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zwitterionic polymer

Caihong Liu, Jongho Lee, Jun Ma, Menachem Elimelech
In this study, we demonstrate a highly antifouling thin-film-composite (TFC) membrane by grafting a zwitterionic polymer brush via atom-transfer radical-polymerization (ATRP), a controlled, environmentally benign chemical process. Initiator molecules for polymerization were immobilized on the membrane surface by bio-inspired catechol chemistry, leading to the grafting of a dense zwitterionic polymer brush layer. Surface characterization revealed that the modified membrane exhibits reduced surface roughness, enhanced hydrophilicity, and lower surface charge...
January 17, 2017: Environmental Science & Technology
Chao Zhang, Hao-Nan Li, Yong Du, Meng-Qi Ma, Zhi-Kang Xu
The mussel-inspired polydopamine (PDA) coatings have been broadly exploited for constructing functional membrane surfaces. One-step co-deposition of PDA with antifouling polymers, especially zwitterionic polymer, has been regarded as a promising strategy for fabricating antifouling membrane surfaces. However, one challenge is that the co-deposition is usually a slow process with ten hours or even several days. Herein, we report that CuSO4/H2O2 is able to notably accelerate the co-deposition process of PDA with poly(sulfobetaine methacrylate) (PSBMA)...
January 16, 2017: Langmuir: the ACS Journal of Surfaces and Colloids
Natalia Wilkosz, Sami Rissanen, Małgorzata Cyza, Renata Szybka, Maria Nowakowska, Alex Bunker, Tomasz Róg, Mariusz Kepczynski
Uptake of piroxicam, a non-steroidal anti-inflammatory drug, from the intestines after oral intake is limited due to its low solubility and its wide use is associated with several side effects related to the gastrointestinal tract. In this study, all-atom molecular dynamics (MD) simulations and fluorescent spectroscopy were employed to investigate the interaction of piroxicam in neutral, zwitterionic, and cationic forms with lipid bilayers composed of phosphatidylcholine, cholesterol, and PEGylated lipids. Our study was aimed to assess the potential for encapsulation of piroxicam in liposomal carriers and to shed more light on the process of gastrointestinal tract injury by the drug...
January 10, 2017: European Journal of Pharmaceutical Sciences
Emma M Pelegri-O'Day, Samantha J Paluck, Heather D Maynard
Many proteins, especially those used as therapeutics, are unstable to storage and shipping temperatures, leading to increased costs in research and industry. Therefore, the design and synthesis of novel stabilizers is an important area of investigation. Herein we report new degradable polymers that stabilize proteins to environmental stressors such as refrigeration and elevated temperature. Specifically, polycaprolactones with different pendant groups were synthesized and surveyed for their ability to stabilize an important therapeutic protein to storage and shipping conditions...
January 12, 2017: Journal of the American Chemical Society
Yang Hu, Yang Li, Fu-Jian Xu
Because of their biocompatibility, biodegradability, and unique bioactive properties, polysaccharides have been recognized and directly applied as excellent candidates for various biomedical applications. In order to introduce more functionalities onto polysaccharides, various modification methods were applied to improve the physical-chemical and biochemical properties. Grafting polysaccharides with functional polymers with limited reaction sites maximizes the structural integrity. To the best of our knowledge, great efforts have been made by scientists across the world, including our research group, to explore different strategies for the synthesis and design of controllable polymer-grafted polysaccharides...
January 9, 2017: Accounts of Chemical Research
Shrinivas Venkataraman, Jeremy P K Tan, Victor W L Ng, Eddy W P Tan, James L Hedrick, Yi Yan Yang
Introduction of hydrophilic components, particularly amines and zwitterions, onto a degradable polymer platform, while maintaining precise control over the polymer composition, has been a challenge. Recognizing the importance of these hydrophilic residues in multiple aspects of the nanobiomedicine field, herein, a straightforward synthetic route to access well-defined amphiphilic and hydrophilic degradable block copolymers from diethanolamine-derived functional eight-membered N-substituted aliphatic cyclic carbonates is reported...
January 9, 2017: Biomacromolecules
Yuhang Zhou, Junjie Li, Ying Zhang, Dianyu Dong, Ershuai Zhang, Feng Ji, Zhihui Qin, Jun Yang, Fanglian Yao
The prediction of the diffusion coefficient of solute, especially bioactive molecules, in hydrogel is significant in biomedical field. Considering the randomness of solute movement in hydrogel network, a physical diffusion RMP-1 model based on obstruction theory was established in this study. Based on this, the physical properties of the solute and polymer chain and the interactions between them were introduced into this model, RMP-2 and RMP-3 model were established to understand and predict the diffusion behaviors of proteins in hydrogel...
