A study of the behaviour of some new column materials in the chromatographic analysis of Catharanthus alkaloids

New column-packing materials specially designed for the HPLC analysis of basic compounds have been tested for the analysis of Catharanthus alkaloids. Mobile phase optimization was performed for each column tested. The influence of mobile phase pH, nature and content of the organic modifier and salt concentration on retention, selectivity and resolution was studied. An important factor in the separation proved to be the pH of the eluent, because of the widely different pK(a), values of the analytes. Complete separation was easily achieved on ODS columns, but polymeric materials also gave acceptable results.