光度法是测定物料中微量铋的灵敏方法。经典的分光光度法灵敏度很低而不能满足需要。近期发展的铋与DBDTC、磺基萤光酮、邻苯二酚紫、甲基百里酚蓝、ДБФФ等三元配合物体系,灵敏度均属中等,其中只有ДБФФ在CPC存在下是高灵敏的(ε=1.1×10~5)。因此研究铋的新的高灵敏显色剂是有意义的。Саввин等曾合成以4,5-二甲基噻唑为母体的显色剂,但与金属离子反应的灵敏度不高。用我们首次合成的2-(4,5-二甲基噻唑-2-偶氮)-5-二乙氨基苯酚(DMTAE)为试剂(简称H_nR),可明显地提高试剂与金属离子铋(Ⅲ)、镓(Ⅲ)、镉(Ⅱ)等显色反应的灵敏度。在30％乙醇水溶液中或在表面活性剂的胶束增溶作用下,铋的摩尔吸光度达10~5数量级。本文详细 Spectrophotometry is a sensitive method for the determination of trace amounts of bismuth in materials. The sensitivity of classical spectrophotometry is very low and can not meet the need. Recently developed ternary complex systems of bismuth with DBDTC, sulfonylfluorone, pyrochlore violet, methyl thymol blue, ДБФФ all have moderate sensitivity with only ДБФФ being highly sensitive in the presence of CPC (ε = 1.1 × 10 -5). Therefore, the study of bismuth’s new highly sensitive developer is of interest. Саввин had synthesized with 4,5-dimethyl thiazole as the matrix developer, but the sensitivity of metal ions reaction is not high. With our first synthesis of 2- (4,5-dimethylthiazol-2-azo) -5-diethylaminophenol (DMTAE) as a reagent (referred to as H_nR), can significantly improve the reagent and the metal ion bismuth ), Gallium (Ⅲ), cadmium (Ⅱ) and other color reaction sensitivity. The molar absorbance of bismuth is in the order of 10 to 5 in a 30% aqueous solution of ethanol or under micellar solubilization of surfactants. This article is detailed