Terephthalohydrazido cross-linked chitosan hydrogels: synthesis, characterization and applications

Two new hydrogels have been synthesized by incorporating terephthalohydrazido linkages into chitosan Schiff base (TCsSB) and chitosan (TCs). They swell at pH 4 more than at pH 9 and 7. TCs has a higher activity against most of the tested microbes as indicated from its lower MIC values than that measured by the reference drugs Vancomycin and Amphotericin B. Evaluation of the cytotoxicity impacts of TCsSB and TCs revealed that they are safe on normal cells of human. Their adsorption capacity toward some heavy metal ions could be arranged as follows: Co+2 > Ni+2 > Cu+2 > Cd+2 ions.