Interactions of drugs and spin probes with hydrophobically modified polyelectrolyte hydrogels based on N-isopropylacrylamide

摘要: Abstract Thermally responsive hydrogels of N-isopropylacrylamide containing hydrophobic comonomers were synthesized by free radical polymerization in both toluene and water. Various monomers used, i.e. methyl methacrylate, hexylacrylate, hexafluoroisopropylmethacrylate hexafluorobutylmethacrylate. Also polymers hydrophilic methacrylic acid synthesized. The swelling properties the polymers, as well 30 wt% ephedrine or ibuprofen investigated pure water at temperatures from 20°C to 46°C. ratios gels depended on ratio structural units polymer, network structures gels. drug was bound polyacid causing deswelling due electrostatic interactions. Ephedrine did not affect neural gels, however. Addition made all collapse room temperature no matter whether neutral acidic. Interactions between spin probes, 4-benzoxy-2,2,6,6-tetramethylpiperidine-1-oxyl (BZONO) 4-amino-2,2,6,6-tetramethylpiperidine-1-oxyl (amino-TEMPO), polymer studied using electron paramagnetic resonance spectroscopy. probe BZONO resided below lower critical solution (LCST) interactions, but dissolved, least partially, aqueous phase above temperature. distribution gel hydrophobicity polymer. amino-TEMPO partially into