A method was developed to modify silicon surfaces with good protein resistance and specific cell attachment. A silicon surface was initially deposited using a block copolymer of N-vinylpyrrolidone （NVP） and 2-hydrox...
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A method was developed to modify silicon surfaces with good protein resistance and specific cell attachment. A silicon surface was initially deposited using a block copolymer of N-vinylpyrrolidone （NVP） and 2-hydroxyethyl methacrylate （HEMA） （PVP-b-PHEMA） film through surface-initiated atom transfer radical polymerization and then further immobilized using a short arginine-glycine-aspartate （RGD） peptide. Our results demonstrate that the RGD-modified surfaces （Si-RGD） can suppress non-specific adsorption of proteins and induce the adhesion of L929 cells. The Si-RGD surface exhibited higher cell proliferation rates than the unmodified silicon surface. This research established a simple method for the fabrication of dual-functional silicon surface that combines antifouling and cell attachment promotion.
Two pH-responsive amphiphilic diblock copolymers, namely polyisobutylene-block-poly[2-（N,N- dimethylamino）ethyl methaerylate] （PIB-b-PDMAEMA） and polyisobutylene-block-poly（metharylic acid） （PIB-b-PMAA）, were ...
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Two pH-responsive amphiphilic diblock copolymers, namely polyisobutylene-block-poly[2-（N,N- dimethylamino）ethyl methaerylate] （PIB-b-PDMAEMA） and polyisobutylene-block-poly（metharylic acid） （PIB-b-PMAA）, were synthesized via oxyanion-initiated polymerization, and their multiple self-assembly behaviors have been studied. An exo-01efin-terminated highly reactive polyisobutylene （HRPIB） was first changed to hydroxyl-terminated PIB （PIB-OH） via hydroboration-oxidation of C =C double bond in the chain end, and then reacted with KH to yield a potassium alcoholate of PIB （PIB-O-K＋）. PIB-O-K＋ was immediately used as a macroinitiator to polymerize DMAEMA monomer, resulting in a cationic diblock copolymer PIB-b-PDMAEMA. With the similar synthesis procedure, the anionic diblock copolymer PIB-b- PMAA could be prepared via a combination of oxyanion-initiated polymerization of tert-butyl methacrylate （tBMA） and subsequent hydrolysis of tert-butyl ester groups in PtBMA block. The functional PIB and block copolymers have been fully characterized by 1H-NMR, FT-IR spectroscopy, and gel permeation chromatography （GPC）. These samples allowed us to systematically investigate the effects of block composition on the pH responsivity and various self-assembled morphologies of the copolymers in THF/water mixed solvent. Transmission electron microscopy （TEM） images revealed that these diblock copolymers containing small amount of original PIB without exo-olefin-terminated group are able to self-assemble into micelles, vesicles with different particle sizes and cylindrical aggregates, depending on various factors including block copolymer composition, solvent polarity and pH value.
The clinical success of many chemotherapeutics and biotherapeutics intimately depends on the development of non-toxic and efficient tumor-targeting nano-carrier *** ideal drug and protein carriers should be able to re...
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The clinical success of many chemotherapeutics and biotherapeutics intimately depends on the development of non-toxic and efficient tumor-targeting nano-carrier *** ideal drug and protein carriers should be able to retain and protect the payloads under extracellular settings(*** cell culture and during circulation) while dump them once arriving at the site of *** site-selective drug and protein release might on one hand maximize therapeutic effects and on the other hand minimize systemic side ***,despite significant progress has been made
Fullerene‐based liquid crystalline materials have both the excellent optical and electrical properties of fullerene and the self‐organization and external‐field‐responsive properties of liquid crystals (LCs). Here...
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Fullerene‐based liquid crystalline materials have both the excellent optical and electrical properties of fullerene and the self‐organization and external‐field‐responsive properties of liquid crystals (LCs). Herein, we demonstrate a new family of thermotropic [60]fullerene supramolecular LCs with hierarchical structures. The [60]fullerene dyads undergo self‐organization driven by π–π interactions to form triple‐layer two‐dimensional (2D) fullerene crystals sandwiched between layers of alkyl chains. The lamellar packing of 2D crystals gives rise to the formation of supramolecular LCs. This design strategy should be applicable to other molecules and lead to an enlarged family of 2D crystals and supramolecular liquid crystals.
The purpose of this research is to investigate the effects of the variously sulfated chitosans on lysozyme activity and structure. It was shown that the specific enzymatic activity of lysozyme remained almost similar ...
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The purpose of this research is to investigate the effects of the variously sulfated chitosans on lysozyme activity and structure. It was shown that the specific enzymatic activity of lysozyme remained almost similar to the native protein after being bound to 6-O-sulfated chitosan （6S-chitosan） and 3,6-O-sulfated chitosan （3,6S-chitosan）, but decreased greatly after being bound to 2-N-6-O-sulfated chitosan （2,6S-chitosan）. Meanwhile, among these sulfated chitosans, 2,6S-chitosan induced the greatest conformational change in lysozyme as indicated by the fluorescence spectra. These findings demonstrated that when sulfated chitosans of different structures bind to lysozyme, lysozyme undergoes conformational change of different magnitudes, which results in corresponding levels of lysozyme activity. Further study on the interaction of sulfated chitosans with lysozyme by surface plasmon resonance （SPR） suggested that their affinities might be determined by their molecular structures.
Recent developments in polymer-based controlled delivery systems have made a significant clinical impact. The second Symposium on Innovative polymers for Controlled Delivery (SIPCD) was held in Suzhou, China to addres...
Recent developments in polymer-based controlled delivery systems have made a significant clinical impact. The second Symposium on Innovative polymers for Controlled Delivery (SIPCD) was held in Suzhou, China to address the key challenges and provide up-to-date progress and future perspectives in the innovation of polymer-based therapeutics. At SIPCD, a stimulating panel discussion was introduced for the first time on “What is the future of nanomedicine?” This report highlights the most recent research and developments in biomedical polymers and nanomedicine made by 29 invited scientists from around the world, as well as important issues regarding clinical advancements of nanomedicine conferred during the panel discussion.
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