气相色谱-质谱法测定氟涂料中全氟辛酸及其盐类物质

Determination of Perfluoro-octanoic Acid and Its Salts in Fluoro-paint by Gas-chromatography-Mass Spectrometry

超声萃取技术萃取氟涂料中的全氟辛酸及其盐类物质，萃取液经固相萃取、浓缩后与乙酰化试剂反应，以全氟癸酸甲酯为内标物内标法进行定量测定。对气相色谱-质谱条件进行选择，方法的线性范围为1.0～1×10^5μg·L^-1，相关系数为0．9997，检出限为0．1μg·L^-1，在高低两种浓度水平（100μg·L^-1及1000μg·L^-1PFOA）进行精密度和回收率试验，所得相对标准偏差分别为4．24％和3．58％，回收率在86％～111％之间。

Perfluoro-octanoic acid （PFOA） and its salts were extracted ultrasonically with methanol from the paint sample, and the extract was concentrated by passing through a silica gel column with a layer of anhydrous Na2SO4 （ca. 1 cm） over the silica gel. An aliquot of the sample solution was taken and derivatized with acetylchloride to give methyl ester of PFOA. Methyl ester of perfluorodecanoic acid was used as internal standard in the GC/ MS determination. Analytical conditions of GC/MS were given in detail. Linearity range of the method was found from 1.0-1×10^5μg·L^-1 （r=0.999 7）, with detection limit of 0.1μg·L^-1. Tests for precision and recovery of the method were performed at concentration levels of 100μg·L^-1 and 1 000μg·L^-1 of PFOA, values of RSD＇s （n=6） found were 4. 24% and 3. 58% respectively, and recovery obtained were in the range from 86% to 111%.