The Experts below are selected from a list of 324 Experts worldwide ranked by ideXlab platform
Doo Sung Lee - One of the best experts on this subject based on the ideXlab platform.
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ph sensitive and bioadhesive poly β amino ester poly ethylene glycol poly β amino ester triblock copolymer hydrogels with potential for drug delivery in oral mucosal surfaces
Polymer, 2009Co-Authors: Minh Khanh Nguyen, Cong Truc Huynh, Doo Sung LeeAbstract:Abstract A series of novel pH-sensitive triblock copolymers composed of poly(β-amino ester)–poly(ethylene glycol)–poly(β-amino ester) (PAE–PEG–PAE) were synthesized by conjugating poly(β-amino ester) to poly(ethylene glycol). The resulting polymers were characterized by 1H and 13C NMR in CDCl3 and gel permeation chromatography in tetrahydrofuran. The concentrated polymer solutions (30 wt%) exhibited a gel-to-sol transition in the pH range 6.4–7.8. The gel window spanned physiological conditions (37 °C, pH 7.4). After injection into a rat, the copolymer solution (30 wt%) changed to a gel in a short time. This copolymer hydrogel showed bioadhesive properties and in vitro release of lidocaine was controllable.
Mihee Kim - One of the best experts on this subject based on the ideXlab platform.
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spatial distribution of peo ppo peo block copolymer and peo homopolymer in lipid bilayers
Langmuir, 2020Co-Authors: Mihee Kim, Frank Heinrich, Greg Haugstad, Guangcui Yuan, Sushil K Satija, Wenjia Zhang, Hannah S Seo, Joseph M MetzgerAbstract:Maintaining the integrity of cell membranes is indispensable for cellular viability. Poloxamer 188 (P188), a poly(ethylene oxide)-b-poly(propylene oxide)-b-poly(ethylene oxide) (PEO–PPO–PEO) triblo...
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surface plasmon resonance study of the binding of peo ppo peo triblock copolymer and peo homopolymer to supported lipid bilayers
Langmuir, 2018Co-Authors: Mihee Kim, Milan Vala, Christopher T Ertsgaard, Timothy P Lodge, Frank S Bates, Benjamin J HackelAbstract:Poloxamer 188 (P188), a poly(ethylene oxide)-b-poly(propylene oxide)-b-poly(ethylene oxide) triblock copolymer, protects cell membranes against various external stresses, whereas poly(ethylene oxide) (PEO; 8600 g/mol) homopolymer lacks protection efficacy. As part of a comprehensive effort to elucidate the protection mechanism, we used surface plasmon resonance (SPR) to obtain direct evidence of binding of the polymers onto supported lipid bilayers. Binding kinetics and coverage of P188 and PEO were examined and compared. Most notably, PEO exhibited membrane association comparable to that of P188, evidenced by comparable association rate constants and coverage. This result highlights the need for additional mechanistic understanding beyond simple membrane association to explain the differential efficacy of P188 in therapeutic applications.
Yoshio Inoue - One of the best experts on this subject based on the ideXlab platform.
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biodegradable blends of high molecular weight poly ethylene oxide with poly 3 hydroxypropionic acid and poly 3 hydroxybutyric acid a miscibility study by dsc dmta and nmr spectroscopy
Polymer International, 2000Co-Authors: Naoki Asakawa, Yoshio InoueAbstract:The miscibility of high molecular weight poly(ethylene oxide) blends with poly(3-hydroxypropionic acid) and poly(3-hydroxybutyric acid) (P(3HB)) has been investigated by differential scanning calorimetry (DSC), dynamic mechanical thermal analysis (DMTA) and high-resolution solid state 13C nuclear magnetic resonance (NMR). The DSC thermal behaviour of the blends revealed that the binary blends of poly(ethylene oxide)/poly(3-hydroxypropionic acid) (OP blends) were miscible over the whole composition range while the miscibility of poly(ethylene oxide)/poly(3-hydroxybutyric acid) blends (OB blends) was dependent on the blend composition. OB blends were found to be partly miscible at the middle P(3HB) contents (25 %, 50 %) and miscible at other P(3HB) contents (10 %, 75 % and 90 %). Single-phase behaviour for OP blends and phase separation behaviour for OB blends were observed from DMTA. The results from NMR spectroscopy revealed that the two components in the OP50 blend were intimately mixed on a scale of about 35 nm, while the domain sizes in the OB blend with a P(3HB) content of 50 % were larger than about 32 nm. © 2000 Society of Chemical Industry
Ulrich S Schubert - One of the best experts on this subject based on the ideXlab platform.
