Determination of zearalenone in traditional Chinese medicinal plants and related products by HPLC-FLD

A HPLC-FLD method has been developed and validated for zearalenone (ZON) in 107 widely consumed Chinese medicinal herbs and related products collected from different regions of China. Samples were extracted with methanol/water (80 : 20, v/v), and the extracts were cleaned-up through immunoaffinity columns (IAC). ZON was quantified by HPLC with fluorescence detection. Recoveries from three different medicinal herbs spiked with ZON at levels ranging from 30 to 600 mu g kg(-1) were from 80.8 to 98.3%. The limit of detection was 9.5 mu g kg(-1), based on a signal-to-noise ratio of 3 : 1. Naturally occurring ZON was only found in coix seed medicinal herb (all nine samples), with levels ranging from 18.7 to 211.4 mu g kg(-1). Positive results were confirmed by UV spectrum and LC-ESI-MS/MS. This is the first report of ZON contamination of a Chinese medicinal herb.