Comparison of ultraviolet detection, evaporative light scattering detection and charged aerosol detection methods for liquid-chromatographic determination of anti-diabetic drugs.

Recently, charged aerosol detection (CAD), a new kind of universal detection method, has been widely employed in the HPLC system. In the present study, four kinds of anti-diabetic drug standards, glipizide, gliclazide, glibenclamide and glimepiride were determined by ultraviolet (UV) detection, evaporative light scattering detection (ELSD) and the aforementioned CAD. The results were compared with reference to linearity, accuracy, precision and limit of detection (LOD). All of the experiments were performed on a reverse phase column with water and acetonitrile as the mobile phase. Separations were achieved under the same chromatographic conditions for each detection method. As a result, CAD generated nearly uniform responses compared with UV detection and ELSD. It showed the best accuracy and LOD among 3 detectors and had similar precision with UV detection at higher concentrations while UV detection showed a better precision at lower concentrations than did CAD or ELSD. The LOD of CAD, in fact, can be up to two times higher than that of ELSD. The UV and ELSD linearity was satisfactory at R(2)>0.99, though in the case of CAD, a log-log transformation was needed. The proposed methods were also applied to the real anti-diabetic drugs and diabetes-related dietary supplements.