Simplified determination of combined residues of prochloraz and its metabolites in vegetable, fruit and wheat samples by gas chromatography

This paper describes a gas chromatographic method for the determination of combined residues of prochloraz and its metabolites in various plant materials, including vegetables, fruits, seeds, grains and roots. The method is much simpler than previous ones as it does not require steam distillation; it consists of preliminary extraction of the sample, hydrolysis with pyridine hydrochloride in a test tube, extraction of the 2,4,6-trichlorophenol without the aid of steam distillation/continuous extraction, derivatization with diazomethane and gas chromatographic determination using electron-capture detection. The method is very rapid and can be done in a test tube; detection limit is from 0.01 to 0.50 mg/kg; recoveries are dependent on concentration of analyte and sample matrix; the determined values were found in the region of 72-102%.