测汞仪原子吸收光谱法测定野生食用菌中的总汞

目的建立应用测汞仪直接测定野生食用菌中总汞含量的测定方法。方法样品经均质器粉碎,称量后,直接进样。样品在催化管内加热分解,在氧气的作用下,汞在齐化管内与金粉反应被捕集下来,形成金汞齐,再经高温使金汞齐分解成汞原子蒸气经载气带入吸收池,在253.7 nm处进行吸收测定。结果测汞仪检测方法线性范围:0.0~1000 ng/L,检出限为0.005 ng/m L,相关系数(R2)优于0.999,相对标准偏差(RSD)小于1.5%,回收率大于99%。结论用此仪器检测的方法无需进行样品前处理、进样量少、方法灵敏度高、精密度好、结果准确可靠、操作简单快速、没有试剂污染、检测速度快和运行成本不高,适用于野生食用菌中总汞的测定。

Determination of total mercury in wild mushroom by mercury analyzer-cold atomic absorption

Objective To establish a determination method of total mercury content in wild edible fungus by using mercury vapourmeter. Methods The samples were smashed by homogenizer, and then direct injection of the samples was processed after weighing. The samples were disintegrated by heating in catalytic tube. Driven by oxygen, the mercury was gathered in the amalgamation tube when they reacted with powdered gold, forming the gold amalgam. Next, the gold amalgam was decomposed into atomic vapor by high heat and carried into the absorption pool with gas. Finally, the absorption was measured at 253.7 nm. Results The linear range using the method of mercury vapourmeter was between 0.0 to 1000 ng/L, the detection limit was 0.005 ng/mL, correlation coefficient (R2) was better than 0.999, the relative standard deviation (RSD) was less than 1.5%, and the recovery was greater than 99%. Conclusion This method needs no sample preparation, and shows little sample quantity, high sensitivity, good precision, accuracy and reliability, simple operation, no reagent pollution, fast detection speed and low running cost and it is suitable for the determination of total mercury content in wild edible fungus.