TY - JOUR A1 - Natte, Kishore A1 - Friedrich, Jörg Florian A1 - Wohlrab, Sebastian A1 - Lutzki, J. A1 - von Klitzing, R. A1 - Österle, Werner A1 - Orts-Gil, Guillermo T1 - Impact of polymer shell on the formation and time evolution of nanoparticle-protein corona N2 - 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. KW - Nanoparticles KW - Silica KW - PEGylation KW - Protein corona KW - BSA KW - Biointerface PY - 2013 DO - https://doi.org/10.1016/j.colsurfb.2012.11.019 SN - 0927-7765 VL - 104 SP - 213 EP - 220 PB - Elsevier AN - OPUS4-38547 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Natte, Kishore A1 - Österle, Werner A1 - Friedrich, Jörg Florian A1 - von Klitzing, R. A1 - Orts-Gil, Guillermo T1 - Tuning interfacial properties and colloidal behavior of hybrid nanoparticles by controlling the polymer precursor N2 - A facile and versatile synthetic route for controlling the size and surface potential of organic–inorganic hybrid silica nanoparticles (NPs) is introduced in this paper. For polymer-grafted NPs, the density of polymer chains on the surface is strongly affected by the concentration of precursor. Nevertheless, for condensed NPs, the precursor concentration determines the particle size but not the density of polymer chains on the surface or the adsorption of bovine serum albumin (BSA). Results presented here may have Major implications in biomedical and colloidal chemistry since interfacial and colloidal properties are known to drive several processes associated with nanoparticles in biological media. KW - BSA KW - Bio-interface KW - Nanosilica hybrids KW - PEG KW - Protein corona PY - 2012 DO - https://doi.org/10.1002/macp.201200148 SN - 0025-116X SN - 1022-1352 SN - 1521-3935 VL - 213 IS - 22 SP - 2412 EP - 2419 PB - Whiley-VCH CY - Weinheim AN - OPUS4-38549 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Natte, Kishore A1 - Behnke, Thomas A1 - Orts Gil, Guillermo A1 - Würth, Christian A1 - Friedrich, Jörg Florian A1 - Österle, Werner A1 - Resch-Genger, Ute T1 - Synthesis and characterisation of highly fluorescent core-shell nanoparticles based on Alexa dyes N2 - 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. KW - Silica KW - Alexa dyes KW - Fluorescent particles KW - Quantum yields KW - Nanoparticles KW - Protective shell KW - Nanobiotechnology PY - 2012 DO - https://doi.org/10.1007/s11051-011-0680-9 SN - 1388-0764 SN - 1572-896X VL - 14 IS - 2 SP - 680-1 - 680-10 PB - Kluwer CY - Dordrecht AN - OPUS4-25872 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER -