Capillary gas chromatographic determination of thiabendazole in citrus and apple juices.

A rapid and simple procedure for the determination of thiabendazole (TBZ) residue in citrus and apple juices is described. A juice sample is made basic with 2M NaOH and applied to a disposable Extrelut prepacked column. TBZ is eluted with hexane-ethyl acetate (3 + 1) from the column. The eluate is evaporated to dryness under reduced pressure and then dissolved in an internal standard solution. TBZ is monitored without derivatization by capillary gas chromatography with nitrogen-phosphorus detection. The recoveries of TBZ added to fruit juices at 0.05-1.0 micrograms/g were 90-96%. The limit of detection of the method for TBZ was 0.01 micrograms/g. The proposed method is rapid, simple, and sensitive and is applicable to the determination of TBZ in commercial fruit juices.