Resolution and identification of the acidic fraction of a petroleum ether extract of Radix Rehmanniae Preparata by an evolving chemometric approach

An evolving approach is described for analyzing the acidic components of a petroleum ether extract of Radix Rehmanniae Preparata. The latter was extracted, separated and derivatized. The subsequent separation of the individual components was characterized by GC-MS. The two-way data were resolved into a pure chromatogram and a mass spectrum of each chemical component. The reliability and accuracy of the qualitative results were greatly improved and the degree of the chromatographic separation could be enhanced to a certain extent. This enabled the analysis of complicated practical systems by hyphenated instruments and these advanced methods.