Monitoring Intrinsic Optical Signals in Brain Tissue with Organic Photodetectors

Studies of the living tissue via optical means are able to monitor biological activities such as metabolism, gene expression, and variations in ionic concentration. Organic optoelectronic devices have numerous advantages over traditional inorganic technologies, yet limited examples of their capabilities exist in biomedical applications. An organic photodetector (OPD) with a simple structure acts as a highly sensitive optical sensor for detecting intrinsic optical signals of a living brain tissue. The signals are related to cell volume variations and are essential in detecting biological events, such as metabolism and hypoxia. This work demonstrates for the first time the capability of OPDs to assess biooptical events in neuroscience. Their simple fabrication and the capability for selective absorption of an optical event via tunable chemistry pave the way for their integration in biomedical prostheses with broad applications in bioelectronics.