Nanoparticle Analysis

Nanoparticles and colloids play a pivotal role in many environmental processes, bridging the gap between solutes and solids. Their small size (ranging from 1–1000 nm) results in a large specific surface area, heightened reactivity, rapid particle dynamics, and potential mobility across diverse environments including marine and freshwater systems, groundwater, soils, and sediments. In these settings, pollutants often adsorb to nanoparticle surfaces or co-precipitate during particle formation. Additionally, manufactured nanoparticles themselves may pose as potential environmental pollutants.

Investigating the critical role of nanoparticles and colloids in environmental processes requires specialised instruments and methodologies, beyond the scope of typical environmental chemistry.

Our methods, at a glance

  • Laser-based particle sizing techniques
  • Dynamic light scattering/laser doppler anemometry
  • Field flow fractionation analysis (FFF) including symmetric flow-, asymmetric flow-, hollow fiber and centrifugal FFF
  • Inductively coupled plasma-time of flight mass spectrometry (ICP-TOFMS)

Gold nanoparticles (30 nm) among natural soil-derived nanoparticles in a scanning electron microscope

At CeMESS, we pioneer the development of innovative methods to detect, identify, quantify, and characterize nanoparticles – be they natural, incidental, or manufactured. This involves a multifaceted approach encompassing sampling, sample preparation, and advanced analysis techniques.

We use laser-based particle sizing techniques (based on beam shading, static and dynamic light scattering) to determine particle size distributions from 0.6 nm to 600 µm. This also tells us about the shape and fractal dimension of particles and their aggregates. To investigate the zeta potential and isoelectric point of particles, we use laser doppler anemometry in liquid samples, or determine the streaming potential on surfaces or in porous media.

In our world-leading laboratory for field flow fractionation (FFF) analysis, we operate different instruments (asymmetric flow-, hollow fiber and centrifugal FFF) alongside multi-detection systems. This allows us to separate and size particles in our samples. Our lab also boasts one of the few inductively coupled plasmatime of flight mass spectrometer (ICP-TOFMS) in Austria, operated jointly with the Faculty of Chemistry. This machine collects full elemental spectra for each nanoparticle, surpassing the limitations of standard ICP-MS instruments that may only detect one isotope in a time-resolved mode. With our instrumentation, methodologies and expertise, we shine light into “the world of neglected dimensions” (W. Ostwald).