Determinationofethephonresidueinfruitsandvegetablesbygaschromatographyafterderivatizationwith(trimethylsilyl)diazomethane
-
-
Abstract
An analytical method for the determination of ethephon residue in fruits and vegetables was established by using gas chromatography after derivatization with (trimethylsilyl)diazomethane. The samples were extracted with a mixture of hydrochloric acid and methanol (9 : 1, V/V). It was then extracted with anhydrous ether and subjected to derivatization by (trimethylsilyl)diazomethane. The extracts were determined by gas chromatography with the external standard method and qualitative by gas chromatography-mass spectrometry. The calibration curve of ethephon residue was linear in the range of 0.01-2 mg/L with correlation coefficients higher than 0.999 6. The detection limit of this method was 0.01 mg/kg and the limit of quantification was 0.03 mg/kg. In the samples of fruits and vegetables at spiked levels from 0.01 mg/kg to 1mg/kg, the recovery was 93%-102% with the relative standard deviation from 4.2%-7.3%. The method has the advantages of high accuracy, good sensitivity, and strong anti-interference ability, which can be used for the accurate and rapid determination of ethephon residues in fruits and vegetables.
-
-