对乙酰基偶氮羧光度法测定大豆中可溶性蛋白

摘要

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=3.09×105 L/(mol·cm),蛋白质在10滋g/mL~100滋g/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-Acetylcarboxyazoitself.Itsapparentmolarabsorptivityandlinearrangewere3.09×105L/(mol·cm) and 10 μg/mL-100μg/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.