Injectable and self-healing biobased composite hydrogels as future anticancer therapeutic biomaterials

Abstract Self-healing composite hydrogels are prepared from sustainable biopolymers by a green chemistry approach and analyzed by physicochemical and mechanical characterization techniques for future injectable anticancer biomaterials. Water-soluble chitosan (WSC) was prepared by grafting polyethylene glycol (PEG), glutamic acid and gallic acid onto the chitosan chain by carbodiimide chemistry. This WSC showed fast gelation (t ≈ < 60 seconds) with benzaldehyde-terminated 4-arm-PEG as a crosslinker through an amine/aldehyde Schiff base reaction. The compression modulus of these gels can be controlled between 6 and 67 kPa, which was dependent on both the crosslinker content as well as the total solid content (T%). It showed injectability and complete self-healing ability at the lower solid content (T = 2%). The hydrogel nanocomposites (HNCs) were synthesized together with gold (Au) and silver (Ag) nanoparticles (NPs) and tested for cytotoxicity using fibroblast cells (WI-38) for 48 hours, which showed good biocompatibility. The in-vitro assay against cancer cells (U87MG) for 48 hours indicated that only the HNCs with incorporated AuNPs were effective agents for cancer cell apoptosis in contrast to pristine gel, pure NPs (Ag and AuNPs) and HCNs with AgNPs. Therefore, these HNCs could be effective chemotherapeutic materials for designing anticancer nanomedicines in the future.