火焰原子吸收光谱法同时测定尿中钙镁

采用火焰原子吸收光谱法 ,同时测定了尿中钙和镁的含量 ,确定了钙、镁的最佳测试条件。测定钙时 ,波长 4 2 2 8nm ,空心阴极灯的工作电流 3mA ;测定镁时 ,波长 2 85 2nm ,工作电流 4mA ;燃烧器高度均为 8mm ,空气 乙炔流量比均为 6∶1,狭缝宽度 0 2mm。为了消除磷酸盐、硫酸盐和硅酸盐对测定钙浓度的干扰 ,可以加入释放剂 ,其中氯化镧为最佳释放剂。当稀释比例达到 1∶10 0时 ,可以消除尿基质的干扰。通过对 15例尿样的检测 ,尿样的钙和镁值与文献中所提供的浓度值区间一致 ,方法的回收率为 98%～10 4 % ;对于同一样品测试的标准偏差为 1 8% ,P <0 0 5。

Simultaneous Determination of Calcium and Magnesium in Urines by Flame Atomic Absorption Spectrometry

The contents of calcium and magnesium in urines were simultaneously determined by flame atomic absorption spectrometry. The optimized working conditions were ascertained. For the determination of calcium, the used wavelength was 422.8 nm, and the current of HCL(Hollow Cathode Lamp) was 3 mA; for the determination of magnesium, the used wavelength was 285.2 nm, and the current of HCL (Hollow Cathode Lamp) was 4 mA. The height of burner and the air-acetylene ratio were 8 mm and 6:1, respectively, for the determination of both calcium and magnesium. In order to remove the disturbance of phosphate, sulphate and silicate on the determination of calcium, a releasing reagent can be used. Lanthanum chloride (LaCl3) was tested as a better releasing reagent than strontium chloride (SrCl2). The disturbance of urinary substrate could be avoided after the urines were diluted to 1:100 with distilled water. The concentrations of Ca and Mg in 15 urines were determined under the optimized conditions. The obtained results were consistent with the archived data. The recovery was 96%-104%, the relative standard deviation for a sample was 1.8% with P < 0.05.