A Dopamine Driven Dual-Amplifier Strategy for High Performance Bioorganic Piezoelectrics via Secondary-Structure Modulation and Synergistic Molecular Dipoles.

Bio-proteins with intrinsic piezoelectricity are highly promising for bioelectronics due to their tunable conformations, biocompatibility, and biodegradability. However, their practical applications are severely constrained by difficulties in regulating piezoelectric domains and inherent mechanical brittleness. In this study, we propose a small-molecule dual-amplifier strategy to achieve high performance piezoelectric biomaterials. By introducing a dopamine-mediated modulation approach, a silk fibroin-based film with an enhanced piezoelectric coefficient of up to 12.7 pC N- 1 is obtained. This performance boost is attributed to a dual mechanism: the dopamine-induced promotion of β-sheet formation in silk fibroin, which strengthens its intrinsic piezoelectricity, and the synergistic contribution of piezoelectric dipole moments from dopamine. In addition, the film exhibits superior mechanical robustness and flexibility, tunable stability in aqueous environments, as well as excellent in vitro/vivo biocompatibility. When applied to the sensing of temporomandibular joint motion and oral occlusal contact patterns, the resulting sensors demonstrate high sensitivity and long-term stability. Furthermore, the generated voltage signals can be effectively encoded and converted into digital information, facilitating data processing and analysis. These results demonstrate small-molecule modulation represents a reliable approach for enhancing the piezoelectricity of structurally complex proteins, offering a simple and innovative pathway toward the development of high-performance bio-piezoelectric materials for digital healthcare.