Analytical Sciences

Abstract − Analytical Sciences, 25(7), 925 (2009).

Selection of the Optimal Solvent Grade for the Mobile Phase in HPLC with Electrochemical Detection Based on FUMI Theory
Akira KOTANI,* Yanan YUAN,*,** Bin YANG,** Yuzuru HAYASHI,*** Rieko MATSUDA,*** and Fumiyo KUSU*
*School of Pharmacy, Tokyo University of Pharmacy and Life Sciences, 1432-1 Horinouchi, Hachioji, Tokyo 192-0392, Japan
**Institute of Chinese Material Medica, China Academy of Chinese Medical Sciences, 16 Dongzhimennei Nanxiaojie, Beijing 100700, China
***National Institute of Health Sciences, 1-18-1 Kami-Yoga, Setagaya, Tokyo 158-8501, Japan
The optimum conditions of the mobile phase for HPLC with electrochemical detection (HPLC-ECD) were selected from among solvents of different grades with the standard deviation (SD) of area measurements based on FUMI (function of mutual information) theory as a criterion. In HPLC-ECD for determining baicalin and baicalein using a phosphoric acid-methanol-water mixture (0.5:60:40, v/v/v) as a mobile phase, the effects of three grades of phosphoric acid, of five grades of methanol, and of seven grades of water on the measurement precision were examined. The mixture, if characterized by the minimum SD of measurements, was selected as the optimal mobile phase. This selection method saves considerable amounts of chemicals and experimental time, and would be a useful exploration technique for the routine check and troubleshooting of HPLC-ECD.