Optimization of the capillary electrophoresis separation of ranitidine and related compounds

Experimental designs were used as part of a strategy to determine the significant factors controlling separation and the optimum conditions for analysis of ranitidine and related compounds by using capillary electrophoresis. Two-level fractional factorial designs were employed to screen for the significant factors in the separation with six factors studied. It was necessary to use two fractional factorial designs due to significant overall curvature in the first of the designs used in the screening. Central composite designs were applied to determine the optimal conditions for the significant factors. Multi-linear regression and canonical analysis were used in the analysis. The optimization was based on a response function which takes into account all the peaks in the electropherogram. The pH value and the voltage were found to be the most significant factors.