title: Effect of sonication on particle dispersion, administered dose and metal release of non-functionalized, non-inert metal nanoparticles.
abstract: In this study, we elucidate the effect of different sonication techniques to efficiently prepare particle dispersions from selected non-functionalized NPs (Cu, Al, Mn, ZnO), and corresponding consequences on the particle dose, surface charge and release of metals. Probe sonication was shown to be the preferred method for dispersing non-inert, non-functionalized metal NPs (Cu, Mn, Al). However, rapid sedimentation during sonication resulted in differences between the real and the administered doses in the order of 30-80 % when sonicating in 1 and 2.56 g/L NP stock solutions. After sonication, extensive agglomeration of the metal NPs resulted in rapid sedimentation of all particles. DLVO calculations supported these findings, showing the strong van der Waals forces of the metal NPs to result in significant NP agglomeration. Metal release from the metal NPs was slightly increased by increased sonication. The addition of a stabilizing agent (bovine serum albumin) had an accelerating effect on the release of metals in sonicated solutions. For Cu and Mn NPs, the extent of particle dissolution increased from <1.6 to ~5 % after sonication for 15 min. A prolonged sonication time (3-15 min) had negligible effects on the zeta potential of the studied NPs. In all, it is shown that it is of utmost importance to carefully investigate how sonication influences the physico-chemical properties of dispersed metal NPs. This should be considered in nanotoxicology investigations of metal NPs.
authors: Division of Surface and Corrosion Science, Department of Chemistry, KTH Royal Institute of Technology, Drottning Kristinas väg 51, 100 44 Stockholm, Sweden.
authors: Sulena
authors: S
authors: Pradhan
authors: Division of Surface and Corrosion Science, Department of Chemistry, KTH Royal Institute of Technology, Drottning Kristinas väg 51, 100 44 Stockholm, Sweden.
authors: Jonas
authors: 0000-0003-2100-8864
authors: J
authors: Hedberg
authors: Division of Surface and Corrosion Science, Department of Chemistry, KTH Royal Institute of Technology, Drottning Kristinas väg 51, 100 44 Stockholm, Sweden ; Chemistry, Materials and Surfaces, SP Technical Research Institute of Sweden, P.O. Box 5607, 114 86 Stockholm, Sweden.
authors: Eva
authors: E
authors: Blomberg
authors: Division of Applied Physical Chemistry, Department of Chemistry, KTH Royal Institute of Technology, Drottning Kristinas väg 51, 100 44 Stockholm, Sweden.
authors: Susanna
authors: S
authors: Wold
authors: Division of Surface and Corrosion Science, Department of Chemistry, KTH Royal Institute of Technology, Drottning Kristinas väg 51, 100 44 Stockholm, Sweden.
authors: Inger
authors: I
authors: Odnevall Wallinder
keywords: Aluminium; BSA; Copper; DLVO; Dosimetry; Manganese; Metal release; Nanoparticles; Particle dispersion; Particle size; Sonication; Zeta potential