Co-reporter:Jing Xu, Xiangyi Li, Xiaodong Li, Bao Li, Lixin Wu, Wen Li, Xiaoming Xie, and Rong Xue
Biomacromolecules November 13, 2017 Volume 18(Issue 11) pp:3524-3524
Publication Date(Web):September 7, 2017
DOI:10.1021/acs.biomac.7b00817
Peptide assembly has reached exquisite levels of efficiency in the creation of bioactive materials. However, we have not yet been able to take what we have learned from peptide assembly to develop a general strategy for the fabrication of biomimetic underwater adhesives, which retain significant advantages as medical glue for clinical treatment. Herein we report a simple approach to prepare peptide-based adhesives through the supramolecular polymerization of cationic peptides drove by polyoxometalates (PMs). Mass spectra, Fourier-transform infrared spectra and 183W NMR spectra confirmed the structural integrity of peptides and PMs during the coassembly process. Scanning electron microscopy demonstrated that the multivalent interactions between peptides and polyoxometaltes led to the formation of robust 3D network structures. The rheological study revealed that the peptide/PM assemblies exhibited mechanically rigid gel-like behavior and self-healing property. Interestingly, the assemblies showed the capacity to adhere various wet solid materials under waterline. The shear strength of the peptide-based adhesives are stronger than that of the commercially available fibrin glue. This finding is exciting and serves to expand our capability of the fabrication of peptide-based materials.
Co-reporter:Jing Xu;Xiaodong Li;Jingfang Li;Xiangyi Li; Bao Li;Yang Wang; Lixin Wu; Wen Li
Angewandte Chemie International Edition 2017 Volume 56(Issue 30) pp:8731-8735
Publication Date(Web):2017/07/17
DOI:10.1002/anie.201703774
AbstractSessile organisms have undergone long-term evolution to develop the unique ability by positioning themselves on wet solid surface through secreting adhesive proteins. The present study reveals that natural amino acid monomers can also exhibit similar adhesion capacity. This kind of biomimetic adhesives were created by the one-step aqueous assembly of basic amino acids with assistance of anionic polyoxometalates. The polyoxometalates not only serve as multivalent scaffold to initiate the supramolecular cross-linking of amino acid molecules, but also function as a redox component, bestowing the wet adhesives with electrochromic features.
Co-reporter:Jing Xu;Xiaodong Li;Jingfang Li;Xiangyi Li; Bao Li;Yang Wang; Lixin Wu; Wen Li
Angewandte Chemie 2017 Volume 129(Issue 30) pp:8857-8861
Publication Date(Web):2017/07/17
DOI:10.1002/ange.201703774
AbstractSessile organisms have undergone long-term evolution to develop the unique ability by positioning themselves on wet solid surface through secreting adhesive proteins. The present study reveals that natural amino acid monomers can also exhibit similar adhesion capacity. This kind of biomimetic adhesives were created by the one-step aqueous assembly of basic amino acids with assistance of anionic polyoxometalates. The polyoxometalates not only serve as multivalent scaffold to initiate the supramolecular cross-linking of amino acid molecules, but also function as a redox component, bestowing the wet adhesives with electrochromic features.
Co-reporter:Jingfang Li, Jing Xu, Xiaodong Li, Wenmei Gao, Liyan Wang, Lixin Wu, Myongsoo Lee and Wen Li
Soft Matter 2016 vol. 12(Issue 25) pp:5572-5580
Publication Date(Web):19 May 2016
DOI:10.1039/C6SM00752J
A series of cationic peptides with alternating lysines and hydrophobic residues were designed and synthesized. These kinds of short peptides with protonated lysines can complex with anionic heteropoly acids (HPAs) to form a stable gel in water/ethanol mixed solution. Circular dichroism spectroscopy showed that the short peptides adopted a mixed conformation (β-sheet and random-coil) within the gel matrix. Scanning and transmission electron microscopy revealed that the heteropoly acids, acting as nanosized cross-linkers, first initiated the self-assembly of the cationic peptides into spherical nanostructures. Then these nanospheres accumulated with each other through hydrogen bonds and hydrophobic interactions to form large sheet-like assemblies, which further interconnected with each other forming continuous 3D network structures. Fourier-transform infrared spectroscopy showed that the structural integrity of the HPAs was maintained during the gelation process. The resultant hybrid gels showed reversible photo- and elecrtro-chromic properties. X-ray photoelectron spectroscopy revealed that the hybrid gels, capable of persistent and reversible changes of their colour, are attributed to the intervalence charge-transfer transition of the HPAs. Reversible information writing and erasing were demonstrated through a repeated photo-lithograph or electric stimuli without significant loss of the gel performance.
