Piezoelectric Silk-Based Materials for Biomedical Applications
Among other things, the present invention encompasses the recognition that silk materials can exhibit oscillatory behavior via piezoelectricity, much like quartz. When mechanical stress is applied, silk is capable of generating electric charge, which may then be captured. This property, coupled with the biocompatible nature of silk, is useful in a number of applications, including implantable sensors and energy-scavenging tools that can power low-powered devices in vivo. Among other biopolymers, silk is particularly suited for providing stable and robust oscillations when exhibiting piezoelectricity, based in part on its structural rigidity. When piezoelectric silk that can oscillate are certain frequencies is structurally perturbed (e.g., being deformed), such structural alteration can be detected by known methods, providing a basis for a sensing means. In addition, mechanical vibration of silk-based piezoelectric materials provides a means for capturing and storing energy for other purposes (e.g., energy scavenging). The present invention also includes the appreciation that the efficiency of energy conversion may be increased by enhanced alignment of silk fibroin polymers.
US Patent 9,761,789 issued 9/12/2017 (13/876,472)