次甲基兰-溴酸钾体系催化光度法测定溴化物

Catalytic spectrophotometric determination of bromide through methylene blue-potassium bromate system

建立了测定微量的溴化物的催化动力学光度分析方法。在酸性介质中,KBr对KBrO3氧化次甲基兰的反应具有明显的催化作用,使次甲基兰的吸光度减小。结果表明:最大吸收波长为665 nm,KBr浓度在2.0×10-6～2.8×10-5mol/L时与吸光度△A呈良好的线性关系。其线性回归方程为△A=0.0122 c+0.0173,R2=0.9992,检出限为1.1×10-6mol/L,回收率99.8%～101%。RSD为0.47%～0.69%。该方法灵敏度和准确度均较高,适用于药品中微量KBr的测定。

A novel and sensitive catalytic spectrophotometric method for the determination of bromide was developed. In acidic media, KBr has obvious catalytic effect on the oxidation reaction of potassium bromate to methylene blue, which makes the absorbance of methyl blue decrease. The experimental results showed that the maximum absorption wave length was 665 nm and the absorbance had good linear relationship with the concentration in the range of 2. 0 ×10^-6m ~ 2. 8 ×10^-6m mol/L, the linear regression equation and correlation coefficient were △A =0. 0122 c ＋0. 0173 and R2 =0. 9992 respectively, the limit of detection was 1.1 ×10^-6m mol/L, and the recoveries ranged from 99.8% to higher sensitivity and accuracy, and can be applied results. 101% and RSDs were 0.47% ~ 0. 69%. The method has to the detection of the bromide in medicine with satisfactory