Department of Materials Science and Engineering Spring Seminar Series: Xinyan (Tracy) Cui

Description

Xinyan (Tracy) Cui, a professor of bioengineering at the University of Pittsburgh, will give a talk titled "Materials Strategies Towards Chronic and Multimodal Neural Interface" for the Department of Materials Science and Engineering.

Abstract:

Microelectrode array (MEA) devices, placed in the nervous system to record and modulate neuroactivity have demonstrated success in neuroscience research and neural prosthesis applications. Functionalizing the microelectrode sites on MEAs to enable neurochemical sensing and drug delivery adds additional dimensions of information exchange and presents tremendous potential for understanding neural circuits and treating neurological diseases. In this talk, I will introduce the methods by which we enable chemical sensing and delivery from MEAs. By incorporating nanocarbon into the conducting polymer electrode coating, we achieved direct detection of electroactive species such as dopamine, melatonin, and serotonin. By immobilizing enzymes or aptamers on nanostructured electrodes, we achieved multisite detection of glutamate, GABA, and cocaine. By incorporating nanocarriers into conducting polymer coating, we enabled on-demand drug delivery. We demonstrated in vivo multisite and multiple analyte detection or neurotransmitter delivery along with neural recording from our multimodal neural probes. To overcome the challenges in chronic neural interface, we use quantitative histology, explant analysis, and 2-photon imaging to uncover the mechanism of sensing/recording performance degradation and revealed biofouling, inflammatory host response, as well as material degradations. We use several bioengineering strategies to minimize these failure modes. First, materials and devices that mimic the mechanical properties of the neural tissue have shown to significantly improve device-tissue integration. Secondly, biomimetic coatings and drug delivery have been applied to reduce biofouling and inflammatory responses. These approaches may be combined to achieve long-term and high-fidelity multimodal neural interfacing.