Injectable and Self-Healing Thiazolidine-Crosslinked Hydrogels: Synthesis and Characterization

Self-healing, injectable, and responsive hydrogels are of increasing interest, particularly for biomedical applications. In this work, an original thiazolidine-based polyacrylamide hydrogel was synthesized via the condensation of two polyacrylamides carrying aldehyde and 1,2-aminothiol side groups, respectively. The hydrolytic stability and the viscoelastic properties of the hydrogel were investigated under acidic and physiological pHs. Rheological studies showed that the thiazolidine-based hydrogels exhibit dynamic properties resulting from the reversible formation of the thiazolidine linkages. Attractive self-healing ability and shear-thinning behavior were observed, rendering these hydrogels injectable through a needle. In addition, the hydrogels display a highly pH-dependent stability, making them potential candidates for drug encapsulation and controlled delivery.