[Determination of 17 plasticizers in dairy food]

A method was established for determination of 17 kinds of plasticizers in infant formula by solid-phase extraction coupled with UPLC-MS/MS.

The plasticizers were extracted from the infant formula with acetonitrile, and purified by solid phase extraction column named OASIS Prime HLB. The analytes were then separated by the chromatographic column (BEH Phenyl, 2.1 mm x 100 mm x 1.7 microm). The ion fragment information analytes were obtained using ultra high performance liquid chromatography-tandem mass spectrometry under multiple reaction monitoring mode and the isotope internal standards were used to quantify by calibration curves.

The method showed a good linearity (R2 > 0.9990) in the range of 0.5-500 microg/L for 17 plasticizers analytes with average recovery rates of 89.8%-119.0% (n = 6) and the relative standard deviation (RSD) within 3.62%-12.60%. The limits of quantification (LOQ) were between 1 microg/kg and 14 microg/kg.

The method is simple, sensitive and accurate, and the sample pretreatment is very convenient especially, is suitable for the determination of 17 plasticizers in infant formula and dairy products.