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zwitterionic polymer

Lifu Li, Tadashi Nakaji-Hirabayashi, Hiromi Kitano, Kohji Ohno, Yoshiyuki Saruwatari, Kazuyoshi Matsuoka
A mixed self-assembled monolayer (SAM) of an initiator (3-(2-bromo-2-isobutyryloxy)propyl triethoxysilane) for atom transfer radical polymerization (ATRP) and an agent (6-(triethoxysilyl)hexyl 2-(((methylthio)carbonothioyl)thio)-2-phenylacetate) for reversible addition-fragmentation chain transfer (RAFT) polymerization was constructed on the surface of a silicon wafer or glass plate by a silane coupling reaction. When a UV light at 254nm was irradiated at the mixed SAM through a photomask, the surface density of the bromine atom at the end of BPE in the irradiated region was drastically reduced by UV-driven scission of the BrC bond, as observed by X-ray photoelectron spectroscopy...
October 7, 2017: Colloids and Surfaces. B, Biointerfaces
Haotian Sun, Michael Yu Zarng Chang, Wei-I Cheng, Qing Wang, Alex Commisso, Meghan Capeling, Yun Wu, Chong Cheng
A fully biodegradable zwitterionic polymer and the corresponding conjugate with paclitaxel (PTX) were synthesized as promising biomaterials. Allyl-functionalized polylactide (PLA) was employed as the precursor of polymer backbones. UV-induced thiol-ene reaction was conducted to conjugate thiol-functionalized sulfobetaine (SB) with the PLA-based backbone. The resulting zwitterionic polymer did not exhibit considerable cytotoxicity. A polymer-drug conjugate was also obtained by thiol-ene reaction of both thiol-functionalized SB and PTX with allyl-functionalized PLA...
October 10, 2017: Acta Biomaterialia
Cristina Cepraga, Sophie Marotte, Edna Ben Daoud, Arnaud Favier, Pierre-Henri Lanoe, Cyrille Monnereau, Patrice Baldeck, Chantal Andraud, Jacqueline Marvel, Marie-Therese Charreyre, Yann Leverrier
One of the challenges of photodynamic therapy is to increase the penetration depth of light irradiation in the tumor tissues. Although two-photon excitation strategies have been developed, the two-photon absorption cross-sections of clinically used photosensitizers are generally low (below 300 GM). Besides, photosensitizers with high cross-section values are often non water-soluble. In this research work, a whole family of photosensitizer-polymer conjugates was synthesized via the covalent binding of a photosensitizer with a relatively high cross-section along a biocompatible copolymer chain...
October 11, 2017: Biomacromolecules
Lisa Adamiak, Mollie A Touve, Clare L M LeGuyader, Nathan C Gianneschi
Cellular uptake by macrophages and ensuing clearance by the mononuclear phagocyte system stands as a significant biological barrier for nanoparticle therapeutics. While there is a growing body of work investigating the design principles essential for imparting nanomaterials with long-circulating characteristics and macrophage evasion, there is still a widespread need for examining stimuli-responsive systems, particularly well-characterized soft materials, which differ in their physiochemical properties prior to and after an applied stimulus...
October 3, 2017: ACS Nano
Yi Xie, Litong Chen, Xiang Zhang, Shengqiu Chen, Man Zhang, Weifeng Zhao, Shudong Sun, Changsheng Zhao
Development of antibacterial membranes is strongly desired for biomedical applications. Herein, we integrated antifouling and bactericidal properties on polymeric membrane surface via Schiff-based layer-by-layer (LbL) assembly. Zwitterionic polymers bearing plentiful amino groups (based on polyethylenimine (PEI) and sulfobetaine methacrylate (SBMA), and termed as PEI-SBMA) were utilized to prepare an antifouling membrane surface; then robust wide-spectrum bactericidal Ag nanoparticles (Ag NPs) were in situ generated on the surface...
