In situ forming elastin-like polypeptide hydrogel for injectable drug delivery applications

In situ forming hydrogels are widely explored as injectable drug delivery systems for biomedical applications. It is important for these hydrogels to undergo gelation and deliver the drug in a timely manner upon administration. In this study, lysine-rich elastin-like polypeptide (ELP) and aldehyde-presenting alginate are crosslinked via Schiff base formation under ambient conditions to generate hydrogel. The physicomechanical and drug release properties of the alginate-ELP hydrogel are conveniently controlled by the concentrations of alginate and ELP. Furthermore, due to the thermoresponsiveness of ELP, the alginate-ELP hydrogel undergoes reversible swelling/deswelling at the transition temperature near the physiological temperature. Therefore, the drug release from the alginate-ELP hydrogel is expedited via thermoresponsive deswelling. Taken together, the in situ forming alginate-ELP hydrogel is a highly attractive injectable drug delivery system capable of programmable release characteristics