January 6, 2017: Journal of Physical Chemistry. B
Yuemei Han, Xu Xu, Junmei Tang, Chenghui Shen, Quankui Lin, Hao Chen
Intraocular lens (IOL) is an efficient implantable device commonly used for treating cataracts. However, bioadhesion of bacteria or residual lens epithelial cells on the IOL surface after surgery causes postoperative complications, such as endophthalmitis or posterior capsular opacification, and leads to loss of sight again. In the present study, zwitterionic polymer brushes were fabricated on the IOL surface via bottom-up grafting procedure. The attenuated total reflection-Fourier transform infrared and contact angle measurements indicated successful surface modification, as well as excellent hydrophilicity...
2017: International Journal of Nanomedicine
Yiman Zhao, Yajing Chen, Zhichao Xiong, Xudong Sun, Quanqing Zhang, Yangyang Gan, Lingyi Zhang, Weibing Zhang
In consideration of the close connection between glycopeptides and human diseases, the efficient method to separate and enrich glycopeptides from complex biological samples is urgently required. In the work, we developed a magnetic zwitterionic-hydrophilic material for highly effective separation and analysis of glycopeptides from complex samples. The Fe3O4 particles were covered with a thick layer of polymer by one-step reflux-precipitation polymerization (RPP), subsequently decorated by Au nanoparticles (Au NPs) through in situ reduction and finally modified with zwitterionic groups...
December 19, 2016: Journal of Chromatography. A
Constain H Salamanca, Duvan F Castillo, Juan D Villada, Gustavo R Rivera
Biocompatible polymeric materials with the potential to form functional structures, in association with different therapeutic molecules, in physiological media, represent a great potential for biological and pharmaceutical applications. Therefore, here the formation of a nano-complex between a synthetic cationic polymer and model drug (ampicillin trihydrate) was studied. The formed complex was characterized by size and zeta potential measurements, using dynamic light scattering and capillary electrophoresis...
March 1, 2017: Materials Science & Engineering. C, Materials for Biological Applications
Yuji Pu, Zheng Hou, Mya Mya Khin, Rubi Zamudio-Vázquez, Kar Lai Poon, Hongwei Duan, Mary B Chan-Park
Cationic polymethacrylates are interesting candidates for bacterial disinfectants since they can be made in large-scale by various well-established polymerization techniques such as atom transfer radical polymerization (ATRP). However, they are usually toxic or ineffective in serum and various strategies to improve their biocompatibility or nonfouling property have often resulted in compromised bactericidal activity. Also, star-shaped polymers are less explored than linear polymers for application as antibacterial compounds...
December 23, 2016: Biomacromolecules
Ashraf Saad Rasheed, Bashaer Abbas Al-Phalahy, Andreas Seubert
Zwitterionic stationary phases with nearly identical capacities were prepared by graft polymerization of a series of sulfobetaine precursors onto the surface of porous PS/DVB particles. The different spacer lengths are used as an investigative tool for the retention behavior of carboxylic acids; namely malonic, succinic, glutaric and maleic acid. In zwitterionic ion chromatography-hydrophilic interaction liquid chromatography (ZIC-HILIC) separation mode, the retention characteristic of carboxylic acids was examined using sodium acetate/acetonitrile eluents and UV detection...
January 2017: Journal of Chromatographic Science
Taeseung Yang, Sang Koo Choi, Daehwan Park, Yea Ram Lee, Chan Bok Chung, Jin Woong Kim
This study introduces a new type of associative nanoparticle (ANP) that provides controlled chain-to-chain attraction with an associative polymer rheology modifier (APRM) to produce highly stable Pickering emulsions. The ANPs were synthesized by grafting hydrophobically modified hygroscopic zwitterionic poly(2-methacryloyloxyethyl phosphorylcholine-co-stearyl methacrylate) brushes onto 20 nm sized silica NPs via surface-mediated living radical polymerization. The ANP-stabilized Pickering emulsions show significant viscosity enhancement in the presence of the APRM...
December 20, 2016: Langmuir: the ACS Journal of Surfaces and Colloids
Nan Wang, Xin Jin, Dongbo Guo, Gangsheng Tong, Xinyuan Zhu
Iron accumulation in substantia nigra pars compacta (SNpc) has been proved to be a prominent pathophysiological feature of Parkinson's diseases (PD), which can induce the death of dopaminergic (DA) neurons, up-regulation of reactive oxygen species (ROS), and further loss of motor control. In recent years, iron chelation therapy has been demonstrated to be an effective treatment for PD, which has shown significant improvements in clinical trials. However, the current iron chelators are suboptimal due to their short circulation time, side effects, and lack of proper protection from chelation with ions in blood circulation...