September 21, 2017: Journal of Colloid and Interface Science
Minghui Wang, Peter Kovacik, Karen K Gleason
Fouling has been a persistent issue within applications ranging from membrane separation to biomedical implantation. Research to date focuses on fouling-resistant coatings, where electrical conductivity is unnecessary. In this study, we report the synthesis of multifunctional thin films with both fouling resistance and electrical conductivity for their potential applications in the electrolysis-based self-cleaning of separation membranes and in the field of bioelectronics. This unique combination of properties results in multifunctional coatings that are a zwitterionic derivative of intrinsically conductive polymer poly(3,4-ethylenedioxythiophene) (PEDOT) synthesized via oxidative chemical vapor deposition (oCVD)...
September 29, 2017: Langmuir: the ACS Journal of Surfaces and Colloids
Wei Zhou, Wenpeng Zhang, Yikun Liu, Xinhong Yu, Zilin Chen
Capillary electrophoresis-mass spectrometry (CE-MS) is a hyphenated technique that combines the advantages like low sample consumption, high separation efficiency, short analytical time in CE and high sensitivity, powerful molecular structure elucidation in MS. Polyimide-coated fused silica capillary has become the most dominant capillary for CE, but it suffers from swelling and aminolysis of polyimide coating when treated with organic solvents and alkaline buffer in the CE-MS interface in which the polyimide coating at the end of the capillary is exposed to the solution, and this phenomenon can result in current instability, irregular electrospray and clogging at outlet after prolonged use...
September 22, 2017: Analytica Chimica Acta
Yu Wei, Jingxun Zhang, Xiantao Feng, Dongyin Liu
Zwitterionic copolymers keep good resistance to platelet adhesion and nonspecific protein adsorption. In this study, A block copolymer brushes consisting of carboxybetaine methacrylate (CBMA) and glycidyl methacrylate (GMA) were grafted from silicon wafers via surface-initiated atom transfer radical polymerization (SI-ATRP),and then the Arg-Glu-Asp-Val (REDV) peptide was attached to the polymer brush via an reactive epoxy group of the P(GMA) unit to improve endothelial cells (ECs) selectivity. These modified surfaces were evaluated with scanning electron microscopy (SEM), atomic force microscopy (AFM), attenuated total reflectance-Fourier transform infrared spectra (ATR-FTIR), X-ray photoelectron spectroscopy (XPS), and static water contact angle measurement (WCA)...
September 11, 2017: Journal of Biomaterials Science. Polymer Edition
Chun Y Wong, Hani Al-Salami, Crispin R Dass
Nanoparticles have demonstrated significant advancements in potential oral delivery of insulin. In this publication, we review the current status of polymeric, inorganic and solid-lipid nanoparticles designed for oral administration of insulin. Firstly, the structure and physiological function of insulin are examined. Then, the efficiency and shortcomings of insulin nanoparticle are discussed. These include the susceptibility to digestive enzyme degradation, instability in the acidic pH environment, poor mucus diffusion and inadequate permeation through the gastrointestinal epithelium...
October 28, 2017: Journal of Controlled Release: Official Journal of the Controlled Release Society
Ji Wang, Yujun Feng, Niti R Agrawal, Srinivasa R Raghavan
Wormlike micelles (WLMs) formed from surfactants have attracted much attention for their ability to thicken water in a manner similar to water-soluble polymers. It is known that WLMs are cylindrical filaments that can attain very long contour lengths (∼few μm), akin to chains of polymers with ultra-high molecular weights (UHMWs). In this study, we aim to make a direct comparison between the thickening capabilities of WLMs and UHMW polymers. The chosen surfactant is erucyl dimethyl amidopropyl betaine (EDAB), a C22-tailed zwitterionic surfactant known to form particularly long WLMs independent of salt...
