优化的湿法消解-氢化物原子荧光光谱法测定海产品中总砷

Determination of total arsenic in seafood by optimized wet digestion-hydride generation atomic fluorescence spectrometry

目的通过湿法消解海产品的研究,建立科学准确稳定的海产品中总砷测定的分析方法。方法采取硝酸、高氯酸和硫酸混合体系并通过优化条件进行消解样品,利用氢化物原子荧光光谱法进行测定。结果砷在0μg/L^40μg/L浓度范围内呈良好线性关系,相关系数均大于0.999,测定相对标准偏差小于2.3%,通过对能力验证CNAS T0508鱼粉考核样、国家标准物质GBW08521紫菜以及国家标准物质GBW08573黄鱼的方法验证,检测结果均在标准参考值允许范围内,考核样鱼粉(7.12 mg/kg)检测值得到满意结果,检测值为7.22 mg/kg,回收率为91.71%~99.19%,黄鱼标准物质(5.08 mg/kg)检测值为5.10 mg/kg,回收率为102.25%~105.94%,紫菜标准物质(41 mg/kg)检测值为41.64 mg/kg,回收率为92.26%。结论该方法操作简便、准确灵敏,特别适用于实验室对海产品中总砷的测定。

Objective To establish a scientific,precise and stable method for determination of total arsenic in seafood based on research of wet digestion. Methods The samples were digested by mixed acid of nitric acid,perchloric acid and sulfuric acid under the improved condition. Then arsenic content was determined using hydride generation atomic fluorescence spectrometry. Results The arsenic showed good linear relationship within the concentration range of 0 μg /L - 40 μg /L,the correlation coefficient was greater than 0. 999,and the relative standard deviation was less than 2. 3%. The method validation on CNAS T0508 fishmeal sample（ 7. 12 mg / kg）,GBW08573 nori（ 5. 08 mg / kg） and GBW08573 yellow croaker（ 41 mg / kg） showed satisfying results,with the detection values of 7. 22 mg / kg,5. 10 mg / kg,41. 64 mg / kg respectively,and the recoveries of 91. 71% - 99. 19%,102. 25% - 105. 94%,92. 26% in that order. Conclusion This method is accurate,sensitive and easy to operate, especially suitable for the determination of total arsenic in seafood.