Identification of factors affecting physicochemical fate of metallic - PowerPoint PPT Presentation

PhD Research Identification of factors affecting physicochemical fate of metallic nanoparticles in aquatic environments Frederik Van Koetsem Ghent, 24 February 2011 Promotor: Prof. Gijs Du Laing

Introduction In 1. . Met etall llic en engin ineered nan anopartic icles (E (ENPs)  Ultrafine particles (1 – 100 nm) containing metals Fig. Ag Nanoparticles Fig. ZnO Nanoparticles Fig. Au Nanoparticles  Can exhibit size-related properties  Potential adverse effects on humans & ecosystems 2 Frederik Van Koetsem – Laboratory of Analytical Chemistry and Applied Ecochemistry – 24 February 2011

In Introduction 2. . Applic icati tions of of meta etallic ENPs 3 Frederik Van Koetsem – Laboratory of Analytical Chemistry and Applied Ecochemistry – 24 February 2011

Aim im  To contribute to the identification of factors affecting the fate of metallic ENPs  To reveal the kinetics of NPs’ transformation processes  To study environmental factors affecting remobilization of adsorbed or precipitated metallic ENPs  To aid in the development of analytical methods to quantify metallic ENPs of different sizes 4 Frederik Van Koetsem – Laboratory of Analytical Chemistry and Applied Ecochemistry – 24 February 2011

Analy lytical method development  Recently, coupling of chromatographic techniques to an element specific detector as ICP-MS, e.g.:  RPC-ICP-MS  SEC-ICP-MS  FFF-ICP-MS  Focus ⇨ optimization of existing analytical procedures  HDC ⇨ separation of particulate matter of ≠ sizes  ICP-MS ⇨ measurement of metal content 5 Frederik Van Koetsem – Laboratory of Analytical Chemistry and Applied Ecochemistry – 24 February 2011

Analy lytical method development  Current lab set-up ⇨ HPLC -ICP-MS hyphenated system  Size calibration with Au NPs  Method validation & additional analysis @ external labs  EM techniques (e.g., TEM, SEM)  DLS  ζ -potential measurements  BET  Etc. HD HDC 6 Frederik Van Koetsem – Laboratory of Analytical Chemistry and Applied Ecochemistry – 24 February 2011

Aim im  To contribute to the identification of factors affecting the fate of metallic ENPs  To reveal the kinetics of NPs’ transformation processes  To study environmental factors affecting remobilization of adsorbed or precipitated metallic ENPs  To aid in the development of analytical methods to quantify metallic ENPs of different sizes 7 Frederik Van Koetsem – Laboratory of Analytical Chemistry and Applied Ecochemistry – 24 February 2011

Fate of f ENPs re rele leased in into aquatic environments 1. . Phy hysicochemical be behavio ior of of meta etallic ENPs  Widespread use of NMs in consumer products ⇨ rel elease in in aq aquati tic, ter terrestr trial, , an and atm atmospheric en envir ironments 8 Frederik Van Koetsem – Laboratory of Analytical Chemistry and Applied Ecochemistry – 24 February 2011

Fate of f ENPs re rele leased in into aquatic environments  ENPs’ unique properties ⇨ unexpected health and/or environmental hazards  Few studies ⇰ Strong need for complete life cycle analysis of of the the fat fate and tra an transport t of of ENPs in in the the en envir ironment  Exposure to ENPs determined by kinetics of several physicochemical transformation processes 9 Frederik Van Koetsem – Laboratory of Analytical Chemistry and Applied Ecochemistry – 24 February 2011

Fate of f ENPs re rele leased in into aquatic environments  ENPs colloidal stability and mobility, NP sorption, or aggregation and deposition ⇨ f(ENP surface properties)  ENP surface properties dependant on, e.g.:  Temperature  Ionic strength  pH  Particle concentration and size  Redox reactions and/or association with NOM or surfactants ⇨ increasing complexity of interactions 10 Frederik Van Koetsem – Laboratory of Analytical Chemistry and Applied Ecochemistry – 24 February 2011

Fate of f ENPs re rele leased in into aquatic environments 2. . Exp xperim imenta tal pr prospect  Collection of different aquatic samples, e.g.:  ≠ pH, ≠ salinity, ≠ OM content, ≠ redox potential  Spiking with metallic ENPs  Analysis via developed analytical toolbox  Additional monitoring of physicochemical characteristics  Electrical conductivity, pH, redox potential, etc.  Behavior ENPs ⇔ characteristics of aquatic samples ⇰ id identif ificati tion of of pa paramete ters affe affecti ting fate fate of of ENPs in in rea eal en envir ironmental sa samples 11 Frederik Van Koetsem – Laboratory of Analytical Chemistry and Applied Ecochemistry – 24 February 2011

Aim im  To contribute to the identification of factors affecting the fate of metallic ENPs  To reveal the kinetics of NPs’ transformation processes  To study environmental factors affecting remobilization of adsorbed or precipitated metallic ENPs  To aid in the development of analytical methods to quantify metallic ENPs of different sizes 12 Frederik Van Koetsem – Laboratory of Analytical Chemistry and Applied Ecochemistry – 24 February 2011

Kin inetics of f tra ransformation & re remobilization of f ENPs  Environmental changes ⇨ transformation or remobilization of metallic ENP  Changing environmental conditions ⇨ study the kinetics of processes affecting NP distribution  Mimicking of these alterations via 16 Microcosm set-ups (developed by Prof. J Rinklebe) 13 Frederik Van Koetsem – Laboratory of Analytical Chemistry and Applied Ecochemistry – 24 February 2011

Kin inetics of f tra ransformation & re remobilization of f ENPs Microcosm set-up 14 Frederik Van Koetsem – Laboratory of Analytical Chemistry and Applied Ecochemistry – 24 February 2011

Thank you fo for your attention Any questions? 15 Frederik Van Koetsem – Laboratory of Analytical Chemistry and Applied Ecochemistry – 24 February 2011