Thermospray liquid chromatographic—mass spectrometric method for the analysis of metribuzin and its metabolites

A thermospray liquid chromatographic—mass spectrometric (TSP LC—MS) method has been developed for the analysis of the herbicide metribuzin and its three major metabolites in plant tissue. Metribuzin and its metabolites exhibited widely varying sensitivities in positive-ion TSP, with metribuzin being the most sensitive and deaminated diketo metribuzin being the least sensitive. All four compounds of interest were detected in an extract of a soybean plant which had been treated with metribuzin.