分散固相萃取离子色谱质谱法测定乳制品中硫氰酸盐质量浓度

摘要

A method for the determination of thiocyanate in dairy products by ion chromatography mass spectrometry was established.Dairy products thiocyanate in water by ultrasonic extraction,protein precipitation with 3％ acetic acid,with dispersive solid phase extraction for sample putification,0.22 M aqueous membrane extraction,ion chromatography mass spectrometry detection,external standard method for quantitative analysis,and purification methods on samples,ion chromatography and mass spectrometry connection condition temperature and spray cone voltage were optimized.The linear range was 0.01～0.5 mg/L,the correlation coefficient was 0.996,determination limit (3 S/N) is 0.2 mg/kg and the limit of detection (10 S/N)was 0.6 mg/kg.Recoveries were 9L0％～96.9％ with RSD (n=10) of 5.78～9.81％ at the three different standards levels of 2.0,5.0,10.0 mg/kg.The method is simple,sensitive,accurate,cheap,and could be applied in the determination of chlorfluazuron in food.%建立了离子色谱质谱法测定乳制品中硫氰酸盐含量的方法.乳制品中硫氰酸盐经水超声提取后,用3％乙酸沉淀蛋白,以分散固相萃取法进行样品净化,提取液过0.22μm水相滤膜,离子色谱质谱联用仪检测,外标法定量.同时对样品净化方式,离子色谱-质谱连接方式,喷雾温度和锥孔电压等条件进行了优化.结果表明:硫氰酸盐在0.01 ～ 0.5 mg/L范围内线性良好,相关系数为0.996,测定限(以信噪比S/N≥3计)为0.2 mg/kg,定量限(以信噪比S/N≥10计)为0.6 mg/kg.在2.0,5.0,10.0 mg/kg三个添加水平下进行了回收率和精密度实验,加标回收率在91.0％～96.9％之间,相对标准偏差RSD (n=10)为5.78 ～ 9.81％.该方法操作简单、抗干扰能力强、灵敏度高、稳定性好、成本低廉,可用于乳制品中硫氰酸盐的日常检测.