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

摘要

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. Under optimal conditions, the detection limit of selenium by this method was 7.1 ng/mL and the linear range was between 0-20 ug/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.%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.