Entrapment polyacrylate

Because of the high quality of surface smoothness of films, wind-up onto rollers causes adjacent film layers to adhere together, either by static electricity or cold-flow (creep). This is overcome by adding finely divided fillers (less than 1 pm diameter) of, for example, chalk, silica, crosslinked polyacrylates, which roughen the surface allowing entrapped air to keep the successive layers apart. 

A wide range of additives can also be introduced into the sol-gel matrices in order to modulate the hydrophobicity of the materials and to improve enzyme stability, activity and accessibility, leading to hybrid or even composite sol-gel matrices. Polymers [157,179,180] such as polyethyleneglycol, polyvinylpyrrolidone, polyvinylalcohol, polyglycidol, polyethyleneimine, polyacrylate have been simultaneously entrapped with enzymes in a siloxane matrix, as well as organic additives (sugar, amino add)... 

Arthursson P, Edman P, Sjoholm I (1985) Biodegradable microspheres II immune response to a heterologous and an autologous protein entrapped in polyacryl starch microparticles. J Pharmacol Exp Ther 255-260. 

The enzymes have been both physically entrapped in polyacrylamide on nylon netting and chemically bound to polyacrylic acid derivatives both preparations exhibited large measuring times. Improvement of the system in favour of the response time diminished the sensitivity of the sensor. The authors reported a response time between 77 and 235 s and a sensitivity of 40 mV per concentration decade. Besides the low selectivity of the iodide sensitive electrode (thiocyanate, sulfide, cyanide, and silver(I) ions interfere), disturbances by other HRP substrates, e.g. uric acid, ascorbic acid, and Fe(II) ions, restrict the applicability of the method. 

Entrapment Agar, dextrane, alginate, carrageenan, collagen, polyacrylate, polysiloxane, polyvinylalcohol, polyethyleneglycol Calcium phosphate gel... 

A number of additional examples of protein delivery via polysaccharides are available in the scientific and patent literature. Edman et al. (1980) have demonstrated release of carbonic anhydrase, catalase, human serum albumin, and immunoglobulin G from cross-linked biodegradable polyacryl dextrans having molecular weights ranging from 10,000 to 2,000,000. Thermal stability of carbonic anhydrase was found to be enhanced via entrapment in microspheres of the above polymer. Schroder (1984) has shown that... 

Tg measurements have been performed on many other polymers and copolymers including phenol bark resins [71], PS [72-74], p-nitrobenzene substituted polymethacrylates [75], PC [76], polyimines [77], polyurethanes (PU) [78], Novolac resins [71], polyisoprene, polybutadiene, polychloroprene, nitrile rubber, ethylene-propylene-diene terpolymer and butyl rubber [79], bisphenol-A epoxy diacrylate-trimethylolpropane triacrylate [80], mono and dipolyphosphazenes [81], polyethylene glycol-polylactic acid entrapment polymers [82], polyether nitrile copolymers [83], polyacrylate-polyoxyethylene grafts [84], Novolak type thermosets [71], polyester carbonates [85], polyethylene naphthalene, 2,6, dicarboxylate [86], PET-polyethylene 2,6-naphthalone carboxylate blends [87], a-phenyl substituted aromatic-aliphatic polyamides [88], sodium acrylate-methyl methacrylate multiblock copolymers [89], telechelic sulfonate polyester ionomers [90], aromatic polyamides [91], polyimides [91], 4,4"-bis(4-oxyphenoxy)benzophenone diglycidyl ether - 3,4 epoxycyclohexyl methyl 3,4 epoxy cyclohexane carboxylate blends [92], PET [93], polyhydroxybutyrate [94], polyetherimides [95], macrocyclic aromatic disulfide oligomers [96], acrylics [97], PU urea elastomers [97], glass reinforced epoxy resin composites [98], PVOH [99], polymethyl methacrylate-N-phenyl maleimide, styrene copolymers [100], chiral... 

Erythropoietin BHK21, j/2, and L929 cells polyacrylate—alginate gels Entrapped in alginate gel [109]... 

Semi interpenetrating polymer networks pPNs) of carboxymethyl cellulose (CMC) and polyacrylic acid were prepared by Bajpai et. al. [130] and its potential for controlled release of ciprofloxacin were assessed. The IPNs were characterized by IR spectral analysis and ESEM analysis. The entrapped drug was examined for its antibacterial activity and chemical stability. The effects of experimental parameters such as vaiying chemical composition of the IPNs, % loading of Cfe (ciprofloxacin) hydrochloride, pH, and temperature of release medium and presence of salts ions in outer solution were examined on the release profile of the drug. 

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