SPE逐步分离技术应用于常用果蔬防腐保鲜剂残留量检测的研究

Study of Residue Preservatives Thiabendazole,o-Phenylphenol and Diphenyl in Fruits and Vegetables by SPE-Separation Technology

建立固相萃取逐步分离-紫外分光光度法测定果蔬中残留的噻苯咪唑、邻苯基苯酚、联苯的检测方法。样品经高速涡轮旋转石油醚∶乙酸乙酯(2∶1)提取,30%甲醇溶液上样,C18固相萃取柱富集、净化、分离三种残留防腐剂,分别采用30%乙醇(酸,pH 2.5)溶液、55%甲醇(碱,pH 11.5)溶液、75%乙醇(酸,pH2.5)溶液依次洗脱分离固相柱中被保留的噻苯咪唑、邻苯基苯酚、联苯,对洗脱液进行紫外分光光度法检测。结果表明:三种防腐剂在1～10μg.mL-1的范围内呈良好线性关系,相关系数r>0.999 8。样品加标回收率为72.1%～103.5%,相对标准偏差在1.2%～7.7%,样品最低检测限分别为0.09,0.5和0.1μg.mL-1。该方法简便、灵敏、快速,能够满足同时测定果蔬中防腐剂残留量的要求。

The residue of thiabendazole, o-phenylphenol and diphenyl in vegetables and fruits was detected by solid-phase extraction and ultraviolet-spectrophotometry. Samples were extracted under basic conditions with petroleum ether： ethyl acetate（2：1 ）. The analytes were first enriched, purified and separated through a C18 solid-phase extraction column. Thiabendazole, o-phe-nylphenol and diphenyl in the C18 solid-phase extraction column were eluted with 30% ethanol-acid solution （pH 2. 5）, 55 % methanol -alkaline solution（pH 11.5） and 75 % ethanol-acid solution（pH 2.5） respectively , then detected hy ultraviolet-spectro- photometry. The linear ranges were from 1 to 10 μg.mL-1 with a good linear relationship （r〉0. 999 8） for thiabendazole, o- phenylphenol and diphenyl. The recovery range was from 72. 1% to 103.5%, with the relative standard deviations between 1.2% and 7.7%. The limit of detection （S/N=3） was 0.09μg·mL 1 （TBZ）, 0.5μg.mL-1 （OPP） and 0. 1μg.mL-1 （DP）. The method was successfully applied to residues of preservatives in fruits and vegetables. These results indicated that this method is simple, rapid and sensitive for the simultaneous determination requirements of residues in vegetables and fruits.