DENSITY, THERMAL EXPANSIVITY, VISCOSITY AND REFRACTIVE-INDEX OF LYSOZYME SOLUTIONS AT CRYSTAL-GROWTH CONCENTRATIONS

Lysozyme has been widely used as a model system for nucleation and cry stal growth studies of globular proteins. Yet, few of the properties o f lysozyme solutions, which are needed for interpreting the results of such studies, are known. We have investigated the dependence of the d ensity, thermal expansivity, viscosity and refractive index of lysozym e solutions on protein concentration and temperature at various pH val ues and sodium chloride concentrations. Extensive data are presented i n the form of tables and equations. In particular, we found that the s olution volumes varied as T3/2. This behavior, which appears to be cha racteristic for a large class of liquids, suggests that thermal expans ion is dominantly due to translational motion.