PROTEIN CORONA OVER POLYMER-COATED GOLD NANOPARTICLES

The unique properties of gold nanoparticles (AuNPs) enable their use for many applications, such as biomedical.¹ The use of polymers allows an interesting route for AuNPs production, enabling a one-pot, simple and fast method, where the polymer chains act as both reducing and stabilizing agents.² For biomedical uses, the behavior of gold nanoparticles in contact with living systems needs further and deeper investigations. Particularly, the development of biomolecular coronas onto surfaces and its biological consequences are still poorly understood.³ In this work, we produced polymer-coated gold nanoparticles from different nitrogen-containing polymers: polyethylenimines, poly(aminoethyl)methacrylates, and polyoxazolines. The AuNPs produced are mostly spherical, with diameters between 4 to 30 nm by TEM, and ζ between +15 to -15 mV, depending on the polymer used. The corona formation is evaluated by surface plasmon resonance (SPR) measured in UV-Vis, and by the hydrodynamic radius (R_H) measured by DLS. The results on SPR and R_H allow us to clearly observe aggregation for AuNPs@BPEI,  AuNPs@BPEI-C₆ and AuNP@BPEI-Man, to differentiate two regimes (no corona aggregation and aggregation) for AuNP-PDMA and AuNP-PDEA, and to infer about the corona formation over AuNP-PMeOx, when incubated with HSA in PB 10 mM pH 7,4. The corona formation will be evaluated with other proteins, such as lysozime, BSA and IgG to determine the influence of polymer surface chemistry on protein adsorption, and the protein corona will be corroborated with SDS-PAGE. This work is expected to lead to significant advances towards the application of AuNPs-polymer composites in therapy and diagnostics.