卟啉与镉配位反应及其测定烟草中镉的研究

Studies on Reaction of Cadmium With mesoTetra(4Bromophenyl)Porphyrin and Determination of Cadmium in Tobacco

研究了当Ｔｗｅｎ８０存在时，非水溶性ｍｅｓｏ四（４溴苯基）卟啉（ＴＢｒＰＰ）与镉络合显色反应的条件Ｃｄ与ＴＢｒＰＰ形成络合物的摩尔组成比为１∶１，表观摩尔吸光系数为４．５×１０５ｌ·ｍｏｌ－１·ｃｍ－１，Ｃｄ含量在０～０．３６μｇ·ｍｌ－１内有较好的线性关系，线性回归方程Ａ＝０．０００３４＋０．１６１Ｃ，相关系数ｒ＝０．９９９７，稳定常数为２．６×１０７用于烟草样中痕量镉的测定，与ＡＡＳ值进行比较，获得了令人满意的结果．

The color reaction of Cd(II) with mesoTetra(4Bromophenyl)porphyrin (TBrPP) has been studied in the presence of Tween80 at pH9.0～11.2. The apparent molar absorptivity is 4.5×105l·mol-1·cm-1 measured at maximum absorption 436nm. The molar ratio of TBrPP to Cd(II) is 1∶1. Beer's law is obeyed for Cd(II) in the range of 0～0.36μg·ml-1. The linear equation is A=0.00034 + 0.161C,r=0.9997. The stabilization constant of the complex is 2.6×107. This method has been applied to determine cadmium in tobacco with satisfactory results compared with AAS data.