Lee, Kendall

Understanding the complex interplay between electrical activity and neurochemical signaling is essential for advancing neuromodulation therapies, yet current technologies often measure these modalities in isolation and suffer from technical limitations such as stimulation artifacts. To address these challenges, we developed the Multifunctional Apparatus for Voltammetry, Electrophysiology, and Neuromodulation (MAVEN), a compact, battery-powered platform designed for high-resolution, concurrent multimodal data acquisition. Preclinical validation in both small- and large-animal models demonstrated that MAVEN provides stable, high-fidelity multimodal readouts while effectively minimizing stimulation artifacts during simultaneous programmable neurostimulation. By capturing phasic and tonic neurochemical changes, alongside real-time electrophysiological data, we established the system's feasibility for continuous monitoring. Beyond its utility in investigating the mechanisms of neurological and neuropsychiatric disorders, MAVEN has been engineered as a versatile analytical platform. Recent successful applications in monitoring pharmacological agents, such as vancomycin, further demonstrate its potential as a robust point-of-care device for real-time diagnostic and therapeutic monitoring. These results position MAVEN not only as a powerful tool for developing personalized, closed-loop neuromodulation strategies but also as a next-generation analytical device capable of broader clinical and bio-sensing applications.

ABSTRACT Real time, chronic electrochemical detection of neurotransmitters will provide a positive step in the treatment and understanding of neurological disease. However, current electrodes using carbon fibers (CF) fail to perform chronically. While diamond‐based coatings show promise in improving their longevity, achieving a uniform layer of such coatings on CFs is challenging, and the electrodes often lose sensitivity after coating. In this work, a complete and uniform boron‐doped nanocrystalline material grown in a diamond reactor (B‐NCD) was developed to coat CF microelectrodes for neurochemical sensing. The coating was characterized electrically, optically, mechanically, and chemically. The B‐NCD coated CF electrodes were able to detect phasic dopamine at a sensitivity comparable to the most widely used alternatives (uncoated and PEDOT:Nafion coated CFs). During biofouling testing, the B‐NCD coated CF electrodes demonstrated better stability than uncoated CFs and comparable performance to PEDOT:Nafion coated CFs. Moreover, B‐NCD exhibited no signs of degradation during consecutive FSCV applications, while uncoated and PEDOT:Nafion coated CF electrodes degraded significantly over time. Furthermore, the B‐NCD coating supported the survival and development of neurons and astrocytes in vitro, exhibited excellent adhesion and durability during mechanical bending testing, and enabled successful in vivo recording of phasic dopamine release in the rat brain. Overall, B‐NCD coated CFs present as an ideal candidate for chronic, flexible neural implantable electrodes for long‐term neurochemical monitoring.