesized. ► Two types of SPR biosensors based on magnetic nanoparticles were prepared. ► The magnetic nanoparticles can be easily immobilized on the surface of SPR biosensor. ► The magnetic nanoparticles could enhance the sensitivity of the SPR biosensor.
Co-reporter:Liying Wang, Ying Sun, Jian Wang, Jing Wang, Aimin Yu, Hanqi Zhang, Daqian Song
Journal of Colloid and Interface Science 2010 Volume 351(Issue 2) pp:392-397
Publication Date(Web):15 November 2010
DOI:10.1016/j.jcis.2010.07.050
A surface plasmon resonance biosensor based on ZnO–Au nanocomposites was developed for the detection of rabbit IgG. The ZnO–Au nanocomposites can bind protein by covalent attachment to construct a probe for target analyte. The probe with unique optical properties and good biocompatibility could enhance the sensitivity of SPR biosensor. Under the optimized conditions, the biosensor based on ZnO–Au nanocomposites exhibits a satisfactory response to rabbit IgG in the concentration range of 0.15–20.00 μg ml−1. For comparison, the biosensor based on Au film and the biosensor based on Au nanoparticles were also studied for the detection of rabbit IgG. The biosensor based on Au film shows a response to rabbit IgG in the concentration range of 2.50–20.00 μg ml−1. The biosensor based on Au nanoparticles shows a response in the concentration range of 0.30–20.00 μg ml−1. The biosensor based on ZnO–Au nanocomposites was therefore found to be the most sensitive of the three types of biosensors. The lowest concentration of rabbit IgG that can be determined by the proposed biosensor is about 16-fold lower than that of the biosensor based on Au film alone.Graphical abstractSchematic illustration of ZnO–Au nanocomposites coupled with antigen.Research highlights► Water-soluble ZnO–Au nanocomposites were synthesized. ► A protein probe based on ZnO–Au nanocomposites was constructed. ► The protein probe was used to modify the SPR biosensor. ► The protein probe could enhance the sensitivity of the SPR biosensor.
Co-reporter:Chunzhu Jiang;Ying Sun;Xiaonan Zhu;Yan Gao;Liying Wang;Jian Wang;Liwei Wu
Journal of Separation Science 2010 Volume 33( Issue 17-18) pp:2784-2790
Publication Date(Web):
DOI:10.1002/jssc.201000148
Abstract
Solvent-free microwave extraction coupled with headspace single-drop microextraction was developed for extracting the essential oils from Eugenia caryophyllata Thunb. Carbonyl iron powders were mixed with the sample to extract essential oils from the dried plant materials and single-drop solvent was used to simultaneously extract essential oils from the headspace. The single-drop of decane was suspended from the tip of a microsyringe and exposed to the headspace above the sample. After the extraction was finished, the single-drop was injected into gas chromatographic system and analyzed by GC-MS. The effects of the experimental parameters, including microwave power, microwave irradiation time, the ratio of carbonyl iron powder to sample, extraction solvent, single-drop volume and extraction time, were investigated. Sixteen compounds in the essential oils of E. caryophyllata T. were obtained and identified. The constituents of essential oils obtained by hydro-distillation and solvent-free microwave extraction–headspace single-drop microextraction were not obviously different. Compared with hydro-distillation, the proposed method required shorter extraction time and less amount of the sample.
