Protein Corona Composition of Silica Nanoparticles in Complex Media: Nanoparticle Size does not Matter

Abstract

Biomolecules, and particularly proteins, bind on nanoparticle (NP) surfaces to form the so-called protein corona. It is accepted that the corona drives the biological distribution and toxicity of NPs. Here, the corona composition and structure were studied using silica nanoparticles (SiNPs) of different sizes interacting with soluble yeast protein extracts. Adsorption isotherms showed that the amount of adsorbed proteins varied greatly upon NP size with large NPs having more adsorbed proteins per surface unit. The protein corona composition was studied using a large-scale label-free proteomic approach, combined with statistical and regression analyses. Most of the proteins adsorbed on the NPs were the same, regardless of the size of the NPs. To go beyond, the protein physicochemical parameters relevant for the adsorption were studied: electrostatic interactions and disordered regions are the main driving forces for the adsorption on SiNPs but polypeptide sequence length seems to be an important factor as well. This article demonstrates that curvature effects exhibited using model proteins are not determining factors for the corona composition on SiNPs, when dealing with complex biological media.

The nanotopography of SiO2particles impacts the selectivity and 3D fold of bound allergens

“… 52 It was previously demonstrated that binding selectivity in SiO 2 NPs was independent of their particle size. 53 These findings strengthen the hypothesis that the nanotopography parameters studied herein may play a dominant role in the selective binding of protein during the formation of a corona. In the context of interaction with blood plasma proteins, the binding selectivity of NPs has been previously demonstrated, where blood-circulating lipid-based NPs displayed a protein pattern differing from that found in blood plasma without NPs.…”

From Protein Corona to Colloidal Self-Assembly: The Importance of Protein Size in Protein–Nanoparticle Interactions

“…On the contrary, proteins with a strong internal stability (“hard proteins”) tend not to contribute to adsorption and, when they do, not to undergo any significant structural rearrangements. In more recent years, statistical comparative analyses ,, revealed that the main physicochemical factors relevant to protein adsorption on silica NPs include (i) an enrichment in positively charged amino acids, particularly in arginine residues (forming electrostatic interactions with the negatively charged silica surface), and (ii) an enrichment in disordered regions and conversely a depletion in structured regions, confirming the hard/soft protein paradigm in the case of silica NPs.…”

“…A recent report established a comprehensive list of factors that have been shown to govern protein adsorption on NPs . These factors are linked to the intrinsic properties of the NPs, the adsorbed proteins, and the characteristics of their suspending medium, drawing the three sides of the nanobio interface triangle. − Among all of these physicochemical factors, some have been extensively studied, such as the size/curvature effect of NPs, − the physicochemical properties of protein sequences, − and the pH effect of the surrounding environment. − Others have not been as thoroughly examined but may prove crucial under specific conditions (e.g., NP roughness, dynamic flow, and temperature). − …”

In vivo protein corona on nanoparticles: does the control of all material parameters orient the biological behavior?

“…Conclusively, NPs surface curvature strongly affects the protein adsorption as protein-binding affinities are different for the bulk material and NPs surface. Thus, corona formed on NPs made of the same material differ in composition 57 . Undoubtedly, PC formation is a continuous process with changes in PC composition with time due to the motion of already adsorbed proteins which may be replaced by other proteins having stronger binding affinities until the process reaches an equilibrium which is known as the "Vroman effect" 58 .…”