Co-reporter:Jingfang Li;Zhijun Chen;Mengcheng Zhou;Jiangbo Jing; Wen Li;Yang Wang; Lixin Wu;Liyan Wang;Yanqiu Wang ; Myongsoo Lee
Angewandte Chemie International Edition 2016 Volume 55( Issue 7) pp:2592-2595
Publication Date(Web):
DOI:10.1002/anie.201511276
Abstract
Multivalent peptide nanofibers have attracted intense attention as promising platforms, but the fabrication of those nanofibers is mainly dependent on the spontaneous assembly of β-sheet peptides. Herein we report an alternative approach to the creation of nanofibers: the polyoxometalate-driven self-assembly of short peptides. The resultant nanofibers with concentrated positive charges are excellent multivalent ligands for binding with bacterial cells and thus lead to a salient improvement in bioactivity.
Co-reporter:Jingfang Li;Zhijun Chen;Mengcheng Zhou;Jiangbo Jing; Wen Li;Yang Wang; Lixin Wu;Liyan Wang;Yanqiu Wang ; Myongsoo Lee
Angewandte Chemie 2016 Volume 128( Issue 7) pp:2638-2641
Publication Date(Web):
DOI:10.1002/ange.201511276
Abstract
Multivalent peptide nanofibers have attracted intense attention as promising platforms, but the fabrication of those nanofibers is mainly dependent on the spontaneous assembly of β-sheet peptides. Herein we report an alternative approach to the creation of nanofibers: the polyoxometalate-driven self-assembly of short peptides. The resultant nanofibers with concentrated positive charges are excellent multivalent ligands for binding with bacterial cells and thus lead to a salient improvement in bioactivity.
Co-reporter:Wen Li, Yongju Kim, Jingfang Li and Myongsoo Lee
Soft Matter 2014 vol. 10(Issue 29) pp:5231-5242
Publication Date(Web):04 Jun 2014
DOI:10.1039/C4SM01068J
The construction of supramolecular polymers has been intensively pursued because the nanostructures formed through weak non-covalent interactions can be triggered by external stimuli leading to smart materials and sensors. Self-assemblies of coordination polymers consisting of metal ions and organic ligands in aqueous solution also provide particular contributions in this area. The main motivation for developing those coordination polymers originates from the value-added combination between metal ions and ligands. This review highlights the recent progress of the dynamic self-assembly of coordination polymers that result from the sophisticated molecular design, towards fabricating stimuli-responsive systems and bio-related materials. Dynamic structural changes and switchable physical properties triggered by various stimuli are summarized. Finally, the outlook for aqueous nanostructures originated from the dynamic self-assembly of coordination polymers is also presented.
Co-reporter:Jingfang Li, Xiaopeng Ou, Savannah Sims, Wen Li and Lixin Wu
RSC Advances 2014 vol. 4(Issue 100) pp:56998-57008
Publication Date(Web):27 Oct 2014
DOI:10.1039/C4RA12174K
A quaternary ammonium surfactant (S) carrying a phenol terminal was grafted on the surface of nano-sized polyoxometalates, H4SiW12O40 (PM-1), K6P2W18O62 (PM-2) and Na10[Co4(H2O)2(VW9O34)2] (PM-3), respectively, by ionic self-assembly. The obtained complexes were connected with the poly(vinylpyridine) (P4VP) backbone via hydrogen bonds, resulting in the formation of nano-hybrid supramolecular polymers. Differential scanning calorimetry, polarized light microscopy, temperature-dependent X-ray diffraction, and transmission electron microscopy confirmed that the hybrid polymers containing PM-1 exhibited a thermotropic smectic C phase, where the alkyl chains of the surfactant are equally distributed on either side of PM-1 in a compact manner with only interfacial hydrogen bonding interactions between the phenol groups and the pyridine units of P4VP. Detailed investigation revealed that the liquid crystal properties are dependent on the molar ratio between PM-1 and P4VP, the molecular weight of P4VP and the charges of PMs. An increase of charge from 4 to 6 results in a loss of liquid crystal behaviour. Although the liquid crystal structure of the hybrid polymers is independent of the molecular weight of the P4VP backbone, the transition temperatures are strongly related to the change of the molecular weight of P4VP. The UV-vis and XPS measurements reveal that these hybrid liquid crystal polymers show reversible photochromic properties because of the multi-electronic redox activity of PM-1. The present article opens up a door for developing nano-hybrid liquid crystal polymers via a multi-step supramolecular self-assembly strategy, and provide an insight into understanding the nature and mechanisms of the influence of nano-objects on the self-assembly behaviour of hybrid polymers.
