淀粉/聚丙烯酸/大豆蛋白三元复合物形成过程的光谱学研究

基于荧光光谱和共振光散射光谱（RLS）并结合UV紫外光谱研究了可溶性淀粉、大豆分离蛋白（SPI）以及聚（丙烯酸）（PAA）在溶液中形成三元非共价复合物的过程，并考察了其热稳定性能。荧光实验结果表明SPI和淀粉可以分别与PAA发生相互作用，其相应的表观结合常数分别为2.02×105和2.16×103 L/mol。当PAA加入到SPI／淀粉溶液，不仅会导致体系最大荧光发射波长和荧光强度的变化，而且也产生一个较为明显的荧光等同发射点，这表明三者之间形成了一个新的三元复合物。UV 和RLS的实验结果也说明了淀粉、聚丙烯酸以及大豆蛋白是形成三元复合物的基本结构单元，并通过彼此间的相互作用结合在一起。此外，通过RLS技术研究了三元复合物的热稳定性，并基于RLS数据计算了其热降解动力学参数，从而进一步证实了三元复合物的形成以及PAA在三元复合物形成过程的作用。

Spectroscopic Study of the Formation of Ternary Complex, Starch/Soy Protein Isolate/Polyacrylic Acid

The formation process of a non-covalent ternary complex comprising soy protein isolate (SPI), soluble starch, and polyacrylic acid (PAA) in aqueous solution was studied based on fluorescence, ultraviolet (UV) absorption, and resonance light scattering (RLS) spectra and the thermal stability of the complex was also investigated. The fluorescence results indicated that SPI and starch could interact with PAA, and the corresponding apparent binding constants were 2.02×105 L/mol and 2.16×103 L/mol, respectively. The addition of PAA to SPI/starch solution not only resulted in changes of fluorescence intensity and the maximum emission wavelength but also generated an apparent common fluorescence emission wavelength, which demonstrated the formation of a new ternary complex. UV and RLS experiments indicated that SPI, starch, and PAA were the basic structural units to produce the ternary complex, and were conjugated through interactions among each other. Moreover, the thermal stability of the ternary complex was investigated by RLS technology and the corresponding kinetic parameters of thermal degradation were calculated based on RLS data, thereby confirming the formation of the ternary complex and the role of PAA in the process of complex formation.