Topology in Biological Piezoelectric Materials.

Topology is fundamental in determining the properties and functions of biological piezoelectric materials by influencing service performances across multiple scales, from nanoscale molecular arrangements to macroscopic assembly structures. At each scale, topology governs electrical, mechanical, and biological behaviors, facilitating multifunctional integration and multi-field coupling advances. Recent progress demonstrates the potential of topological optimization to enhance piezoelectric coefficients and enable complex functionalities. Strategies such as multi-scale design, machine learning-guided optimization, and precision fabrication techniques are being explored to address persistent challenges, including limited energy conversion efficiency, long-term stability, and biocompatibility. Critical applications include health monitoring, biosensing, energy harvesting, and disease treatment, highlighting opportunities and unresolved technical bottlenecks. Future research directions are discussed to present theoretical insights and practical pathways to the development of biological piezoelectric materials.