Quantification of the PEGylated Gold Nanoparticles Protein Corona. Influence on Nanoparticle Size and Surface Chemistry

<jats:p>The interactions of nanoparticles with living organisms are driven by an interface called the protein corona. This interface is formed when nanoparticles are introduced in biological milieu and proteins are adsorbed at nanoparticles’ surfaces. Understanding the factors that are responsible for the formation and the composition of the protein corona could reveal mechanistic insights that are involved in the interaction of nanoparticles with biological structures. Multiple studies have qualitatively described the protein corona, but just a few have proposed quantification methods, especially for gold nanoparticles. Using bovine serum albumin conjugated with fluorescein-5-isothiocyanate as a model protein, we developed a fluorescent-based quantification method for gold nanoparticles’ protein coronas. The impact of nanoparticle size and surface chemistry was studied, and our research emphasizes that size and surface chemistry are determinant factors: Bigger nanoparticles and amino-modified surface chemistry are responsible for higher protein adsorption compared to smaller ones and carboxyl- or methoxy-modified surface chemistry. The proposed method can be used to complete the full picture of the interactions of nanoparticles with biological milieu and to describe the parameters which govern these interactions for the better development of nanomedicines.</jats:p>