Preparative method for isolating alpha-zearalenol and zearalenone using extracting disk

A liquid chromatographic method is described for the determination of zearalenol and zearalenone in corn. Zearalenol and zearalenone are extracted from corn with methanol-water (1 + 1) and cleaned up using a solid-phase extraction (SPE) disk, separated on a reversed-phase analytical column, and detected with a fluorescence detector. The SPE disk concentrated and cleanly separated zearalenol and zearalenone from sample interferences. Standard calibration curves for zearalenol and zearalenone for the concentration range 25-500 ng/mL were linear. The small extract disk had a column capacity equivalent to 1 g extracted corn. Zearalenol and zearalenone were added at levels ranging from 10 to 2000 ng/g to a control sample that contained no detectable levels of zearalenol and zearalenone. Both toxins were recovered from spiked samples at 106.3 and 103.8%, with coefficients of variation of 7.6 and 13.0%, respectively. The method has an estimated reliable limit of detection and limit of quantitation around 10 and 40 ng/g for each toxin, respectively.