动态光散射测定电介质溶液中蛋白质 HAMAKER常量实验研究

通过动态光散射技术间接的测量了电介质溶液中蛋白质的Hamaker常量.溶液中粒子的扩散系数对浓度的一阶线性依赖关系主要取决于粒子在溶液中所占的体积分数和粒子间的排斥力与吸引力.通过动态光散射技术测量不同离子强度不同浓度蛋白分子的扩散系数,根据扩散系数随蛋白浓度变化的斜率与离子浓度变化的相关性,回归出蛋白的Hamaker常量和蛋白的有效电荷.

Dynamic Light Scattering Determination Hamaker Constant of Proteins in Electrolyte Solutions

The van dcr Waals force, which arises from the electrodynamics interactions between oscillating dipoles, is a fundamental interaction of matter. Hamaker constant is an essential parameter Involved and dependents on the polarizability and number density of atoms in the two media. This paper indirectly determinates Hamaker constant of proteins in electrolyte by dynamic light scattering. The concentration dependence of the diffusion coefficient of particles suspended in solution depends primarily on the occupied volume fraction and on repulsive and attractive forces. The diffusion coefficient of proteins has bccn measured in different concentrations and different ionic intensities by dynamic light scattering. Through the correlation between slop of diffusion coefficient verse concentration of proteins and the change of ionic concentration, the Hamakcr constant and effective charge of proteins arc regressed. The results indicate that dynamic light scattering could effectively determinate Hamaker constant of biopolymcr while it is difficult to measure by another technique.