Subcutaneous Energy/Signal Transmission Based on Silk Fibroin Up-Conversion Photonic Amplification

Transmission of energy and signals through human skin is critically important for implantable devices. Because near-infrared (NIR) light can easily penetrate through human skin/tissue, in this study we report on silk fibroin (SF) up-conversion photonic amplifiers (SFUCPAs) integrated into optoelectronic devices, which provide a practical approach for subcutaneous charging and communication via NIR lasers. SFUCPAs achieve a 4 times higher fluorescence than the control, which gives rise to a 47.3 time increase in subcutaneous NIR energy conversion efficiency of a single fibrous dye-sensitized solar cell compared with the control. Moreover, the hybrid printed electrodes exhibited reversible switching to NIR exposure with a response time of similar to 1.06/1.63 s for a 3 s ON/OFF switch. Owing to the flexible, biocompatible, and cost-efficient design NIR-driven optoelectronic performance, the SFUCPAs are promising for use in applications of subcutaneous medical electronics for charging, storing information, and controlling implanted devices.

Automated summary

This study introduces silk fibroin up-conversion photonic amplifiers (SFUCPAs) integrated into optoelectronic devices, which provide a practical approach for subcutaneous charging and communication via NIR lasers. SFUCPAs achieve significantly higher fluorescence and energy conversion efficiency compared to controls, and exhibit reversible switching to NIR exposure with a rapid response time. The flexible, biocompatible, and cost-efficient design of SFUCPAs makes them promising for applications in subcutaneous medical electronics for charging, storing information, and controlling implanted devices.