Co-reporter:Yang Yang ; Bin Zhang ; Yizhan Wang ; Liang Yue ; Wen Li ;Lixin Wu
Journal of the American Chemical Society 2013 Volume 135(Issue 39) pp:14500-14503
Publication Date(Web):September 16, 2013
DOI:10.1021/ja4057882
A “smart” core–shell complex is designed to combine a catalytic reaction and automatic separation through remote light control. Here, we present the induced amphiphilic behavior of a surfactant-encapsulated polyoxometalate complex with photoresponsive azobenzene units on the periphery. The reversible phase transfer of the complex shuttle between two incompatible phase termini, driven by a photoisomerization-induced polarity change, further facilitates the separation and recycle of the catalyst.
Co-reporter:Wen Li, Yongju Kim and Myongsoo Lee
Nanoscale 2013 vol. 5(Issue 17) pp:7711-7723
Publication Date(Web):14 Jun 2013
DOI:10.1039/C3NR02574H
The construction of supramolecular nanoscopic architectures has been intensively pursued because of their unique features for applications in nanoscience and biomimetic chemistry. Molecular self-assemblies of aromatic rod–coil amphiphiles consisting of rigid rod segments and hydrophilic flexible chains in aqueous solution provide a facile avenue into this area. This feature article highlights the recent progress regarding the construction of aqueous assemblies that result from the sophisticated design of aromatic rod–coils, with the aim to develop stimuli-responsive systems and bioactive materials. Important factors affecting the self-assembly morphologies are discussed and summarized. Dynamic structural changes triggered by temperature and guest molecules are demonstrated. Finally, the perspective of bioactive nanostructures originated from self-assembly of aromatic block amphiphiles is also introduced.
Co-reporter:Wen Li, Jingfang Li and Myongsoo Lee
Chemical Communications 2013 vol. 49(Issue 74) pp:8238-8240
Publication Date(Web):17 Jul 2013
DOI:10.1039/C3CC44238A
Facial peptide P1 carrying repeating hydrophobic and hydrophilic residues as well as lysine terminals self-assemble into uniform toroid structures. The sensitive balance between the hydrophobic interactions and electrostatic repulsion dominates the formation of highly curved assemblies.
Co-reporter:Bao Li;Jing Zhang;Shan Wang, ;Lixin Wu
European Journal of Inorganic Chemistry 2013 Volume 2013( Issue 10-11) pp:
Publication Date(Web):
DOI:10.1002/ejic.201390043
Co-reporter:Bao Li;Jing Zhang;Shan Wang, ;Lixin Wu
European Journal of Inorganic Chemistry 2013 Volume 2013( Issue 10-11) pp:1869-1875
Publication Date(Web):
DOI:10.1002/ejic.201200983
Abstract
Three surfactant-encapsulated polyoxometalate (SEP) complexes were synthesized by grafting T-shaped quaternary ammonium units onto the surface of K5BW12O40, K6SiW11O39Co, and Na10[Mn4(H2O)2(VW9O34)2]·34H2O. All the complexes possess shell–core structures, in which the peripheral mesogenic units adopt a lateral attachment. The bulk organization of the complexes with thermal stimulus was studied by polarized optical microscopy, differential scanning calorimetry, and X-ray diffraction. The quaternary ammonium surfactant alone was found to form smectic structures, whereas the SEPs exhibited nematic characteristics. The detailed structural characterizations suggested the presence of a delicate synergy between the surfactants and polyoxometalates (POMs). The orientation of the mesogenic units was demonstrated to have a pivotal influence on the formation of liquid crystalline structures of the SEPs by comparison with the reported SEPs with head-to-tail attached mesogenic units. The clearing temperatures of the nematic complexes were found to be dependent on the number of peripheral surfactants. Finally, the magnetism of the polyoxometalates was proven to be well maintained in the liquid crystalline matrices, which allows the potential development of magnetically tunable liquid crystals bearing nematic structures.
