Determination of ethephon residues in maize samples by headspace gas chromatography

A headspace-gas chromatography-flame ionization detector (HS-GC-FID) method was used to determine the ethephon residues in maize samples and the influence of different headspace and chromatographic conditions on determination was analyzed, finally a headspace-gas chromatography method was developed for the analysis of ethephon in maize matrix.Maize samples were firstly extracted by methanol, then concentrated after centrifuging, and finally detected by the HS-GC-FID method.The linearity was good and the correlation coefficients (R2) was 0.9999.Recovery experiments were conducted and the average recoveries were from 72.01% to 90.85% with relative standard deviation varying from 1.07% to 5.70%.The detection limit of the method was 0.1mg/kg.The result obtained indicated that this method was simple and safe with satisfying recovery, and therefore it was suitable for the determination of ethephon residues in maize samples.