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, silicapoly(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.
Synthesis and characterisation of highly fluorescent core-shell nanoparticles based on Alexa dyes
(2012)
Current and future developments in the
emerging field of nanobiotechnology are closely
linked to the rational design of novel fluorescent
nanomaterials, e.g. for biosensing and imaging applications.
Here, the synthesis of bright near infrared
(NIR)-emissive nanoparticles based on the grafting
of silica nanoparticles (SNPs) with 3-aminopropyl
triethoxysilane (APTES) followed by covalent attachment
of Alexa dyes and their subsequent shielding by an
additional silica shell are presented. These nanoparticles
were investigated by dynamic light scattering (DLS),
transmission electron microscopy (TEM) and fluorescence
spectroscopy. TEM studies revealed the monodispersity
of the initially prepared and fluorophorelabelled
silica particles and the subsequent formation of
raspberry-like structures after addition of a silica
precursor.Measurements of absolute fluorescence quantum
yields of these scattering particle suspensions with
an integrating sphere setup demonstrated the influence
of dye labelling density-dependent fluorophore aggregation
on the signaling behaviour of such nanoparticles.