共振光散射法测定水中痕量总锰

建立一种环境水样中总锰的共振光散射分析新方法。在pH=6.0的Tris-HC l缓冲溶液中,锰(Ⅶ)氧化二甲基亚砜(DMSO)成为二甲基砜(DMSO2),生成的Mn2+与DMSO2结合形成离子缔合物,使体系的共振光散射急聚增强。在优化的实验条件下,在6.3×10-9~7.5×10-5mol/L浓度范围内,体系的△I值与锰(Ⅶ)浓度之间具有良好的线性关系,线性回归方程为△IRLS=-217.3+114.7 c(r=0.999 1);检出限为1.9×10-9mol/L;样品加标回收率为102.3%~106.5%。该法简便,特异,灵敏度高。用于环境水样中总锰的测定,结果满意。

Determination of trace total manganese in water by resonance light scattering method

A novel resonance light scattering method was established for the determination of trace total manganese in environmental water.Mn(Ⅶ) oxidates dimethyl sulfoxide(DMSO) to dimethyl sulfone(DMSO_2) at pH=6.0 of Tris-HCl buffer solution,Mn(Ⅱ) could react with dimethyl sulfone to form an ion association complex,so that the system's scattering intensity of RLS is enhanced.Under the optimal experimental conditions,compared to the system's scattering intensity,Mn(Ⅶ) concentration had a good linear relationship in the range of 6.3×10~(-9)～7.5×10~(-5)mol/L,the linear regression equation was △I_(RLS)= -217.3+ 114.7c (r=0.999 1).The detection limit for total manganese was 1.9×10~(-9)mol /L and the sample recoveries were 102.3%～106.5%.The method was simple, specific,sensitive,and the results of determination of total manganese for environmental water samples were satisfactory.