Xinyan Tracy Cui
University of Pittsburgh
Presenting in Track 14: Micro- and Nano-Systems Engineering and Packaging
Presentation Title: Microelectrode Arrays Towards Multimodal and Chronic Neural Interfaces
Abstract: Microfabricated microelectrode array (MEA) devices, implanted in the nervous system to record and modulate neural activity, have become invaluable tools for neuroscience research and neural prosthetic applications. Extending MEAs with neurochemical sensing and targeted drug delivery introduces new dimensions of information exchange and therapeutic capability, with the potential to advance both our understanding of neural circuits and the treatment of neurological disorders.
In this talk, I will present our strategies for fabricating MEAs and enabling chemical sensing and controlled drug delivery. By incorporating nanocarbon materials into conducting polymer coatings, we have achieved direct detection of electroactive species, including dopamine, melatonin, and serotonin. Immobilizing enzymes and aptamers on nanostructured electrodes further enabled multisite detection of glutamate, GABA, and cocaine. In addition, integrating nanocarriers into electrode coatings enables electrically controlled, site-specific drug release. Our multimodal neural probes demonstrate the ability to simultaneously record neural activity while detecting and delivering multiple neurochemicals in free-behaving animals.
Currently, long-term performance of neural interface devices is sub-optimal. To understand and address the challenges associated with long-term implantation, we combine quantitative histology, explant analysis, and two-photon imaging to investigate the mechanisms underlying performance degradation, including biofouling, inflammatory responses, and material failure. We then apply complementary biomaterial strategies to improve long-term device performance. First, designing devices with mechanical properties that better match those of neural tissue can promote tissue integration and reduce mechanical damage. Second, biomimetic coatings and localized drug delivery can mitigate inflammatory responses and biofouling at the device–tissue interface.
Together, these approaches advance the development of long-term, high-fidelity, multimodal neural interfaces capable of not only recording and modulating neural activity but also monitoring and manipulating the in vivo neurochemical environment.
Biography: Dr. Cui is the George M. and Eva M. Bevier Professor of Bioengineering at the University of Pittsburgh. Dr. Cui earned her BE in Polymer Materials and Chemical Engineering and her MS in Biophysics at Tsinghua University in Beijing, China. She went on to earn her PhD in Macromolecular Science and Engineering at the University of Michigan, Ann Arbor, Michigan. Her lab explores the intricate interactions between neural tissues and neural implants, simultaneously developing advanced materials and devices for neural recording and modulation, chemical sensing, drug delivery, and neural tissue engineering, all to advance neuroscience research and therapeutic interventions. Dr. Cui has published extensively, has received more than 17,000 citations for her publications, and holds nine patents (two licensed to industry). For her significant research and technological contributions, she has won numerous hornors and awards, including Fellow of the American Institute for Medical and Biological Engineering (2015), Fellow of the Royal Society of Chemistry (2017), and Senior Member of the National Academy of Innovators (2024), the 2015 Carnegie Science Emerging Female Scientist Award, the 2008 NSF Career Award, and the 2005 Wallace Coulter Translational Research Career Award.