September 20, 2017: Physical Chemistry Chemical Physics: PCCP
Brandon M Johnston, Cameron W Johnston, Rachel A Letteri, Tyler K Lytle, Charles E Sing, Todd Emrick, Sarah L Perry
Complex coacervation is a widely utilized technique for effecting phase separation, though predictive understanding of molecular-level details remains underdeveloped. Here, we couple coarse-grained Monte Carlo simulations with experimental efforts using a polypeptide-based model system to investigate how a comb-like architecture affects complex coacervation and coacervate stability. Specifically, the phase separation behavior of linear polycation-linear polyanion pairs was compared to that of comb polycation-linear polyanion and comb polycation-comb polyanion pairs...
September 20, 2017: Organic & Biomolecular Chemistry
Tong Xu, Jing Yang, Jiamin Zhang, Yingnan Zhu, Qingsi Li, Chao Pan, Lei Zhang
Electrospinning technology can easily produce different shaped fibrous structures, making them highly valuable to various biomedical applications. However, surface contamination of biomolecules, cells, or blood has emerged as a significant challenge to the success of electrospun devices, especially artificial blood vessels, catheters and wound dressings etc. Many efforts have been made to resist the surface non-specific biomolecules or cells adsorption, but most of them require complex pre-treatment processes, hard-to-remove metal catalysts or rigorous reaction conditions...
September 1, 2017: Biomedical Materials
Rachel A Letteri, Cristiam F Santa Chalarca, Ying Bai, Ryan C Hayward, Todd Emrick
Polymer zwitterions are generally regarded as hydrophilic and repellant or "slippery" materials. Here, a case is described in which the polymer zwitterion structure is tailored to decrease water solubility, stabilize emulsion droplets, and promote interdroplet adhesion. Harnessing the upper critical solution temperature of sulfonium- and ammonium-based polymer zwitterions in water, adhesive droplets are prepared by adding organic solvent to an aqueous polymer solution at elevated temperature, followed by agitation to induce emulsification...
August 21, 2017: Advanced Materials
Kai-Long Zhang, Jie Zhou, Hong Zhou, Ying Wu, Rui Liu, Li-Li Wang, Wei-Wen Lin, Guoming Huang, Huang-Hao Yang
The mononuclear phagocyte system (MPS) with key roles in recognition and clearance of foreign particles, is a major constraint to nanoparticle-based delivery systems. The desire to improve the delivery efficiency has prompted the search for stealthy long-circulating nanoplatforms. Herein, we design an antiphagocytic delivery system with "active" stealth behavior for cancer theranostics combining efficient MRI and enhanced drug delivery. We modify self-peptide, a synthetic peptide for active immunomodulation, to biodegradable poly(lactide-glycolide)-poly(ethylene glycol) (PLGA-PEG), then utilize the self-assembly properties of PLGA-PEG to form nanomicelles that encapsulating iron oxide (IO) nanoparticles and anticancer drug paclitaxel (PTX)...
September 13, 2017: ACS Applied Materials & Interfaces
Wanlu Zhang, Guangji Li, Yinlei Lin, Liying Wang, Shuqing Wu
We aimed to introduce hydrophilic sulfobetaine-type zwitterionic groups to macromolecular chains of copolymers to construct novel copolymer hydrogels with anti-protein-fouling performance that could be used as soft contact lens (SCL) materials. Using hydroxyethyl methacrylate (HEMA), N-vinyl pyrrolidinone (NVP) and sulfobetaine methacrylate (SBMA) as comonomers, several copolymer hydrogels with different SBMA contents, poly(HEMA-NVP-SBMA), are synthesized via radical copolymerization in an aqueous phase. Surface chemistry, structural morphologies, water contact angle (WCA), equilibrium water content (EWC), visible light transmittance and tensile mechanical properties are investigated...
