研究了蛋白质与 7-苯基偶氮 -1 ,8-二羟萘 -3 ,6-二磺酸的显色反应。在 p H2 .7的缓冲溶液中 ,7-苯基偶氮 -1 ,8-二羟萘 -3 ,6-二磺酸与蛋白质形成红紫色复合物 ,λmax为 564 nm,ε为 1 .3× 1 0 5L· mol- 1· cm- 1,线性范围为 6.6～ 1 3 2 mg/ L。实验证实7-苯基偶氮 -1 ,8-二羟萘 -3 ,6-二磺酸与蛋白质的作用符合 Pesavento模式。所提出的方法不经任何预处理可直接测定血清和花生中的蛋白质 The color reaction of protein with 7-phenylazo-1, 8-dihydronaphthalene-3,6-disulfonic acid was studied. The 7-phenylazo-1,8-dihydronaphthalene-3,6-disulfonic acid forms a magenta complex with the protein in p H2 .7 buffer at λmax of 564 nm and ε of 1.3 × 105L · mol-1 · cm-1, linear range of 6.6 ~ 132 mg / L. Experiments confirmed that 7-phenylazo-1, 8-dihydronaphthalene-3,6-disulfonic acid and protein role in line with Pesavento mode. The proposed method allows direct determination of the protein in serum and peanut without any pretreatment