Determination of zearalenone in corn by laser fluorimetry.

By combining laser fluorimetry with high pressure liquid chromatography, we are able to detect and quantitate the naturally fluorescent mycotoxin, zearalenone, in contaminated corn samples. Experiments with zearalenone standards show a linear fluorimeter response over four orders of magnitude with a detection limit of 300 pg zearalenone injected onto a C,8 reverse phase column. The corn samples are first purified using a small silica gel column. The recovery from this step is 86% over the range from 5 ppb to 2.5 ppm. Based on the magnitude of the zearalenone signals compared to the flatness of the base line for zearalenone-free corn samples, a limit of 5 ppb is placed on the detection of zearalenone by this procedure.