Abstract:

A gas chromatographic (GC) method was developed for the determination of 2,3,5-triiodobenzoic acid (TIBA) in vegetables. The main steps in sample preparation prior to the injection of processed samples into a GC system equipped with an electron capture detector consisted of acidification with 0.1 mol/L hydrochloric acid, extraction with methylene dichloride under ultrasonic assistance, methylation with trimethylsilyl diazomethane and clean-up on a florisil solid phase extraction (SPE). Retention time was used for qualification and external standard method for quantification. Some figures of merit the method developed including sensitivity, accuracy and precision were evaluated. This method exhibited a limit of detection of 0.001mg/kg for TIBA. Mean recoveries for the analyte in 6 vegetable matrices ranged from 70% to 95.7%. These results suggest that this method is reliable, sensitive, simple and convenient and can provide useful references for the establishment of a national standard method for the determination of TIBA.

Key words: 2,3,5-triiodobenzoic acid, vegetables, derivation, SPE purification, gas chromatography