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hyperbranched poly ethylene glycol copolymers absolute values of the molar mass properties in dilute solution and hydrodynamic homology
Macromolecules, 2015Co-Authors: Igor Perevyazko, Jan Seiwert, Martina Schomer, Holger Frey, Ulrich S Schubert, G M PavlovAbstract:Hyperbranched poly(ethylene glycol) copolymers were synthesized by random anionic ring-opening multibranching copolymerization of ethylene oxide with glycidol as a branching agent, leading to poly(ethylene glycol) structure with glycerol branching points. Extending the available range of molar masses by novel synthesis strategies, a limited extent of control over the degree of polymerization was achieved by variation of the solvent in this copolymerization. Generally, absolute molar mass characterization of hyperbranched polymers still represents an unresolved challenge. A series of the hyperbranched poly(ethylene glycol)-co-(glycerol) copolymers (hbPEGs) of a wide range of molar masses (1400 < M < 1 700 000 g mol–1), degree of branching (DB) = 0.04–0.54, and moderate polydispersity (Mw/Mn) ≈ 2.1 ± 0.2 were studied, in both water and dimethylformamide by the methods of molecular hydrodynamics. Analytical ultracentrifugation, intrinsic viscosity, translational diffusion measurements, and SEC were combined....
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soluble high molecular mass poly ethylene oxide s via self organization
Macromolecules, 2003Co-Authors: Stefan S Schmatloch, Antje M J Van Den Berg, Alexander Alexeev, Harald H Hofmeier, Ulrich S SchubertAbstract:High-molecular-weight poly(ethylene oxide)s are utilized for a wide variety of different applications. Here we present a new strategy for the large-scale synthesis of modified metallosupra- molecular poly(ethylene oxide)s on the basis of the metal-induced self-assembly of bis(2,2':6',2''-terpyrid- 4'-yl)-poly(ethylene oxide)179. The influence of different metal ions (cadmium(II), copper(II), cobalt(II), nickel(II), iron(II)) on the degree of polymerization and the resulting molecular weight were evaluated. Elaborated reaction conditions allow easy access to high-molecular-weight iron(II) coordination polymers via self-organization. The polymers were characterized in detail utilizing 1H NMR, UV/vis spectroscopy, MALDI-TOF-MS, and viscosity measurements. The molecular weight was estimated on the basis of concentration-dependent viscosity measurements to about 80 000 g/mol. Furthermore, the morphology of the utilized telechelic bis(2,2':6',2''-terpyrid-4'-yl)-poly(ethylene oxide)179 and the corresponding coordination polymer was investigated using atomic force microscopy. In particular, the influence of complex formation on the morphology was investigated.
Thomas P Davis - One of the best experts on this subject based on the ideXlab platform.
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synthesis and thermoresponsive solution properties of poly oligo ethylene glycol meth acrylamide s biocompatible peg analogues
Macromolecules, 2012Co-Authors: Giles B H Chua, Peter J Roth, Hien T T Duong, Thomas P Davis, Andrew B LoweAbstract:A library of (meth)acrylamido (co)polymers was prepared by reacting poly(pentafluorophenyl (meth)acrylate) with α-amino, ω-methoxy functionalized di(ethylene glycol), tri(ethylene glycol), and poly(ethylene glycol) (PEG)-350, PEG-750, and PEG-5k, in combination with hexylamine or thyroxine. The resulting copolymers showed an improved solubility in water (higher or absent LCST values) and in alcohols (lower or absent UCST values) than the analogous common series of poly[oligo(ethylene glycol) methyl ether (meth)acrylates]. The polyacrylamido species showed a better solubility than the corresponding polymethacrylamido derivatives of similar molecular weight with all polyacrylamides investigated being water-soluble at temperatures exceeding 90.0 °C. Tunable thermosensitive behavior could be effected by the incorporation of the hydrophobic hexylamide comonomer. Similarly, an acrylamido backbone with grafted oligo(propylene glycol 600) amides exhibited a sharp LCST-type transition around 22.0 °C. The UCST-type...
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synthesis and self assembly of brush type poly poly ethylene glycol methyl ether methacrylate block poly pentafluorostyrene amphiphilic diblock copolymers in aqueous solution
Langmuir, 2010Co-Authors: Benghoon Tan, Hazrat Hussain, Ye Liu, Thomas P DavisAbstract:Well-defined fluorinated brush-like amphiphilic diblock copolymers of poly[poly(ethylene glycol)methyl ether methacrylate] (P(PEGMA)) and poly(pentafluorostyrene) (PPFS) have been successfully synt...