聚丙烯酰胺活化过氧化氢氧化邻苯三酚红催化褪色光度法测定痕量钴

Catalytic Spectrophotometry for the determination of Trace Cobalt based on oxidizing discoloration reaction of Pyrogallol Red with Polyacrylamide as activating agent

在pH=8.3硼酸-硼砂缓冲溶液中,聚丙烯酰胺(PAM)活化钴(II)催化过氧化氢氧化邻苯三酚红(PGR)使之褪色的指示反应,确定了催化褪色反应测定钴(II)的动力学条件,建立了测定痕量钴的高灵敏度的褪色光度法。此法线性测定范围为0.012～0.28μg/L,检出限为6.0×10-12g/mL,线性回归方程为△A=0.1045+1.199Cco2+(μg/L),r=0.9994。当加入PAM时,△A比不加PAM增大6.5倍。常见离子不影响测定。

A new high sensitively catalytic spectrophotometric determination of t race cobalt has been developed.it is based on cataly tic oxidation of pyrogallol red(PGR)by hydrogen peroxide on heating and in the H 3 BO 3-Na 2 B 4 O 7 solution,the pH is 8.3whth polyacry lamide as activating agent.A linear range is obtained form0.0012to 0.28ug/L,and the detection limi t is 6×10-12 g/mL.The regression equation of calibration graph is△A =0.1045+1.199Cco 2+ (ug/L),and the correlation coeffecient is 0.9994.when polyacrylamide is added,the△A increases 6.5times.The frequent i on does not affect the determination of cobalt,and it has been applied in the determination of cobalt in human hair and tea with the satisfactory result.