双水相体系中食用色素与蛋白质作用光谱行为研究

在聚乙二醇-2000(PEG)-硫酸铵-食用色素双水相体系中，研究了PEG相中食用色素与蛋白质复合物光谱行为。实验了溶液酸度，盐浓度，PEG用量，反应时间，反应温度，共存物质等对体系测定的影响。结果表明，在pH 8的缓冲溶液条件下，樱桃红(BS)与人血清白蛋白(HSA)复合物的最大吸收在541 nm处，比单纯樱桃红红移13 nm，复合物表观摩尔吸光系数为9.4×104 L·mol-1·cm-1,用摩尔比法求得最大结合数为40，蛋白质浓度在0～21.07 mg·L-1范围内具有线性关系。用加入不同类型表面活性剂方法，探讨了食用色素樱桃红与蛋白质之间的作用机理。

The Spectroscopic Study on the Interaction between Edible Pigment and Human Serum Albumin in Two-Phase Aqueous Systems

In polyethylene glycol 2000 (PEG)-(NH4)2SO4-edible pigment two-phase aqueous systems, the spectroscopic behaviour of the complexes of edible pigment and human serum albumin in PEG phase was investigated. Effects of different acidity, quantities of PEG and salt, reaction time, and coexistent matter on the determination of systems were discussed. Experimental results show that compared to BS spectra, the maximum wavelength of the complex of human serum albumin shifted to the red by 13 nm in buffer solution at pH 8, the maximum binding number of 40 was measured by molar ratio method, and the apparent molar absorptivity was 9.4 x 10(4) L x mol(-1) x cm(-1). The linear range was 0-21.07 mg x L(-1). With different surfactant, the interaction mechanism of protein and edible pigment was discussed.