Friday, October 28, 2011
Hall 1-2 (San Jose Convention Center)
Adenine is a DNA base that offers vital genetically coded information. In this study an electrochemical sensor for adenine using a carbon paste electrode (CPE) has been developed. The sensing is based on the irreversible oxidation of adenine in strong alkaline media. Comparing with current existent methods for adenine, the CPE approach is simple and fast. The oxidation mechanism of adenine on the surface of the electrode was investigated by cyclic voltammetry. The oxidation can occur in neutral to basic media by voltammetry, and involve several reaction products. The surface electrochemical reaction of adenine on CPE results in the formation of a strongly adsorbed intermediate on the electrode surface. Adenine showed linear concentrations in the range of micromolarity level. In this study we also developed a commercial pencil “sensor” for adenine, which possesses nearly the same response as CPE but with the ease of surface regeneration to overcome the strong adsorption of the surface product. Our presented approach represents a simple, cost-effective alternative to adenine quanfication in the existing protocols for DNA bases. This work was supported by NASA-TSGC-NIP, SACP-UARP, UHD-ORC, Brown Foundation, and Welch Grant (BJ-0027).