The effect of bovine serum albumin on the binding constant and stoichiometry of biocompatible magnetic fluids

In this work, we investigated the interaction between different molecular-coated magnetite nanoparticles and the serum albumin protein. The investigation was based on the fluorescence quenching of the tryptophan residue of the serum albumin protein after the binding with the molecular-coated magnetite nanoparticles to specific sites. Three different biocompatible magnetic fluid samples based on magnetite nanoparticles surface-coated with carboxymethyldextran, tartrate, and polyaspartic were used. Significant differences in the values of binding constant (K_b) and stoichiometry (n) were found as the surface-coating species are changed. The results obtained from the molecular-coated magnetite nanoparticles having different coatings indicate the effect of the coating material in the biological association of magnetite nanoparticles to biological macromolecules.