The Effect of Protein Corona on Gold Nanoparticles Aggregation

Abstract: Nanoparticles (NPs) are the particles between 1 and 100 nm. They are widely used in the medical field as delivery vehicles, therapeutics and contrast agents in cancer diagnosis and treatment. There are different types of NPs divided according to the source of used materials. The agglomeration of NPs can be prevented by adding different polymers to their surfaces. The optical properties of gold nanoparticles (GNPs) make them a good system for following the behaviour of NPs in vivo. The surface properties are determined according to the purpose and type of the target. The protein layers covering GNPs is called corona. The composition of corona depends on the particle material, size and surface properties. In this study, different methods (DLS, disc centrifuge and SDS-PAGE) were used to investigate the effect of different proteins, including PGB1, IgG and plasma proteins (cow and calf) on the aggregation of GNPs and how these aggregations could be prevented. It was found that PGB1 did not aggregate the particles while IgG did and the amount of aggregation depends on IgG concentration. In addition, PBS aggregated the particles while the water stabilized them. Finally, some experiments were done on carboxylated and biotinylated GNPs trying to conjugate to PGB1 and streptavidin respectively, but the results were unclear and more studies are needed.