BSA, zeta potential

After measurement it is obvious that zeta potential depends on all of these parameters. At low pH, BSA generally presented positive zeta potentials which decreased when pH was raised. The isoelectric point of BSA was found between values pH 4.5 ? 5.0. Zeta potential increases when temperature increases. Higher temperature can cause conformal changes. Different concentration of BSA has a small effect on zeta potential. In terms of time, the system of BSA solution is unstable and it changes dynamically. In presence of KCl in solution zeta potential of BSA is lower in compares with BSA in distilled water. As mentioned above all parameters influence zeta potential of BSA.

Adsorption of BSA on nanoceria can be described by Langmuir adsorption theory, using linear regression were calculated maximum adsorption capacities. Thus, the equilibrium constant of adsorption could be calculated from the Langmuir binding constant b. It was proved that the adsorption capacity of BSA on nanoceria particles increased (for pH 4) with a rise in temperature. Calculated thermodynamic parameters indicate that the adsorption of BSA on the ceria is endothermic (?Hads > 0) and non-spontaneous (?Gads > 0) process. The kinetics of adsorption fitted best to pseudo-second-order. Further measurement is necessary to explain the mechanism of BSA adsorption on NPs.