Bioresorbable electronic materials serve as foundations for implantable devices that provide active diagnostic or therapeutic function over a timeframe matched to a biological process, and then disappear within the body to avoid secondary surgical extraction. Approaches to power supply in these physically transient systems are critically important. This paper describes a fully biodegradable, monocrystalline silicon photovoltaic (PV) platform based on microscale cells (microcells) designed to operate at wavelengths with long penetration depths in biological tissues (red and near infrared wavelengths), such that external illumination can provide realistic levels of power. Systematic characterization and theoretical simulations of operation under porcine skin and fat establish a foundational understanding of these systems and their scalability. In vivo studies of a representative platform capable of generating ≈60 µW of electrical power under 4 mm of porcine skin and fat illustrate an ability to operate blue light-emitting diodes (LEDs) as subdermal implants in rats for 3 d. Here, the PV system fully resorbs after 4 months. Histological analysis reveals that the degradation process introduces no inflammatory responses in the surrounding tissues. The results suggest the potential for using silicon photovoltaic microcells as bioresorbable power supplies for various transient biomedical implants.
Bibliographical noteFunding Information:
L.L. and Z.Y. contributed equally to this work. The authors acknowledge support from the Center for Bio-Integrated Electronics, Simpson-Querrey Institute at Northwestern University. K.M. acknowledges support from the NIH T32 DK108742. A.V.-G., J.B., and D.C. acknowledge support from the National Science Foundation (Grant No. #CMMI-1450806) and Northrop Grumman Corporation (Grant No. #63018088). K.J.Y. acknowledges support from the National Research Foundation of Korea (Grant No. NRF-2017M1A2A2048904). X.S. acknowledges support from the National Natural Science Foundation of China (Project 51602172).
© 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim
All Science Journal Classification (ASJC) codes
- Renewable Energy, Sustainability and the Environment
- Materials Science(all)