Flexible fMRI-Compatible Neural Probes with Organic Semiconductor based Multi-modal Sensors for Closed Loop Neuromodulation

Neural probe sensing and modulation have been demonstrated as effective tools for diagnosing and treating numerous neurological disorders as well as for understanding sophisticated connections and functions of neuron circuits. To advance the understanding of neural circuit dynamics and closed-loop neuromodulation, it is essential to investigate the integrated functional processes of the brain circuits using a combination of techniques, including functional Magnetic Resonance Imaging (fMRI), electrophysiology, optical sensing and stimulation, and neurochemistry. Accommodating all these multi-modal functions within a single probe that is also fMRI compatible is a critically important but challenging research problem. The novel flexible fMRI compatible neural probe with multi-modal functions that will be developed in this project addresses the limitations of existing neural probe systems and has the potential to revolutionize a host of applications for fundamental brain research and neurological disorders treatment. Moreover, by integrating research and education, this project will link the research outcomes and the activities of future workforce participants to satisfy the needs of the modern industry for biosensors, neural probe fabrication, and medical instrumentation.The objective of this project is to investigate a flexible neural probe with multi-modal sensing and modulation functions compatible with fMRI for advanced personalized neurological research and treatments. A flexible multi-shank neural probe will be designed and fabricated using polymeric materials to provide deep brain sensing and modulation under fMRI, which enables comprehensive understanding and closed-loop control of the nervous system. The multi-modal functions, including organic electrolyte-gated transistors (OEGTs) based neural potential recording, polymer waveguide-enabled optogenetics and photodiode-based photometry, and organic electrochemical transistors (OECTs) based neurochemical sensors, will be custom integrated into the probe. Compared with traditional electrode-based neural probes, the proposed probe adopts a variety of organic semiconductor (OSC) based sensors for electrical, optical, and chemical sensing, significantly improving the sensitivity and selectivity of the current neural sensing and modulation techniques. To demonstrate the platform’s potential for treating neurological disorders, the novel multi-modal neural probes will be applied in vivo in animal models to dynamically control the activity of target brain neural circuits in a closed loop while simultaneously monitoring their activity pattern using adjacent channels.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.