St. John's wort HLPC test method endorsed by USP in upcoming publication.
This article was originally published in The Tan Sheet
Executive Summary
ST. JOHN'S WORT HPLC TEST METHOD ENDORSED BY USP over older methods used by the dietary supplement industry. The U.S. Pharmacopeia will publish its recommendation to use high performance liquid chromatography to test the potency of St. John's wort products in its next bimonthly Pharmacopeial Forum and will accept public comment on the recommendation. USP prefers HPLC to earlier UV methods including the DAC-1986 and DAC-1991 tests because it is a more discriminating procedure; HPLC allows quantitation of several marker substances such as hypericin, pseudohypericin and hyperforin while DAC-86 and DAC-91 are unable to separate out key ingredients from product excipients. The USP standards monograph on St. John's wort is due out in November.