Journal of Chromatography A vol:764 issue:1 pages:43-53
An isocratic liquid chromatographic method is described using as stationary phase the very stable poly(styrene-divinylbenzene) PLRP-S (8 mu m 1000 Angstrom). The mobile phase is acetonitrile-0.2 M potassium phosphate buffer pH 9.0-water (37:5:up to 100, v/v/v), delivered at a flow-rate of 1.0 ml/min. UV detection is performed at 232 nm. Full factorial design was applied to evaluate the robustness of the method. Quantitative results of a number of commercial samples are presented.