A Gelatin-Based Bioadhesive Featuring Mechanically Induced Glue-To-Gel Transition

Abstract

In the field of bioadhesives, the development of machinable adhesives with a “glue-to-gel transition” remains a significant challenge. This study presents a novel design strategy to endow the Gel/Eg adhesive with mechanical machinability. It leverages a combination of hydrogen bond interactions, metal complexation, and the secondary structure of gelatin through a one-step mixing method. Rheological analysis shows that the adhesive exhibits a frequency-dependent “glue-to-gel transition,” maintaining a glue state at low frequencies and transitioning to a gel state at higher frequencies. During stretching, the β-sheet structure transforms into a random coil structure. Moreover, the adhesive features excellent water resistance, a low water swelling ratio, strong adhesion strength, high extensibility, instantaneous adhesion, instantaneous self-healing, and both biocompatibility and hemocompatibility. These attributes enable the Gel/Eg adhesive to exhibit multiple fault-tolerance capabilities on tissue surfaces, highlighting its potential for diverse biomedical applications.