对乙酰基偶氮羧光度法测定大豆中可溶性蛋白

Determination of Soluble Proteins in Soybean by β-Acetylcarboxyazo

紫红色的有机试剂对乙酰基偶氮羧在pH2.90的Britton-Robinson缓冲溶液中,能与蛋白质形成蓝色复合物,λmax为669 nm,比试剂本身红移约92 nm,表观摩尔吸光系数ε669 nm=3.09×105L(/mol·cm),蛋白质在10μg/mL～100μg/mL(BSA)范围内遵循比尔定律。0.1%的TrittonX-100存在,吸光度提高23%。探讨了反应的最佳条件,建立了测定蛋白质的光度分析新方法,用于大豆蛋白的测定,方法操作简便,重现性好,基本无干扰。

Purple β-Acetylcarboxyazo could combine with protein form blue complex in Britton-Robinson buffer at pH 2.90, which presents a maximum absorption at 669 nm with 92 nm of red shift compared to β- Acetylcarboxyazo itself. Its apparent molar absorptivity and linear range were 3.09×10^5 I/（mol, cm） and 10 μg/mL - 100 txg/mL （BSA） . Sensitivity increased 23 % with the presence of 0.1% of TrittonX-100. A new method for determination of soluble proteins in soybean was established under the optional condition. The method is simple, fast, high sensitivity and good reproducibility.