A systematic evaluation of agglomeration of Ag and TiO2 nanoparticles under freshwater relevant conditions.

A systematic evaluation of agglomeration of Ag and TiO2 nanoparticles under freshwater relevant conditions.

Environmental pollution (Barking, Essex : 1987) (2014-07-08)

Emel Topuz, Laura Sigg, Ilhan Talinli

ZUSAMMENFASSUNG

This study aims to investigate effects of freshwater components in order to predict agglomeration behavior of silver nanoparticles coated with citrate (AgNP-Cit), polyvinylpyrrolidone (AgNP-PVP), and of TiO2 nanoparticles. Agglomeration studies were conducted in various media based on combinations of ions, natural organic matter (humic, fulvic acid) and surfactants (sodium dodecyl sulfate, alkyl ethoxylate), at a constant ionic strength of 10 mM over time for up to 1 week. Agglomeration level of AgNP-Cit and TiO2 was mostly dependent on the concentration of Ca(2+) in media, and their size strongly increased to micrometer scale over 1 week. However, AgNP-Cit and TiO2 were stabilized to particle size around 500 nm in the presence of NOM, surfactants and carbonate over 1 week. AgNP-PVP maintained their original size in all media except in the presence of Mg(2+) ions which led to significant agglomeration. Behavior of these engineered nanoparticles was similar in a natural freshwater medium.

MATERIALIEN

Produktnummer

Marke

Produktbeschreibung

27109

Sigma-Aldrich

Zitronensäure, meets analytical specification of Ph. Eur., BP, USP, E330, anhydrous, 99.5-100.5% (based on anhydrous substance)

PVP360

Sigma-Aldrich

Polyvinylpyrrolidon, mol wt (number average molecular weight Mn 360kDa)

718467

Sigma-Aldrich

Titan(IV)-oxid, nanopowder, 21 nm primary particle size (TEM), ≥99.5% trace metals basis

437190

Sigma-Aldrich

Polyvinylpyrrolidon, average M_w ~1,300,000 by LS

637254

Sigma-Aldrich

Titan(IV)-oxid, Anatase, nanopowder, <25 nm particle size, 99.7% trace metals basis

PVP40

Sigma-Aldrich

Polyvinylpyrrolidon, average mol wt 40,000

856568

Sigma-Aldrich

Polyvinylpyrrolidon, powder, average M_w ~55,000

735825

Sigma-Aldrich

Silber, conductive paste

232033

Sigma-Aldrich

Titan(IV)-oxid, Anatase, powder, 99.8% trace metals basis

14021

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Titan(IV)-oxid, ReagentPlus^®, ≥99%

251275

Sigma-Aldrich

Zitronensäure, ACS reagent, ≥99.5%

234257

Sigma-Aldrich

Polyvinylpyrrolidon, powder, average M_w ~29,000

224227

Sigma-Aldrich

Titan(IV)-oxid, Rutil, powder, <5 μm, ≥99.9% trace metals basis

P0930

Sigma-Aldrich

Polyvinylpyrrolidon, powder, BioXtra, suitable for mouse embryo cell culture

W230618

Sigma-Aldrich

Zitronensäure, ≥99.5%, FCC, FG

248576

Sigma-Aldrich

Titan(IV)-oxid, Anatase, powder, −325 mesh, ≥99% trace metals basis

C2404

Sigma-Aldrich

Zitronensäure, anhydrous, suitable for cell culture, suitable for plant cell culture

637262

Sigma-Aldrich

Titan(IV)-oxid, Rutil, nanopowder, <100 nm particle size, 99.5% trace metals basis

1134368

USP

Zitronensäure, United States Pharmacopeia (USP) Reference Standard

634662

Sigma-Aldrich

Titan(IV)-oxid, Mischung aus Rutil und Anatas, nanopowder, <100 nm particle size (BET), 99.5% trace metals basis

27487

Sigma-Aldrich

Zitronensäure, BioUltra, anhydrous, ≥99.5% (T)

C0759

Sigma-Aldrich

Zitronensäure, 99%

348791

Sigma-Aldrich

Titan, foil, thickness 0.127 mm, 99.7% trace metals basis

81420

Sigma-Aldrich

Polyvinylpyrrolidon, K 30

366994

Sigma-Aldrich

Titan, powder, <45 μm avg. part. size, 99.98% trace metals basis

739421

Sigma-Aldrich

Silber-Nanodrähte, diam. × L 50 nm × 6 μm, 0.5% (isopropyl alcohol suspension)

267503

Sigma-Aldrich

Titan, foil, thickness 0.25 mm, 99.7% trace metals basis

700347

Sigma-Aldrich

Titan(IV)-oxid, Mischung aus Rutil und Anatas, nanoparticles, <150 nm particle size (volume distribution, DLS), dispersion, 40 wt. % in H₂O, 99.5% trace metals basis

PVP10

Sigma-Aldrich

Polyvinylpyrrolidon, average mol wt 10,000

02286

Sigma-Aldrich

Kollidon^® 25