Analysis of ellagitannins and conjugates of ellagic acid and quercetin in raspberry fruits by LC-MSn

The use of gradient reversed phase HPLC with diode array and MSn detection for the analysis of ellagitannins, ellagic acid conjugates and quercetin conjugates in raspberries (Rubus idaeus L.) is described. MSn is a particularly powerful tool for the analysis of trace levels of natural products in impure extracts as interpretation of fragmentation patterns, coupled in some instances with knowledge of HPLC retention properties, can facilitate the partial identification of components when reference compounds are unavailable. (C) 2003 Elsevier Ltd. All rights reserved.