UCLA

Bioelectronics are revolutionizing the future of human life by reshaping fields of medicine and healthcare into a more personalized form. Biomechanical-to-electrical energy conversion is a promising pathway to realize battery-free bioelectronics in the era of the Internet of Things. This conversion is available 24 hours a day and provides up to 100 W output for an average person. Current biomechanical energy conversion mechanisms, including piezoelectric and triboelectric effects, suffer limitations such as low current density and high internal impedance, which arise from their power generation mechanism. Additionally, their output performance is vulnerable to the humidity caused by body fluids, which limits their practical deployment in wearable and implantable bioelectronics. Therefore, there exists a demand to search for an unexploited biomechanical-to-electrical energy conversion mechanism featuring high current output, low internal impedance, waterproofness, and robustness under biomechanical stimulus. Thus, we discovered the giant magnetoelastic effect in a soft polymer system, which was further coupled with magnetic induction to invent a soft magnetoelastic generator (MEG) as a fundamentally new platform technology for building up human-body-powered soft bioelectronics. Soft magnetoelastic bioelectronics are intrinsically waterproof since the magnetic fields can penetrate water with negligible intensity loss. Thus, they demonstrated stable performance in wearable and implantable manners without any encapsulation. This breakthrough has opened alternative avenues for practical human-body-centered energy, sensing, and therapeutic applications. Second, the recent development of soft bioelectronic devices for disease prevention, diagnosis, and treatment presents pressing needs for the creation of an intimate interface between electronic systems and dynamically evolving biological tissues for precise physiological measurement. While ultrathin membrane-based soft bioelectronic devices can conform to biological tissue, mechanical mismatches between the solid materials and the biological tissue still exist. Thus, we developed an intimate liquid bioelectronic interface through the creation of a permanent fluidic magnet (PFM). PFM possesses the reconfigurable functionality to change its shape without losing its permanent magnetism. It will bridge the gap between liquid-state magnets and ferromagnetism, thereby unlocking a wide range of possibilities. Unlike traditional biomedical devices, liquid bioelectronics used for ambulatory monitoring enable the continuous assessment of biomechanical activity over extended periods. Uninterrupted monitoring provides a more comprehensive picture of a patient's health status, capturing any irregularities or abnormalities that may occur intermittently or during daily activities. Since magnetic fields can penetrate biological tissues due to their physical mechanisms, here we described the utilization of PFM for different biomedical applications, including injectable bioelectronics, and liquid acoustic sensors.