Co-reporter:Jian Wang, Ying Sun, Liying Wang, Xiaonan Zhu, Hanqi Zhang, Daqian Song
Colloids and Surfaces B: Biointerfaces 2010 Volume 81(Issue 2) pp:600-606
Publication Date(Web):1 December 2010
DOI:10.1016/j.colsurfb.2010.08.007
In this paper, the core/shell Fe3O4/Au nanocomposites modified with 3-mercaptopropionic acid (MPA) were prepared and applied in the surface plasmon resonance (SPR) biosensor. And the detailed investigation of Fe3O4/Au nanocomposites was separately performed by UV–vis spectroscopy and transmission electronic microscopy. As the magnetic property and exceptional optical properties, the Fe3O4/Au nanocomposites were used as the solid support for the goat anti-human IgM, which could be immobilized on the surface of SPR biosensor chip by a magnetic pillar. This novel method of immobilizing goat anti-human IgM simplified experimental procedures and facilitated the regeneration of the sensing membrane. In addition, the different diameter of Fe3O4/Au nanocomposites could be obtained with the different amount of MPA in the solution. And the effect of Fe3O4/Au nanocomposites with different diameters on the sensitivity of SPR biosensor was also explored. As a result, the SPR biosensor exhibits a satisfactory response for human IgM in the concentration range of 0.30–20.00 μg ml−1 and the increasing nanocomposite diameter is in favor of the sensitivity enhancement of SPR biosensor.
Co-reporter:Jian Wang, Liying Wang, Ying Sun, Xiaonan Zhu, Yanbo Cao, Xinghua Wang, Hanqi Zhang, Daqian Song
Colloids and Surfaces B: Biointerfaces 2010 Volume 75(Issue 2) pp:520-525
Publication Date(Web):1 February 2010
DOI:10.1016/j.colsurfb.2009.09.029
A novel surface plasmon resonance (SPR) biosensor for the determination of human IgG was introduced. The biosensor was prepared with three layers of titania sol–gel membrane by vapor deposition. The colloid Au nanoparticle (AuNP) was immobilized in the second layer of titania membrane and the AuNP coupled with rabbit anti-human IgG was encapsulated in the third layer. The AuNP in the second layer of titania membrane was proved to be effective in the sensitivity enhancement of SPR biosensor. The lowest concentration that could be detected obtained by the biosensor with AuNP is about eight times lower than that obtained without AuNP. In addition, the titania sol–gel is a porous homogeneous material that permits analytes to access the encapsulated biomolecule and can provide a controlled environment for the study of biomolecular recognition. The titania sol–gel was also confirmed to be benefit for biomolecule to keep bioactivity, which could offer a good waterish microenvironment. As a result, the modified biosensor exhibits a satisfactory response for human IgG in the concentration range of 0.30–40.00 μg mL−1 and shows favorable bioactivity for a long time.
Co-reporter:Liying Wang, Jian Wang, Songling Zhang, Ying Sun, Xiaonan Zhu, Yanbo Cao, Xinghua Wang, Hanqi Zhang, Daqian Song
Analytica Chimica Acta 2009 Volume 653(Issue 1) pp:109-115
Publication Date(Web):19 October 2009
DOI:10.1016/j.aca.2009.09.001
A wavelength modulation surface plasmon resonance biosensor based on ZnO–Au nanocomposites for the detection of human IgM was developed. Self-assembly technique has the advantages of flexibility, simplicity and the precise control of film component and was applied to the building of the sensor. The ZnO–Au nanocomposites are in a dumbbell-like shape and can be immobilized on the Au film through 1,6-hexanedithiol by covalent attachment. Meanwhile the activated ZnO nanocrystals can be used to connect protein. The biosensor based on ZnO–Au nanocomposites was used to detect human IgM. Some experimental conditions were examined and optimized. In the selected conditions, the modified biosensor exhibits a satisfactory response for human IgM in the concentration range of 0.30–20.00 μg mL−1. However, the biosensor without ZnO–Au nanocomposites shows a response for human IgM in the concentration range of 1.25–20.00 μg mL−1. Compared with the biosensor based on Au film, when the biosensor based on the ZnO–Au nanocomposites was applied, the sensitivity for determination of human IgM is significantly enhanced.
