Cosolvent‐Modulated Supramolecular Chirality Unveils Pronounced Piezoelectric Response in Peptide‐Based Nanomaterials

Peptide‐based functional biomaterials have attracted widespread interest due to their inherent biocompatibility, biodegradability, and structural tunability. Among functional biomaterials, piezoelectric materials are particularly valuable for developing self‐powered biodevices in biomedical applications. However, peptide‐based piezoresponsive systems remain largely underexplored. In this study, we present a chromophore‐conjugated peptide (PEP‐A) that self‐assembles into nanomaterials exhibiting either piezo‐active or inactive states, with the functional behaviour closely linked to their chiroptical properties under different solvent conditions. Through a comprehensive investigation involving spectroscopy, microscopy, and atomistic simulations, we uncover how cosolvent‐induced modulation of the self‐assembly process co‐governs chiroptical and piezoelectric properties. Interestingly, PEP‐A forms elongated nanofibers in pure water that are both chiroptically and piezoelectrically inactive. However, the introduction of a minimal amount of cosolvent (1% DMSO or 1% DMF) triggers the emergence of supramolecular chirality alongside a significant piezoresponse, revealing a direct correlation between macroscopic chirality and piezoelectric functionality. Our findings highlight how subtle changes in the assembly environment can drive profound shifts in material properties, offering a powerful strategy to design responsive piezoelectric biomaterials. This study provides a novel approach to designing next‐generation, responsive, peptide‐based piezoelectric biomaterials for biomedical and bioelectronic applications.