Deuster P A, Trostmann U H, Bernier L L, Dolev E
Clin Chem. 1987 Apr;33(4):529-32.
We evaluated three methods (two indirect and one direct) for determining the magnesium (Mg) and zinc (Zn) content of erythrocytes, to compare methodologic differences and to establish a method suitable for use in field studies. For the indirect methods, erythrocytes in whole blood were lysed by adding either de-ionized water (I) or nitric acid, 2 mol/L (II). For the direct method (III), erythrocytes were isolated by density centrifugation, washed, then digested in concentrated HNO3. Mg and Zn concentrations were measured by atomic absorption spectrophotometry in plasma and whole blood for the indirect methods, and in the pellet for the direct method. Hematocrit and hemoglobin were measured, and erythrocytes were sized and counted on all samples. Within-run CVs for the three methods ranged from 2.2% with method III for Mg to 5.4% with method I for Zn. CVs for reproducibility of the analytical procedures ranged from 2.6% with method II for Zn to 4.2% with method I for the two cations. Analytical recoveries of added Mg and Zn ranged from 93.8 to 104.7%. When values for the three methods were compared, those by method I were significantly (p less than 0.05) lower than those by methods II and III. Values obtained by method II were 100.1% for Mg and 102.4% for Zn of those by the direct method. Thus, the indirect method with 2 mol/L HNO3 lysing solution provides a reproducible, reliable, accurate, and simple technique for measuring Mg and Zn in erythrocytes.
我们评估了三种测定红细胞中镁（Mg）和锌（Zn）含量的方法（两种间接法和一种直接法），以比较方法学差异并建立一种适用于现场研究的方法。对于间接法，通过加入去离子水（I）或2mol/L硝酸（II）使全血中的红细胞裂解。对于直接法（III），通过密度离心分离红细胞，洗涤后在浓硝酸中消化。对于间接法，通过原子吸收分光光度法测定血浆和全血中的镁和锌浓度，对于直接法，测定沉淀中的镁和锌浓度。测量了血细胞比容和血红蛋白，并对所有样品中的红细胞进行了大小测量和计数。三种方法的批内变异系数范围为，镁含量测定时方法III为2.2%，锌含量测定时方法I为5.4%。分析程序的重复性变异系数范围为，锌含量测定时方法II为2.6%，两种阳离子测定时方法I为4.2%。添加的镁和锌的分析回收率范围为93.8%至104.7%。比较三种方法的值时，方法I的值显著低于方法II和III（p小于0.05）。方法II获得的值，镁含量为直接法的100.1%，锌含量为直接法的102.4%。因此，使用2mol/L硝酸裂解液的间接法为测定红细胞中的镁和锌提供了一种可重复、可靠、准确且简单的技术。
