A CMOS Nanosensing System For Continuous Brain Multianalyte Monitoring

Continuous and real-time monitoring of brain biochemical markers is essential to deepen our understanding of neural disorders and to develop effective treatments. However, such a system is not currently available. This study presents a multiplexed sensing system that consists of a complementary metal-oxide-semiconductor field-effect transistor (CMOS FET) array. pH sensing has confirmed the sensors' high sensitivity to ion sensing in buffered solutions. Successful functionalization of the sensors with 3-aminopropyltrimethoxysilane (APTES) and a glutaraldehyde cross-linker has enabled the nanosensing system to measure multiple neurotransmitters and extracellular fluid compounds simultaneously. A prototype nanosensing system has been successfully demonstrated to individually measure lactate and gamma-aminobutyric acid (GABA) at micromolar concentrations. These initial findings are promising for the integration of this nanosensing microchip with a microdialysis catheter for continuous, unrestricted monitoring of these neurotransmitters in real time. The insights obtained from this innovative approach could also inform future research across various chronic conditions in neurology, psychiatry, behavioral science, and other medical fields, leading to improved monitoring, prediction, and prevention strategies.