The Robotics Institute

RI | Seminar | November 12

Robotics Institute Seminar, November 12
Time and Place | Seminar Abstract | Speaker Biography | Speaker Appointments

Surface Modification of Implantable Neural Micro-Electrode Arrays

Xinyan Tracy Cui

Department of Bioengineering

University of Pittsburgh



Time and Place

Mauldin Auditorium (NSH 1305)
3:15 pm
3:30 pm



Interfacing brain to external electronics has enormous research and therapeutic importance. Implantable neural microelectrode arrays allow us to stimulate neurons or record neural activities from the central nervous system.  The silicon based microfabrication technology has made it possible to manufacture neural probes that are small yet have a sophisticated arrangement of electrodes that can communicate with neurons individually. These neural probes have been successfully used in acute neural stimulation and recording.  However, they suffer a general failure in chronic application due to the electrode/brain tissue mismatch.  Various surface modification approaches are being pursued in our lab to improve the neural electrode/brain tissue interface. On the electrode sites, conducting polymers were electrochemically deposited together with different dopants. Biomolecules such as neuron promoting peptides have been incorporated as dopants to promote cell attachment on or neurite outgrowth to the electrodes. It was found that conducting polymer coatings significantly reduced the electrode impedance which is beneficial for the detection of small amplitude neural signals. On the silicon region of the neural probe, the surface was chemically modified to be consisting of polyethylene glycol (PEG) and neuron adhesion molecule L1. PEG is a non-fouling material that inhibits non specific binding of proteins and cells, while L1 can promote neuron adhesion and survival on the probe or at the vicinity. An electrically controlled drug release system via conducting polymer electrode is being explored to locally deliver drugs or neurotrophic factors to either minimize the reactive tissue reaction or promote neuronal ingrowth.


Speaker Biography


Xinyan Tracy Cui is an Assistant Professor of Bioengineering at University of Pittsburgh; she received her PhD in Macromolecular Science and Engineering from University of Michigan in 2002.  Dr. Cui joined the bioengineering department in September 2003. Prior to that, she worked as a research scientist at Unilever Research US in Edgewater, NJ. Her current research interests are focused on neural tissue engineering, neuron/electrode interface and conducting polymer based biosensors, actuators and drug delivery system.  She is also the member of McGowan Institute for Regenerative Medicine and Center for Neural Basis of Cognition.


Speaker Appointments

For appointments, please contact George Stetten.

Related Material

  • Presentation (pdf)


The Robotics Institute is part of the School of Computer Science, Carnegie Mellon University.