title: Influence of some factors affecting antibacterial activity of PVA/Chitosan based hydrogels synthesized by gamma irradiation.
abstract: Poly (vinyl alcohol) hydrogels containing different concentrations of chitosan with molecular weight of 471 and 101 kDa were crosslinked by gamma irradiation at a dose of 25 kGy. The swelling behavior, gel content and morphological structure of the blend were investigated. The antibacterial effect, as a function of chitosan content and molecular weight in the hydrogel, was investigated against Escherichia coli and Bacillus subtilis. With increasing chitosan content the equilibrium degree of swelling of the blend increased and the gel fraction decreased. Results of antibacterial activity of chitosan revealed that chitosan was more effective in inhibiting growth of gram positive bacteria than that of gram negative ones. It was observed that, the chitosan content as well as its molecular weight has a direct influence on bacteria growth inhibition. The higher the chitosan content in the blend and the higher its initial molecular weight, the larger was the inhibition zone diameter. The bacteria growth inhibition was attributed to the diffusion of entrapped chitosan from the hydrogel blend to the culture medium.
authors.affiliation: Department of Irradiation Technology, Nuclear Research Center of Algiers, BP-399, Algiers, Algeria. tahtatdja@yahoo.fr
authors.forename: Djamel
authors.initials: D
authors.lastname: Tahtat
authors.forename: Mohamed
authors.initials: M
authors.lastname: Mahlous
authors.forename: Samah
authors.initials: S
authors.lastname: Benamer
authors.forename: Assia
authors.initials: A
authors.lastname: Nacer Khodja
authors.forename: Souad
authors.initials: S
authors.lastname: Larbi Youcef
authors.forename: Nadjet
authors.initials: N
authors.lastname: Hadjarab
authors.forename: Wassila
authors.initials: W
authors.lastname: Mezaache
mesh_terms: D000900:Anti-Bacterial Agents / Q000737:chemistry / Q000494:pharmacology*; D001412:Bacillus subtilis / Q000187:drug effects; D001672:Biocompatible Materials; D048271:Chitosan / Q000737:chemistry / Q000494:pharmacology*; D004926:Escherichia coli / Q000187:drug effects; D005720:Gamma Rays; D020100:Hydrogels / Q000737:chemistry*; D008422:Materials Testing; D008855:Microscopy, Electron, Scanning; D011142:Polyvinyl Alcohol / Q000737:chemistry / Q000494:pharmacology*; D013499:Surface Properties
chemical_list: D000900:Anti-Bacterial Agents; D001672:Biocompatible Materials; D020100:Hydrogels; D011142:Polyvinyl Alcohol; D048271:Chitosan