Electrocatalytic oxidation of Glutation at the surface of NanoZeolite modified caron paste electrode

Glutathione which is present in virtually all mammalian tissues, providesreducing capacity for several reactions and plays animportant role in detoxification of hydrogen peroxide, otherperoxide, and free radicals[1]. Glutathione (GSH) is the most abundantly found non-proteinthiol in living organisms with numerous important roles in proteinand DNA synthesis, transport, catabolism, and metabolism[2]. Electrode surface modification is a field of paramount importance in the modern electrochemistry especially due to the various application possibilities of modified electrodes. In recent years, chemically modified carbon paste electrodes have received increasing attention due to their potential applications in various analysis and also due to its relative ease of electrode preparation and regeneration[3]. The aim of this research is determination of glutathione using zeolite ZSM-5 modified carbon paste electrode. Electrochemical behavior of zeolite modified carbon paste electrode which was dopped with ferrosen (FeZSM-5/CPE), zeolite modified carbon paste electrode (ZSM-5/CPE) and unmodified carbon paste electrode (CPE) were studied by using cyclic voltammetry technique. To prepare modified electrode a mixture of nanosized NiZSM-5 , graphite powder, ferrosen and paraffin oil were blended by hand mixing with a mortar and pestle. The resulting paste was then inserted in a glass tube then The electrical connection was implemented by a copper wire lead fitted into the glass tube. The unmodified carbone paste electrode (CPE), used for comparison, was prepared in the same way but omitting the zeolite and ferosen addition step. The oxidation of glutathione was studied at CPE and fe/ZSM-5/CPE by cyclic voltametric experiment in buffer 14th Annual Electrochemistry Seminar of Iran Materials and Energy Research Center (MERC), 12- 13 Dec, 2018 34 solution then obtained results was compared with each other. In the optimum condition, linear dynamic range (LDR) of glutathione by differential pluse voltammetry and cyclic voltammetry were 4.0×10-5-1.0×10-3 and 8.0×10-5-2×10-3 respectively and the limit of detection was 8.7×10-7 and 1.13×10-6 respectively. The chronoamprometry was studied for the oxidation of glutation at the surface of proposed modified electrode. Through chronoamprometry results the catalytic rate constant for this catalytic electrooxidation was calculated to be 6.75×1011 cm3mol-1s-1 From obtaining result in conclution the poroposed modified electrode was a novel, cheap and easy to use. Then it can be used for determination of glutation in pharmacutical product and pure form.