Plasma surface modification effects on biodegradability and protein adsorption properties of chitosan films

This study investigates how plasma surface modification influences chitosan film biodegradability and protein adsorption properties. Plasma-modified chitosan films exhibit significantly more hydroxyl and carboxylic acid absorption bands in infrared spectra, and therefore exhibit superior hydrophilicity to that of unmodified chitosan films. The plasma-modified chitosan films exhibit rougher surface morphologies and higher swelling ratios in comparison to unmodified chitosan films. The plasma-modified chitosan films possess enhanced biodegradability in comparison to unmodified chitosan films, because more hydroxyl and carboxylic acid groups are metabolized during biodegradation. The plasma-modified chitosan films exhibit less bovine serum albumin (BSA) adsorption in bicinchoninic acid protein assays because the carboxylic acid group in bovine serum albumin is charge-charge repulsed from the abundant carboxylic acid group on the film surface. The 120 s plasma-modified chitosan film possesses optimal hydrophilicity, swelling property, biodegradability, and the lowest BSA protein adsorption, because prolonged plasma treatment time may cause films surface damage. (C) 2013 Elsevier B.V. All rights reserved.