气相色谱-高分辨双聚焦磁质谱测定水中超痕量多氯萘

摘要

A method for ultra-trace PCNs in water was established by solid-phase extraction-gas chromatogra-phy-double-focusing high-resolution mass spectrometry.The influencing factors were discussed such as solid-phase extraction solvent,solid phase extraction column and electron bombardment energy.The good linearity of the method was obtained from 0.500 ng/L to 500 ng/L,detection limits of the method from 0.005 ng/L to 0.01 ng/L at 1 L sample,recoveries of matrix samples from 70.2% to 1 10%,RSD from 2.7% to 8.7%.This method has high selec-tivity,high sensitivity and high precision,which can monitor PCNs in complex matrices perfectly.%采用固相萃取法处理水样，气相色谱-高分辨双聚焦磁质谱法测定水中超痕量多氯萘，同位素内标法定量，并对样品前处理条件和仪器条件进行优化。试验表明：方法在0．500 ng/L～500 ng/L范围内线性良好；当取样体积为1 L时，方法检出限为0．005 ng/L～0．01 ng/L；对实际水样进行2个质量浓度水平的加标回收试验，平行测定6次的 RSD为2．7％～8．7％，回收率为70．2％～110％。方法适用性试验表明，水样中复杂的基质对测定无影响。