Certification of a novel matrix reference material for accurate measurements of PFOS and PFOA in prawn

This study aimed to develop Certified Reference Materials (CRMs) for the accurate determination of perfluorooctane sulfonate (PFOS) and perfluorooctanoic acid (PFOA) residues in prawn. The raw materials were prepared by feeding prawns with drugs and then processing them into powder. The homogeneity, stability, and characteristics of these matrix CRMs were examined by liquid chromatography tandem mass spectrometry (LC-MS/MS) and isotope labeling internal standard method. The certified value of PFOS in prawn powder was 30.24 µg/kg with an uncertainty of 0.25 µg/kg (k = 2). The certified value for PFOA in prawn was 20.22 µg/kg with an uncertainty of 0.18 µg/kg (k = 2). The homogeneity of the samples, long-term stability at -20 °C for 6 months, and short-term stability at an extreme temperature of 50 °C for 7 days were also evaluated in detail. The results showed that the samples were stable and homogeneous under the above conditions.