Friday, August 7, 2015
URSP Student Thao Tran Determines the Stability of Novel Implantable Microelectrode Arrays with Electrochemical Impedance Measurements
My major is bioengineering. I am interested in learning how to use available medical devices and build new devices to make bio-measurements. Besides, I want to learn more about how to process and analyze data in order to solve health related problems. This project gives me the opportunity in doing what I always want to do. During this summer, I am be able to gain hands on experience from recording impedance of microelectrode arrays (MEAs), to work on my data analysis skills and to gain understanding about electrochemical impedance measurements. My plan is going to graduate school, so I believe that having an opportunity to conduct research with my mentor Hamid will be a good preparation for my future years in graduate school. When I first started, my proposal was about characterizing the impedance profile of shape memory polymers; however, I was not able to do it due to a connection problem of the board. As the probe was put in the bath at 60˚C, the water vaporized and got into the board of the probe which then made a connection problem and the measurement could not be obtained. I tried to seal the board with silicon, but it did not solve the problem. My mentor then helped me change the direction of my project, so right now what I am working on determining the stability of novel low-cost MEAs. This new MEAs are from University of Texas (UTD), and I want to know if this new UTD arrays can be used for monitoring cultured neuronal network recording in the lab. On weekly basis, I monitor the impedance profile of three UTD arrays at different electrode sites and develop the Matlab code to plot them. When I am not doing the measurement, I put them in the incubator at 37˚C. Last week, the impedance went bad for two UTD arrays, and I was not sure what caused it. I later discovered that there was some water leaking out of the ring, which affected the measurement. I realized that the glue on the UTD arrays were not good enough for a long time use. This might happen because when the ring was first glued; the contact surface was not clean which then made the ring easy to fall off. I tried to detach the ring completely, washed the surface with deionized water and let it dry overnight. The next day when I came in, I tried to re-glue the ring carefully and let it air dry overnight. On the following day, the impedance went back to normal range again. As the impedance went back to normal range again, I was very happy. I felt great as I was able to solve a problem myself.