INSTITUTUL NAÅ¢IONAL DE CERCETARE-DEZVOLTARE - ICECHIM

3. Chemistry in medical and pharmaceutical applications - PELECTROCHEMISTRY AND DETECTION OF LIPOIC ACIDMariana Marin 1 , Cecilia Lete 1 , Bogdan Manolescu 2 and Mihaela Badea Doni 31 Romanian Academy, Institute of Physical Chemistry, Bucharest,Romania,mariana_marin12@yahoo.com2 University Politehnica of Bucharest, Faculty of Applied Chemistry and Materials Sciences,Department of Organic Chemistry, Bucharest, Romania3 National Research –Development Institute for Chemistry and Petrochemistry, ICECHIM,Department of Biotehnology, Splaiul Independentei, 202, 061821 Bucharest, Romaniaα-Lipoic acid ((R)-5-(1,2-dithiolan-3-yl)pentanoic acid) is a disulphide derivative of octanoicacid with strong antioxidant properties. In the human body the lipoic acid LA is reduced todihydrolipoic acid (DHLA). Both oxidized and reduced forms of LA diminish the oxidativestress by scavenging of reactive oxygen species (ROS), nitric oxygen species (RNOS) or bymetal chelating. Moreover, the LA can regenerate other endogenous antioxidants, such asglutathione, vitamin C and vitamin E. The influence of pH on electrochemical oxidation ofLA at platinum electrodes using cyclic voltammetry and differential pulse voltammetry wasstudied. The response of the platinum electrode towards LA was founded to be linear withinconcentration range 50 and 800 M. The obtained sensitivity of platinum electrode for LAwas 4.17 x 10 -7 A/ M.