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Show HONORS COLLEGE SPRING 2013 Shelley Minteer 230 CHARACTERIZATION OF MITOCHONDRIA-MODIFIED ELECTRODES Tera Nicolo, Fabien Giroud, Sara Koepke (Shelley Minteer) Department of Chemistry University of Utah In order to develop an herbicide detector, yeast, potato, and bovine mitochondria were isolated and immobilized onto Toray paper electrodes. Cyclic voltammetry showed two redox peaks at 186 ± 14 m V a n d -357 ± 24 m V with and E1/2 of-128 mV. Scan rate studies suggested the process was surface limited, and therefore was due to the direct electrochemistry of the mitochondria, and not fuel oxidation. The electrochemistry demonstrated a strong linear dependence on pH similar to that of coenzyme Q10. Cytochrome c and inter-membrane quinones were removed from the mitochondria, showing the observed redox couple was due to the vast mitochondrial qui-none pool. The mitochondria modified electrodes were then exposed to the herbicide parathion, which inhibits Complexes II and V in the electron transport chain. Differential pulse amperom-etry was used to analyze the degree of inhibition and create a calibration curve. The calibration curve for parathion showed a linear relationship between the current and concentration of parathion with a slope of -0.22 ± 0.03 t£_L mg |