催化过氧化氢氧化铬黑T褪色光度法测定痕量锰(Ⅱ)

Catalytic Spectrophotometric Determination of Trace Manganese Based on the Oxidizing Discoloration Reaction Between Eriochrome Black T and Hydrogen Peroxide

在pH11.0的Na2B4O7 NaOH缓冲溶液中十二烷基磺酸钠(DBS)可增敏Mn(Ⅱ)催化过氧化氢氧化铬黑T(EBT)的褪色反应.据此建立了催化褪色光度法测定痕量锰(Ⅱ)的新方法.锰(Ⅱ)浓度在5.0～12.0μg/L范围内服从比耳定律,回归方程△A=-0.014+0.032CMn(Ⅱ)(μg/L),r=0.9999,检出限0.5ng/mL.应用该法测定人发和茶叶中的Mn(Ⅱ),测定结果满意.

A new catalytic spectrophotometric determination of trace manganese has been developed based on catalytic oxidizing discoloration of eriochrome black T with hydrogen peroxide using sodium dodecylbenzene sulfonate as sensitizer in Na\-2B\-4O\-7NaOH buffer solution at pH 11.0. The Beer′s law is obeyed in the range of 5.0～12.0 μg/L, the linear regression equation is △A=-0.014+0.032C\-Mn(Ⅱ)(μg/L), r=0.999 9, the detection limit for manganese is 0.5 ng/mL. The method has been applied to the determination of Mn(Ⅱ) in the hair and tea samples with satisfactory results.