分散液相微萃取-气相色谱法快速测定甘蔗中特丁硫磷残留

Simplified Method for Determination of Terbufos Residues in Sugarcane Using DLLME–GC

采用分散液相微萃取(DLLME)与气相色谱–火焰光度检测(GC–FPD)联用技术建立了快速测定甘蔗中特丁硫磷残留的新方法。考察了萃取剂种类和体积、分散剂种类和体积、萃取时间与离心时间和盐度等因素对萃取效果的影响,并确立了最佳萃取条件,采用外标法定量。标样在0.1～5.0μg/mL范围内线性关系良好,相关系数为0.996。结果表明,在最佳萃取条件下,平均富集倍数达到456.03±20.01,平均回收率为84.4%～90.31%(n=3),RSD为3.19%～5.88%,特丁硫磷在甘蔗中的检出限为0.02 mg/kg。

A simplified and rapid method was developed for the determination of terbufos residues in sugarcane by dispersive liquid-liquid microextraction （DLLME） combined with gas chromatography-flame photometric detection （GC-FPD）. Some experimental parameters that influence extraction efficiency, such as the kind and volume of disperser solvents and extraction solvents, extraction time, addition of salt and pH, were investigated. And the optimal experimental conditions were obtained, quantitative analysis was carried out using external standard method. The correlation coefficient of the calibration curve was 0.996 in 0.1-5.0 ug/mL. The results showed that under the optimum conditions, the enrichment factors for the terbufos were about 456.03 ± 20.01, the recoveries for standard addition fell in the range of 84.4%-90.31% （n=3） and the relative standard deviations （RSD） were 3.19%-5.88%. The limit of quantification （LOQ） of terbufos in sugaicane was 0.02 mg/kg at the signal/noise （S/N） ratio of 3.