December 29, 2016: Biomacromolecules
Khoerunnisa, Zihnil A I Mazrad, Insik In, Sung Young Park
A zwitterionic fluorescent polymer with high sensitivity to pH changes was constructed for the detection and imaging of both gram-positive and gram-negative pathogenic bacteria. A detection probe using the zwitterionic fluorescent polymer was synthesized with single boron dipyrromethane (BODIPY) as a hydrophobic dye and bromoethane as a cationic group for bacteria binding with conjugated poly(sulfobetaine methacrylate) (BOD/BE-PSM). The zwitterionic fluorescent polymer bound to bacteria through ionic complexes between anionic groups on the bacterial surface and cationic BOD/BE-PSM groups after 1h incubation...
April 15, 2017: Biosensors & Bioelectronics
Caihong Liu, Andreia F Faria, Jun Ma, Menachem Elimelech
We demonstrate the functionalization of thin-film composite membranes with zwitterionic polymers and silver nanoparticles (AgNPs) for combating biofouling. Combining hydrophilic zwitterionic polymer brushes and biocidal AgNPs endows the membrane with dual functionality: antiadhesion and bacterial inactivation. An atom transfer radical polymerization (ATRP) reaction is used to graft zwitterionic poly(sulfobetaine methacrylate) (PSBMA) brushes to the membrane surface, while AgNPs are synthesized in situ through chemical reduction of silver...
January 3, 2017: Environmental Science & Technology
Volkan Yesilyurt, Omid Veiseh, Joshua C Doloff, Jie Li, Suman Bose, Xi Xie, Andrew R Bader, Michael Chen, Matthew J Webber, Arturo J Vegas, Robert Langer, Daniel G Anderson
The surface modification of implantable biomaterials with zwitterionic phosphorylcholine polymer is demonstrated through mussel-mimetic catecholamine polymer thin films. Using this method, the surfaces of alginate hydrogel microspheres and polystyrene microbeads, a model material known to produce robust foreign body responses and fibrosis, are successfully modified to reduce the tissue reaction by reducing the fibrosis in immunocompetent C57BL/6J mice.
December 15, 2016: Advanced Healthcare Materials
G D Bothun, N Ganji, I A Khan, A Xi, C Bobba
We have examined the interactions between polymer-coated anionic (Ag-COOH) and cationic (Ag-NH) silver nanoparticles, and net-anionic lipid monolayers using dynamic surface pressure measurements. Monolayers composed of saturated or monounsaturated mixtures of anionic phosphatidylglycerol (PG) and zwitterionic phosphatidylcholine (PC) lipids (3:1 molar ratio) were used to determine how lipid packing and monolayer phase state influence the extent of nanoparticle binding and the monolayer response. Anionic Ag-COOH inserted into saturated dipalmitoyl-PC/PG (DPPC/DPPG) and dioleoyl-PC/PG (DOPC/DOPG) monolayers at a low initial surface pressure (10 mN m(-1)) and caused lipid condensation at high initial surface pressures (20 and 30 mN m(-1))...
December 30, 2016: Langmuir: the ACS Journal of Surfaces and Colloids
Yong Zhong, Lihong Huang, Zhisen Zhang, Yunjing Xiong, Liping Sun, Jian Weng
Graphene oxides (GOs) with different surface characteristics, such as size, reduction degree and charge, are prepared, and their effects on the specificity of polymerase chain reaction (PCR) are investigated. In this study, we demonstrate that GO with a large size and high reduction degree is superior to small and nonreduced GO in enhancing the specificity of PCR. Negatively charged polyacrylic acid (PAA), positively charged polyacrylamide (PAM), neutral polyethylene glycol (PEG) and zwitterionic polymer poly(sulfobetaine) (pSB) are used to modify GO...
2016: International Journal of Nanomedicine
Iman Adipurnama, Ming-Chien Yang, Tomasz Ciach, Beata Butruk-Raszeja
Cardiovascular implants, especially vascular grafts made of synthetic polymers, find wide clinical applications in the treatment of cardiovascular diseases. However, cases of failure still exist, notably caused by restenosis and thrombus formation. Aiming to solve these problems, various approaches to surface modification of synthetic vascular grafts have been used to improve both the hemocompatibility and long-term patency of artificial vascular grafts. Surface modification using hydrophilic molecules can enhance hemocompatibility, but this may limit the initial vascular endothelial cell adhesion...
December 20, 2016: Biomaterials Science
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