Use of Solid‐Phase Extraction for Improving HPLC Assays of Triterpene Glycosides in Gotu Kola (Centella asiatica), Parthenolide in Feverfew (Tanacetum parthenium), and Valerenic Acids in Valerian (Valeriana officinalis)

Abstract

The use of solid‐phase extraction (SPE) for solving interference problems observed in simple HPLC assays involving nutraceuticals is demonstrated. Anion‐exchange SPE is used to remove an interfering compound coeluting with the triterpene glycoside madecassoside in gotu kola (Centella asiatica). C₁₈ SPE is used to remove an interfering compound coeluting with parthenolide in feverfew (Tanacetum parthenium), and as a general cleanup for valerenic acids in valerian (Valeriana officinalis). In each case, use of a single ultrasonically assisted extraction was verified by comparing the results with multiple extractions.