气相色谱法测定6种邻苯二甲酸酯痕量组分的固相萃取条件研究

利用固相萃取技术富集了水中6种邻苯二甲酸酯类:邻苯二甲酸二(2-乙基己基)酯(DEHP)、邻苯二甲酸二甲酯(DMP)、邻苯二甲酸二乙酯(DEP)、邻苯二甲酸二丁酯(DBP)、邻苯二甲酸二辛酯(DOP)、邻苯二甲酸丁基苄基酯(BBP)。借助均匀设计法及计算机回归建模优化技术对6种邻苯二甲酸酯类的固相萃取条件进行了设计与优化,得到最佳固相萃取条件为:洗脱剂配比(正己烷与丙酮的体积比)30∶1,洗脱体积2 mL,洗脱速率为4 mL/min,上样速率8 mL/min。富集后的样品用带电子捕获器的毛细管气相色谱检测,方法的线性范围为1~1 000μg/L(DMP、DEP、DOP),0.2~100μg/L(DBP、DEHP),0.1~100μg/L(BBP);线性回归方程的相关系数为0.997 0~1.000,检测限为0.01~0.4μg/L,方法回收率为69.0%~117.0%,相对标准偏差为2.2%~9.5%。

Study on optimization of solid phase extraction(SPE) in GC trace analysis by computer pattern recognition(CRT) technology

One of the environmentally-friendly sample preconcentration technologies the solid phase extraction(SPE) coupled with GC-ECD was employed in the trace analysis of phthalate esters,namely dimethyl phthalate(DMP),diethyl phthalate(DEP),di-n-butyl phthalate(DBP),di-2-ethylhexyl phthalate(DEHP),dioctyl phthalate(DOP),and butyl benzyl phthalate(BBP).Several SPE conditions were optimized by means of homogeneous design and the related mathematical model obtained by computer regressive analysis.The optimal conditions of SPE obtained were volume,4 mL/min for the elution flow rate,and 8 mL/min for the sampling flow rate.The linear response of the proposed method was in the range of 1～1 000 μg/L for DMP,DEP,and DOP;0.2～100 μg/L for DBP and DEHP;and 0.1～100 μg/L for BBP.The correlation coefficient of the regression equation was in the range of 0.997 0～1.000.The detection limits of the method were 0.01～0.4 μg/L.The recovery efficiencies were in the range of 69.0%～117.0% and the RSDs were in the range of 2.2%～9.5%.