Poly hydrogel fibers

Gitsov et al 10) produced a nanoreactor fi om laccase and linear poly(ethylene oxide)-dendritic poly(benzyl ether) diblock copolymers. A notable feature of this system is the presence of hydrophobic dendritic pockets that increase the local concentration of water-insoluble organic compounds near the active site where they are oxidized. Li and Hsieh (77) employed a hydrogel fiber membrane, with a large surface area and improved organic solvent solubility in order to facilitate lipase reactions. He (72) grafted lipase onto silica particles, which permitted him to carry out synthesis of polyesters, polycarbonates, polyphosphates, and their copolymers at temperatures up to 150°C. 

Lipase Immobilization on Ultrafine Poly(acrylic acid)-PoIy(vinyl alcohol) Hydrogel Fibers... 

One of the philosophical bases of this work is the relative surface area benefit of microcapsules vs. hollow fibers. It is also felt that the alginate hydrogel would have a higher flux rate than the poly sulfone used in hollow fibers. The study of this technique, however, has only been advanced through a rat model. The survival rate for induced liver failure was 46.7% vs. 0% for untreated animals. 

Other studies are centered on the development of hydrogels that include helicoidal fibers of poly(ethyl-ene terephthalate), in an attempt to simulate natural collagen fibers, in order to generate a material that has mechanical characteristics close to those of the ligaments and can be used as connective replacement tissue.f ... 

Chitin is known to be biodegradable, biocompatible, and nontoxic. It is used in dmg delivery and bio medical applications. It also used in the purification of water especially for the absorption of toxic dyes. Chitin has limited solubility in solvents but chitosan is readily soluble in acidic aqueous solutions and has more tendency to be chemically modified. Chitosan can readily be spun into fibers, cast into films, or precipitated in a variety of micromorphologies from acidic solutions. Min and Kim have reported on the adsorption of acid dyes from wastewater using composites of PAN/chitosan [52]. Shin et al. has reported on copolymers composed of PVA and poly dimethyl siloxanes cross-linked with chitosan to prepare semi IPN hydrogels for application as biomedical materials... 

Immobilization Bv Polymer Binding. A popular approach to small molecule reagent immobilization Is to covalently bind it to a thin polymer film covering the fiber optic end. Hydrogel polymers are preferred for analysis of constituents of aqueous media, and poly-acrylamide (55), poly-vinylalcohol (48), and partially hydrolyzed cellulose acetate (56) films have been described. 

Chemical modification of poly(7-glutamic acid) involving esterification or amidation of the carboxylic group is an approach to obtain materials with potential interest as fibers, films or hydrogels. Electrostatic coupling of poly(7-glutamic acid) with hydrophobic cationic species may also be profited to generate non water soluble stable derivatives. 

Ekaputra, A.K., Prestwich, G.D., Cool, S.M., and Hutmacher, D.W. (2011) The three-dimensional vascularization of growth factor-releasing hybrid scaffold of poly (epsilon-caprolactone)/collagen fibers and hyaluronic acid hydrogel Biomaterials, 32 (32), 8108-8117. 

Maeda et al. [13], First, poly(NIPAAm-co-AAc) was synthesized. The obtained polymer was mixed with p-cyclodextrin. This polymer solution was electrospim into nanofibers and dried at 140°C for 24 h for thermal curing. This fiber mat rapidly shrinks in response to temperature changes over the LCST. The response of this mat is over 100 times faster than that of the typical PNIPAAm hydrogels. 

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