(39b) On Chip Electrochemical Detection of Biomarkers From Cell Cultures On Microfluidic Reactors

Clean water is not a luxury but a necessity. While clean water is bountiful in the United States, the same cannot be said for the soldiers who are out in the field. It would be advantageous for these soldiers to have a sophisticated device that can not only monitor water samples, but actually indicate which organs in the body might be at risk to any toxins within the sample. The devices presented offer such a solution. This research builds on recent scientific advances in microfabrication of human organ structures to further create new simulated organs containing the relevant chemical functionality that mimics the toxic responses as well as detection schemes to measure assault of toxins in specific organs. Organs of specific interest (heart, liver, etc) are mounted in separate channels within the glass/PDMS device. A water sample is injected into the device and partitioned between the different organs. One can then monitor any effects of the toxin on individual cell lines. Typical analysis of cell lines includes fluorescence. However, this type of detection is not instantaneous. What would be best is a detection format that allows for real-time data of toxin effects on each cell line. To do this, superoxide (a biomarker for toxin assault) is monitored by microelectrodes patterned below each cell sample. Each electrode is modified by anchoring Cytochrome C onto the gold surface via a thiol layer. By supplying a specific potential, the concentration of superoxide present can be monitored amperometrically. Response, calibration, and figures of merit of such devices, thus far, will be presented.