Genotoxicity Study of Carboxymethyl Chitosan-based Hydrogel for Clinical Use

Abstract

A carboxymethyl chitosan-based hydrogel used for hemostatic and anti-adhesive on wounds was assessed by a genotoxicity test. The hydrogel was assessed for its potential to induce bacterial reverse mutation in the histidine auxotroph strains of Salmonella typhimurium and in the tryptophan auxotroph strain of Escherichia coli WP2uvrA. The study was performed with five bacterial test strains at different concentrations of hydrogel, with a negative control, and with five different types of positive controls, both in the presence and absence of a metabolic activation system. In all test strains used, there was no increase in the number of revertant colonies compared to the negative control at any concentration of test item either in the presence of or in the absence of a metabolic activation system. To evaluate additional genotoxicity of carboxymethyl chitosan hydrogel, the chromosome aberration test was performed using a cultured Chinese hamster lung cell line in the absence and presence of a metabolic activation system. The results of the bacterial reverse mutation assay indicated no mutagenic response at the concentration range tested, under the conditions of this study. The chromosome aberration test showed no significant increase of chromosome aberration in cells in metaphase arrest compared to the groups treated with vehicle control. Therefore, the carboxymethyl chitosan-based hydrogel is considered not to induce genotoxicity under the test system utilized.