改进的湿法消解-原子荧光光谱法测定海产品中总砷

An improved method for the determination of total arsenic in seafood using wet digestion coupling with atomic fluorescence spectrometer

目的:建立准确稳定的测定动植物性海产品中总砷的分析方法。方法:采用硝酸、高氯酸、硫酸混合酸体系对海产品进行湿法消解,利用氢化物发生原子荧光光谱法测定样品总砷含量。结果:对植物性和动物性海产品分别进行最佳消解条件的摸索,同时优化检测条件。得出最佳条件如下:还原剂硼氢化钾(KBH4)浓度为2%;灯电流,60 mA;载气流量,400 ml/min;酸性介质,5%盐酸,砷在浓度范围0μg/L^40.0μg/L内线性关系良好,线性相关系数为0.9998,检出限为0.072μg/L。采用国家标准物质黄鱼GBW08573和海带GBW08517进行方法验证,所测结果均在标准参考值允许范围内,六次平行测定相对标准偏差小于3.8%。利用此方法对部分酒店的海产品进行监督检测,结果可靠。结论:该方法准确灵敏、简便高效,适用于海产品中总砷的测定。

Objective：To establish a stable and precise method for the determination of total arsenic in seafood.Methods： After a pretreatment with nitric acid/perchloric acid/sulfuric acid tri-acid digestion process,we used atomic fluorescence spectrometer methodology to detect total As in seafood.Results： Under the optimized pretreatment process and detection conditions： KBH4 concentraton,2%（w/w）;lamp current,60 mA;flow rate of carrying gas,400 ml/min;carrying flow,5% HCl,wide linear relationship was achieved in the range of 0 μg/L^40.0 μg/L with relative coefficient of 0.9998 and the detection limit was estimated to be 0.072 μg/L.The proposed procedure was validated by applying it for the determination of total As in Certified Reference Material GBW08573 and GBW08517（China）.Results were satisfactory with RSDs of 6 replicate experiments less than 3.8%.The proposed method was sucessfully applied to detect total As in seafood supplied by Ningbo hotels.Conclusion： The present method is precise and reliable for the determination of total As in seafood.