微量荧光法测定粮食样品中痕量硒－与原荧光法的比较

微量荧光法测定粮食样品中痕量硒，最低检出限为０．３ｎｇ，是原荧光法１／１０；多次测定含硒１５～３９２ｎｇ／ｇ的粮食样品加硒标回收率为９０．６％～９９．３％，对牛肝粉及奶粉标准参考物的测定值均在保证值范围之内；测定含硒１７～２９８ｎｇ／ｇ的粮食样品，变异系数为２．１％～２．６％。另外，微量法还减少了样品及试剂用量，为原法的１／１０，并且省去了原法中去硒硫酸的制备，不仅大大降低了成本，减轻了工作量，而且降低了酸对人体健康的影响和对环境造成的污染。

Comparison between microfluorescence method and fluorescence method in determination of selenium in cereals samples

The microflurescence method is more sensitive than the fluorescence method in the determination of selenium in cereals. The minimum detectable amount is 0. 3ng which is one-tenth of that by fluorescence method. The microfluorescence method is accurate. The recovery rate is 90.6%～99.3%, when samples contain 15 ～ 392ng selenium. The determination vaiue of standard reference materials of bovine liver and milk is in the reference valve. The coefficient of variation is 2.1%～5.4%. Using the method, the quantity of samples as well as reagents can be saved. The preparation of non-selenium sulphuric acid is not required.Less cost and work are needed. This method reduces the hazard caused by acid.