Co-reporter:Mingjun Zhou, Jing Zhang, Shan Wang, Deanna Boyer, Huan Guo, Wen Li and Lixin Wu
Soft Matter 2012 vol. 8(Issue 30) pp:7945-7951
Publication Date(Web):02 Jul 2012
DOI:10.1039/C2SM25921D
A series of quaternary ammonium salts (1a–1e) with different lateral substitution groups in the middle part of the hydrophobic chains were designed and synthesized. Differential scanning calorimetry, polarized optical microscopy, and X-ray diffraction showed that compound 1a formed the smectic T phase at high temperature. Upon increasing the volume of the lateral groups in 1b, 1c and 1d, low melting point ILCs with smectic A phases were observed. However, the liquid crystalline structure was broken in compound 1e with large lateral groups. FT-IR measurements showed that the lateral groups resulted in an increase of the gauche conformation, which implies that the bulky effect of the lateral groups reduced the hydrophobic interactions and prevented close stacking. The phase behavior of compounds 2a–2c carrying an ethyl formate lateral group with various main chain lengths was also studied, and it was found that the clearing-point temperature is strongly dependent on the length of the hydrophobic chains. The rheological properties of the laterally substituted ILCs were further investigated. Typical shear thinning behavior was observed for all the ILCs, based on the shear rate-dependent viscosity curves. However, the viscosity vs. temperature curves showed that the laterally substituted ILCs exhibited biphasic interval behavior, which is different from the conventional ILCs, such as compounds 3a and 3b, where a drastic decrease was observed. The rheological behavior observed in this system is attributed to the slow kinetics caused by the laterally substituted molecular structure.
Co-reporter:Jing Zhang, Mingjun Zhou, Shan Wang, Jessica Carr, Wen Li, and Lixin Wu
Langmuir 2011 Volume 27(Issue 7) pp:4134-4141
Publication Date(Web):March 1, 2011
DOI:10.1021/la2000574
A series of quaternary ammonium amphiphiles (A-n) bearing carboxylic acid groups were designed and synthesized. The branched bolaform structures can be constructed by dimerizations of carboxylic acid groups through intermolecular hydrogen bonding, as demonstrated by the Fourier transform infrared (FT-IR) spectra and the temperature-dependent FT-IR spectra. The thermotropic organizations of branched bolaform ammonium dimer complexes were characterized by differential scanning calorimetry, polarized optical microscopy, and X-ray diffraction. We investigated the influence of the spacer between the cationic group and the benzene ring on the thermotropic organization. A-6 with short lateral alkyl chains formed a simple layered structure at room temperature and exhibited smectic A mesophase above 145 °C, whereas A-8 with intermediate lateral chain length organized into smectic A phase over a wide temperature range. A further increase of the length (n = 10, 12) of the lateral chains resulted in the formation of lamellar structure with in-plane layered periodicity, which is rare in the organization of ionic compounds. A packing model of the quasi-2D lamellar was proposed on the basis of the experimental data of X-ray diffraction results. Notably, the quasi-2D lamellar structure could evolve into a simple layer with the increase of temperature. The present results showed a direct relationship in which the branched architecture can be applied to tune the self-assembly behavior of ionic amphiphiles and is allowed to construct new layered superstructure.
Co-reporter:Wen Li, Jingfang Li and Myongsoo Lee
Chemical Communications 2013 - vol. 49(Issue 74) pp:NaN8240-8240
Publication Date(Web):2013/07/17
DOI:10.1039/C3CC44238A
Facial peptide P1 carrying repeating hydrophobic and hydrophilic residues as well as lysine terminals self-assemble into uniform toroid structures. The sensitive balance between the hydrophobic interactions and electrostatic repulsion dominates the formation of highly curved assemblies.
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