氢化物发生-原子荧光光谱法测定水产品中有机硒和无机硒

采用硝酸、双氧水将水产样品中的有机硒氧化成无机硒后测定总硒含量;用50%盐酸提取样品中的无机硒并用硝酸、双氧水消解,测定无机硒含量,再通过差减法获得有机硒的含量。研究结果表明,在优化的工作条件下,硒的检出限为7.1 ng/mL,线性范围为0～20μg/L。经回收实验和实际样品检测,总硒加标回收率为93.88%～107.65%,相对标准偏差(RSD)为0.82%～4.97%;无机硒加标回收率为82.88%～90.10%,RSD为2.33%～7.73%。用标准物质对照,其测定数据完全在标准值范围内。实验表明,该方法线性范围宽,相关性好,精密度和准确度高,可操作性强,应用范围广,适合水产品中有机硒和无机硒测定。

Determination of organic and inorganic selenium in aquatic products by hydride generation- atomic florescence spectrometry

We measured the total selenium content in aquatic product samples after oxidation of organic selenium into inorganic selenium using a nitric acid,perhydrol mixed system.Simultaneously,we measured inorganic selenium content by HG-AFS following extraction of the sample in a HCL(50%) solution and digestion of the water phase in HNO3 and H2O2.Using these data we calculated the organic selenium content of the samples.Un-der optimal conditions,the detection limit of selenium by this method was 7.1 ng/mL and the linear range was between 0–20 μg/L.The recovery rate of total selenium was 93.88%–107.65% and the RSD was 0.82%?????–4.97%.Similarly,the recovery rate of organic selenium was 82.88%–90.10% and the RSD was 2.33%–7.73%.In summary,this method has a wide linear dynamic range and good precision and accuracy,so is suitable for the determination of organic and inorganic selenium in aquatic products.