Peptide Glasses with Room Temperature Shaping and Autonomous Self-Healing Capabilities

Biomolecular glasses recently emerged as a promising renewable and benign alternative to conventional glasses, but often they cannot autonomously self-repair. In this study, we adopt a new strategy to arrest the crystallization tendency of dipeptides and leverage high molecular mobility of protected dipeptides to prepare self-healing glassy solids without the application of external stimuli. The peptide glasses are stable under wet conditions and have some promising properties, such as high transmittance of visible light, Young's moduli of up to 16.3 GPa, and heating-free shaping capability. Moreover, a cysteine-lysine dipeptide can be applied as an auxiliary to promote the healing of peptide glasses, which are otherwise unable to automatically recover from mechanical damages. Our findings establish a promising avenue to the design and preparation of healable and shapeable biomolecular glasses that could be highly advantageous for their application as smart coating, optical, and biomedical materials.