RESUMO
The electrochemical properties of a new non-steroidal anti-inflammatory drug (2-hydroxy-4-methylphenyl-2-aminothiazole hydrochloride; CBS-113 A) have been studied using voltammetry in direct current and cyclic modes at glassy carbon disk electrodes. The results show an oxidative process with a diffusion-controlled and a reversible mechanism; these data agree with those obtained in a reversed-phase high-performance liquid chromatography (HPLC) system coupled either with amperometric (single glassy carbon electrode) or coulometric detection (two porous graphite electrodes in series) set at potentials of +0.65 V (vs. Ag/AgCl) and +0.4 V (vs. Pd/H2), respectively. Similar electrochemical properties were found for 2-hydroxyphenyl-2-amino-5'-methylthiazole hydrochloride (RD-1546) which is a potential internal standard. An HPLC system coupled with a UV detector (lambda = 272 nm) and an amperometric detector (+0.65 V) showed a gain in sensitivity of about 10 using electrochemical detection (ED) for the determination of CBS-113 A in human plasma. Linearity range, precision and accuracy were calculated and showed the potential application of HPLC-ED to pharmacokinetic studies of CBS-113 A in plasma.
