Novel chitosan-acetyl isatin polymer derivatives: synthesis, characterization, and applications in bone tissue engineering

Abstract

Novel crystalline and thermally stable chitosan-N-acetylisatin (Chs-NAI) polymer derivatives were synthesized by chitosan modification. These polymers were formed by insertion of β-cyclodextrin (βCD) and doping with zinc oxide nanoparticles (ZnO NPs) yielding pseudopolyrotaxane (Chs-NAI/βCD), Chs-NAI/ZnO-NPs, and Chs-NAI/βCD/ZnO NP composites. The chemical structure and morphology of the newly prepared polymers were investigated by FTIR, XRD, and SEM analyses. Also, the optical properties and thermal stability analysis of the synthesized polymers were examined. These results showed that the use of β-CD or ZnO NPs to modify the polymer (Chs-NAI) dramatically improves the thermal stability and optical properties of the synthesized polymer. The weight losses of the synthesized polymers are 66%, 56%, 48%, and 59% in Chs-NAI, Chs-NAI/βCD, Chs-NAI/ZnO, and Chs-NAI/βCD/ZnO, respectively. For mineral deposition, Chs-NAI/βCD/ZnO was presoaked with a PO43− containing solution before being immersed in a Ca2+ containing solution. The properties of Chs-NAI/βCD/ZnO nanoparticles/calcium phosphate materials were examined to confirm the deposition of the calcium phosphate on the Chs-NAI/βCD/ZnO nanoparticles surface using different techniques. Based on the results of the tests on the Vero cell lines, Chs-NAI/βCD/ZnO NPs)/calcium phosphate demonstrated very mild cytotoxicity. In addition, the feasibility of a wide variety of hybrid was assessed with an MTT test, and it was determined that they were noncytotoxic under a variety of hybrid concentrations.