title: Stabilization of TiO2 nanoparticles in complex medium through a pH adjustment protocol.
abstract: Preparing TiO(2) nanoparticle (NP) suspensions displaying well-defined and reproducible dispersion state is a key feature to perform relevant toxicity experiments for environmental, animal, or human concerns. Relying on the evolution of surface charge with pH, and interactions between nanoparticles in their medium, we developed an optimized dispersion protocol involving a pH adjustment before addition of bovine serum albumin (BSA). It yielded highly dispersed and stable concentrated stock suspensions of TiO(2) NP at pH 7. It was designed for four kinds of manufactured TiO(2) nanomaterials and can be extended to a wide range of TiO(2) NP. The suspensions studied here were characterized by small-angle X-ray scattering (SAXS), using a model quantitatively describing fractal aggregates. Results were correlated with dynamic light scattering (DLS) measurements. Moreover, the stability in a typical biological medium was assessed by diluting stock suspensions in Luria-Bertani (LB) medium. It resulted in highly dispersed and stable working suspensions. No sedimentation, followed by in situ DLS, was observed over 17 h for both the concentrated stock suspensions prepared according to the pH adjusted-BSA protocol and their dilution into LB medium.
authors.affiliation: CEA Saclay, DSM/IRAMIS/SIS2M/LIONS UMR3299, 91191 Gif-sur Yvette, France.
authors.forename: Camille
authors.initials: C
authors.lastname: Guiot
authors.forename: Olivier
authors.initials: O
authors.lastname: Spalla
mesh_terms: D000818:Animals; D002417:Cattle; D006863:Hydrogen-Ion Concentration; D053758:Nanoparticles / Q000737:chemistry*; D010316:Particle Size; D053838:Scattering, Small Angle; D012710:Serum Albumin, Bovine / Q000737:chemistry*; D013499:Surface Properties; D014025:Titanium / Q000737:chemistry*; D014961:X-Ray Diffraction
chemical_list: C009495:titanium dioxide; D012710:Serum Albumin, Bovine; D014025:Titanium