August 11, 2017: Journal of Biomaterials Science. Polymer Edition
Marleen Wilde, Rebecca J Green, Michael R Sanders, Francesca Greco
Understanding how polymers interact with biological membranes is important for the development of polymer based therapeutics and wider biomedical applications. Here, biophysical methods (surface pressure measurements, external reflection FTIR) have been used to investigate the interaction between PAMAM dendrimers (Generation 5 or 4.5) and anionic (DPPG) or zwitterionic (DPPC) model membranes. We observed a concentration-dependent binding behaviour of both PAMAM species to both model membranes; however, equivalent levels of penetration into DPPC monolayers required approximately 10-fold higher dendrimer concentrations than for penetration into DPPG monolayers...
August 10, 2017: Journal of Drug Targeting
Ho Joon Kwon, Yunki Lee, Le Thi Phuong, Gyeung Mi Seon, Eunsuk Kim, Jong Chul Park, Hyunjin Yoon, Ki Dong Park
Introducing antifouling property to biomaterial surfaces has been considered an effective method for preventing the failure of implanted devices. In order to achieve this, the immobilization of zwitterions on biomaterial surfaces has been proven to be an excellent way of improving anti-adhesive potency. In this study, poly(sulfobetaine-co-tyramine), a tyramine-conjugated sulfobetaine polymer, was synthesized and simply grafted onto the surface of polyurethane via a tyrosinase-mediated reaction. Surface characterization by water contact angle measurements, X-ray photoelectron spectroscopy and atomic force microscopy demonstrated that the zwitterionic polymer was successfully introduced onto the surface of polyurethane and remained stable for 7days...
August 4, 2017: Acta Biomaterialia
Xiaomeng Liu, Tongfang Xiao, Fei Wu, Mo-Yuan Shen, Meining Zhang, Hsiao-Hua Yu, Lanqun Mao
Resisting biomolecule adsorption onto the surface of brain-implanted microelectrodes is a key issue for in vivo monitoring of neurochemicals. Herein, we demonstrate that an ultrathin cell-membrane-mimic film of ethylenedioxythiophene tailored with zwitterionic phosphorylcholine (EDOT-PC) electropolymerized onto the surface of a carbon fiber microelectrode (CFE) not only resists protein adsorption but also maintains the sensitivity and time response for in vivo monitoring of dopamine (DA). As a consequence, the as-prepared PEDOT-PC/CFEs could be used as a new reliable platform for tracking DA in vivo and would help understand the physiological and pathological functions of DA...
August 3, 2017: Angewandte Chemie
Urszula Kwolek, Keita Nakai, Anna Pluta, Maria Zatorska, Dawid Wnuk, Sławomir Lasota, Jan Bednar, Marta Michalik, Shin-Ichi Yusa, Mariusz Kepczynski
Polymer vesicles formed by a pair of oppositely charged diblock copolyelectrolytes (PICsomes) are considered as a good alternative to polymersomes formed by amphiphilic copolymers. Here, we report on inherent stability and in vitro biocompatibility of PICsomes prepared from a pair of oppositely charged zwitterionic-ionic copolymers, in which the ionic block is a strong polyelectrolyte. Our results demonstrated that the PICsomes are highly stable over a wide range of pH and temperatures. Direct microscopic observations revealed that the PICsomes retain their morphology in the presence of human serum...
October 1, 2017: Colloids and Surfaces. B, Biointerfaces
Dong Chen, Yu Huang, Shuting Xu, Huangyong Jiang, Jieli Wu, Xin Jin, Xinyuan Zhu
Polymeric drug delivery system termed as "polyprodrug amphiphile" poly(2-methylacryloyloxyethyl phosphorylcholine)-b-poly(10-hydroxy-camptothecin methacrylate (pMPC-b-pHCPT) is developed for the prolonged-acting cancer therapy. It is obtained by two-step reversible addition-fragmentation chain transfer polymerization of zwitterionic monomer MPC and an esterase-responsive polymerizable prodrug methacrylic anhydride-CPT, respectively. This diblock polymer is composed of both antifouling (pMPC) and bioactive (pHCPT) segments and the drug is designed as a building block to construct the polymer skeleton directly...
July 24, 2017: Macromolecular Bioscience
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