冷原子吸收法测定水产品中总汞含量

Determination of Total Mercury in Aquatic Products by Cold Atomic Absorption Spectrometry

采用DMA-80直接测汞仪测定水产品中的总汞含量。对取样量大小和升温方法进行了优化。从线性范围、方法检出限、方法准确度及精密度等方面进行了方法学验证。结果表明：取样量在0.080 0~0.160 0 g间测定结果最佳;对升温方法优化最终实现进样时间仅需262 s;建立了高浓度（50~400 ng）和低浓度（0~20 ng）范围的2条标准测定曲线,可实现不同汞含量水平的样品定量测定;方法检出限为0.06μg/kg;对两种标准物质测定的结果均在其参考值范围内且相对标准偏差均小于3.6%。直接测汞仪测定无需对样品进行消解等复杂的前处理过程,能够实现固体样品直接进样,具有定量范围宽、准确度高、精密度好、检出限低、测定速度快等优点,可作为测定水产品中总汞含量的一种理想方法。

A method was proposed for determination of total mercury content in aquatic products by DMA-80 Direct Mercury Analyzer. The conditions of sample amount and heating method were optimized and method validation was examined from the linear range, detection limit, method accuracy and precision and oth-er aspects. Experimental results showed that the best sample amount was in the range of 0.080 0-0.160 0 g and the injection time was only 262 s after optimization of heating method. Two standard curves with the range of high concentration（50-400 ng） and low concentration（0-20 ng） were established which could quantify dif-ferent levels of mercury in samples determined. The detection limit was 0.06 μg/kg and the detection results of standard reference materials were all in the range of reference value, with RSDs all less than 3.6%. Without digestion or complex pre-processing and with the advantages of wide quantitative range, high accura cy, good precision, low detection limit and fast determination speed.,the method could be used as an ideal method for determination of total mercury in aquatic products.