POLY 27 |
| Many enzyme catalyzed biosensors employ NAD+-dependent enzymes, such as the alcohol and aldehyde dehydrogenases. While the fuel is oxidized, the coenzyme NAD+ is reduced. In many bioelectrodes, NADH is the redox species that is actually detected, or oxidized, at the electrode surface. Dye polymers investigated in this research have been demonstrated to catalyze the oxidation of NADH and are currently being used to catalyze the oxidation of NADH in biosensors. To determine the most effective polymer, several were tested for their electrochemical flux, including: poly(methylene green), poly(methylene blue), poly(azure A), poly(azure B), poly(azure C) , poly(toluidine blue O). All of the polymers tested catalyze the oxidation of NADH to some extent. Based on this assay, poly(methylene blue) has the highest ÊD1/2 value. Assuming the Ê value for each polymer is approximately the same given the structure of the monomers are similar, it is implied that PMB has the highest diffusion coefficient and therefore optimally allows the analyte access to the electrode surface in order to be oxidized. Both poly(methylene blue) and poly(toluidine blue O) have substantially higher ÊD1/2 values than poly(methylene green), which is currently used to catalyze the oxidation of NADH in our research group. Therefore, the performance of glucose-dehydrogenase-based biosensors will be compared for these three polymers. |
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Undergraduate Research in Polymer Science
8:15 AM-12:00 PM, Sunday, April 6, 2008 Hilton New Orleans Riverside -- Grand Salon 16, Oral
Division of Polymer Chemistry |