Evaluation of a silica-based monolithic column in the HPLC analysis of taxanes

The Merck KGaA Chromolith RP-18 column is based on a unique sorbent material consisting of a monolithic rod which has a high internal area and porosity, allowing quality separations in a minimum of time. The use of such a silica-based monolithic column has been applied to one of our most challenging HPLC separations, that is the impurity profiling of an analog of Taxol(R). Different types of conventional HPLC columns with silica particle-based packings, as well as the Chromolith RP-18 column, have been investigated with a combination of mobile phases to achieve the separation of all the impurities of a synthetic taxane currently under development. The performance of the Merck KGaA Chromolith column was found to compare quite favorably to a conventional silica particle-based column.