Molybdenum disulfide-graphene oxide coated needle-type microextraction device combined gas chromatography for the determination of five kinds of polychlorin-ated biphenyls in milk
Molybdenum disulfide-graphene oxide(MoS2@GO)nanomaterial was synthesized by the solvothermal method.The MoS2@GO was loaded onto the surface of stainless-steel wire with a diameter of 0.3 mm by the sol-gel method.The prepared fiber was filled into a stainless-steel needle to make a needle-type microextraction device,which was combined with gas chromatography(GC)for the extraction of 5 kinds of polychlorinated biphenyls(PCBs)in milk.The optimal extraction conditions were determined by single factor experiment as follows:extraction temperature of 90℃,extraction time of 25 min,peristaltic pump speed of 30 r/min,magnetic stirrer speed of 30 r/min,desorption temperature of 270℃,desorption time of 4 min,and the amount of added salt of 10%(w/V).Under the optimal conditions,the linear relationship of the method was good(r≥0.991)in the concentration range of 0.025-200 μg/L,the limits of detection were 0.0072-0.0149 μg/L,the limits of quantification were 0.0239-0.0495 μg/L,and the relative standard deviations(RSDs)were less than 9.8%.The established method was applied to the enrichment of PCBs in milk.The recoveries ranged from 80.2%to 93.0%,and the RSDs were less than 8.2%.This method can provide technical support for the analysis and detection of PCBs in food.
NETL
NSTL
万方数据