Co-reporter:
Analytical Methods (2009-Present) 2013 - vol. 5(Issue 16) pp:NaN4118-4118
Publication Date(Web):2013/06/13
DOI:10.1039/C3AY40638E
A practical, simple and rapid method based on matrix solid phase dispersion (MSPD) extraction and ultrafast liquid chromatography (UFLC) was developed and validated for the simultaneous isolation, purification and quantification of geniposide from the fruit of Gardenia jasminoides Ellis. The experimental parameters such as the type of dispersing sorbent and elution solvent, the volume of elution solvent, the ratio of sorbent/sample and the particle size of sample were first studied separately by a univariate method. Then relevant parameters were evaluated by orthogonal screening to determine the optimal operation conditions. The optimal conditions were 0.5 g of fruit of Gardenia jasminoides Ellis, 0.75 g of Celite (diatomaceous earth) as dispersing sorbent and a volume of 25 mL of aqueous solutions containing 70% methanol as the elution solvent. The feasibility of the method was evaluated by investigating linearity, accuracy, precision, real sample analysis, limit of detection (LOD) and limit of quantification (LOQ). The LOD and LOQ were 0.026 and 0.087 μg mL−1, respectively. The recoveries ranged from 87.9% to 104.8% at two spiking levels with relative deviations (RSDs) ranging from 0.6% to 3.9%. Compared with the conventional extraction methods, such as ultrasound-assisted extraction (UAE) and Soxhlet extraction (SE), the proposed method is quicker and more effective.
Co-reporter:
Analytical Methods (2009-Present) 2012 - vol. 4(Issue 7) pp:
Publication Date(Web):
DOI:10.1039/C2AY25056J
A vortex-assisted ionic liquid microextraction method coupled with ultra fast liquid chromatographic separation and detection was developed for the analysis of three aromatic amines, 4-chloroaniline, 1-naphthylamine and 4-aminobiphenyl, in environmental water samples. 1-Hexyl-3-methylimidazolium hexafluorophosphate [C6MIM][PF6] was used as the extraction solvent as it can disperse in water completely and quickly with the aid of vortex mixing. A dispersive solvent was not required. Several parameters such as type and volume of extraction solvent, vortex velocity, extraction time, centrifugation time, pH of sample solution and ionic strength in sample solution were investigated. Under the optimized conditions, the intra-day and inter-day precision of the proposed method were 2.3–3.5% (n = 5) and 2.8–5.3% (n = 5), respectively. The limits of detection and quantification were in the range of 0.24–0.57 μg L−1 and 0.80–1.90 μg L−1, respectively. The proposed method was applied in the determination of three aromatic amines in several real water samples. Acceptable recoveries of the analytes, ranging from 79% to 111% (the relative standard deviations ≤6.0%), were obtained.
Co-reporter:
Analytical Methods (2009-Present) 2013 - vol. 5(Issue 6) pp:
Publication Date(Web):
DOI:10.1039/C3AY26357F
The magnetic mesoporous microsphere-based extraction method coupled with ultra fast liquid chromatography (UFLC) was applied for the extraction and determination of Sudan dyes in environmental water samples. Fe3O4@SiO2 microspheres consisting of a Fe3O4 particle core and an ordered mesoporous silica shell were used. The Fe3O4 particles were prepared simply by a solvothermal reduction method. The mesoporous silica was prepared and coated on the Fe3O4 particles via a surfactant-templating approach by stirring at room temperature. The obtained Fe3O4@SiO2 microspheres possess superparamagnetism and a good mesoporous structure. The experimental parameters, including the amount of Fe3O4@SiO2 microspheres, the pH value of sample solution, extraction time, separation time, elution solvent, volume of elution solvent and elution time, were optimized. Under the optimized conditions, Fe3O4@SiO2 microspheres were successfully used to extract Sudan dyes in the environmental water samples and the enrichment factor is 500-fold. The result showed that the method had good linearity (r = 0.990–0.997), and the limits of detection (LODs) were from 0.082 to 0.12 ng ml−1. Recoveries obtained by analyzing the five spiked water samples were in the range of 87.10–111.4% and the intra-day and inter-day relative standard deviations (RSDs) were between 0.590 and 7.94%. The results indicated that the novel method could be applied successfully for the determination of Sudan dyes in environmental water samples.
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