Electrochemical detection of glutathione via redox indicators

ANYL 14

Eden Joy V. Pacsial-Ong, edenjoy@lsu.edu, Robin L. McCarley, tunnel@lsu.edu, Weihua Wang, and Robert Strongin, rstrong@lsu.edu. Chemistry Department and Center for Biomodular Multiscale Systems, Louisiana State University, 232 Choppin Hall, Baton Rouge, LA 70820
The interaction between thiols and electrochemically generated ortho-quinones from catechol analogue indicators is reported. The nucleophilic addition of glutathione (GSH) to the electrogenerated quinone of fluorone black results in its reduced adduct, 1-GSH, which is oxidized at a relatively more anodic potential (~+0.4 V vs. Ag/AgCl). The voltammetric discrimination between 1 and its GSH adduct leads to the proposed reaction mechanism, which was corroborated by comparing the voltammetric responses of analogous catechol indicators with added GSH. The presence of the structurally similar aminothiols—homocysteine (HCY) and cysteine (CYS)—posed no interference in the voltammetric profile of the 1-GSH adduct.
 

Analytical Approaches: Electroanalytical Chemistry
8:30 AM-11:40 AM, Sunday, 10 September 2006 Moscone Center -- Room 124, Oral

Division of Analytical Chemistry

The 232nd ACS National Meeting, San Francisco, CA, September 10-14, 2006