Impact of polymer shell on the formation and time evolution of nanoparticle–protein corona

The study of protein corona formation on nanoparticles (NPs) represents an actual main issue in colloidal, biomedical and toxicological sciences. However, little is known about the influence of polymer shells on the formation and time evolution of protein corona onto functionalized NPs. Therefore, silica-poly(ethylene glycol) core–shell nanohybrids (SNPs@PEG) with different polymer molecular weights (MW) were synthesized and exhaustively characterized. Bovine serum albumin (BSA) at different concentrations (0.1–6 wt%) was used as model protein to study protein corona formation and time evolution. For pristine SNPs and SNPs@PEG (MW = 350 g/mol), zeta potential at different incubation times show a dynamical evolution of the nanoparticle–protein corona. Oppositely, for SNPs@PEG with MW ≥ 2000 g/mol a significant suppression of corona formation and time evolution was observed. Furthermore, AFM investigations suggest a different orientation (side-chain or perpendicular) and penetration depth of BSA toward PEGylated surfaces depending on the polymer length which may explain differences in protein corona evolution.

Graphical abstractFigure optionsDownload full-size imageDownload as PowerPoint slideHighlights► A new synthetic route to pegylated silica nanoparticles with detectable leaving groups was designed for this paper. ► Adsorption of BSA onto pristine silica and pegylated silica have been scrutinized. ► For pristine silica and short-chain pegylated silica (MW = 350 g/mol), a dynamical evolution of the nanoparticle–protein corona is observed. ► For large-chain pegylated silica (MW ≥ 2000 g/mol) a significant suppression of protein corona formation and time evolution is observed. ► AFM investigations suggest a different penetration depth of BSA toward flat surfaces depending on the polymer length.