金试剂(4.4′—双(二乙氨基)二苯基甲硫酮)是金的灵敏显色剂。本文研究了在曲通X—100存在下金试剂与金的显色反应的性质和显色条件。研究表明,金一金试剂一曲通X—100体系显色的最佳酸度为3.5～5.2,络合物的组成,金:金试剂=1:4,络合物表观摩尔吸光系数为1.65×10~5升/克分子·厘米(560纳米处),络合物的不稳定常数为4.79×10~(-22)。在25毫升体积中,金量在0—20微克范围内符合比尔定律。 Gold reagent (4.4’-bis (diethylamino) diphenyl methylthione) is a gold sensitive developer. In this paper, the color reaction conditions of gold reagent and gold in the presence of Triton X-100 were studied. The results showed that the optimal acidity of the gold-gold reagent Xitong X-100 system for color development was 3.5-5.2. The composition of complex, gold: gold reagent = 1: 4, and the apparent molar absorptivity of complex was 1.65 × 10-5L / mol · cm (560 nm). The unstable constant of the complex was 4.79 × 10 ~ (-22). In the 25 ml volume, the gold content complies with Beer’s law in the 0-20 microgram range.