| Abstract: | The complexes formed by the interaction of human serum albumin and ampicillin sodium in aqueous solutions were investigated at 25 ± 0.1°C, ionic strength I = 0.085 mol·kg−1, pH 4.9, 5.8 and 7.4. The results of static light scattering have suggested that at pH 7.4, 5.8, 4.9, the molecular weight of the protein/drug complexes is 210,000 g·mol−1, 418,000 g·mol−1, 448,000 g·mol−1, respectively. The z-average root-mean-square radius of gyration and the second virial coefficients decrease with pH decreasing. Dynamic light scattering provides information on diffusion coefficient and particle distributions of protein/drug complexes under different conditions, which suggests a broad hydrodynamic diameter range of scatters. The diffusion coefficients of the systems change with ampicillin sodium concentration and pH changing. |
