Nanoscience: Dynamic Light Scattering (DLS)

Brookhaven ZetaPlus with PALS

The ZetaPlus Analyzer relies on dynamic light scattering to measure the size distribution of particles suspended in a given solution based on fluctuations in the scattering intensity (i.e. measurement based on the diffusion rate since small particles move quickly leading to more rapid fluctuations than large particles). The zeta potential, or electrical potential of the interfacial double layer, is a key indicator of the stability of colloidal suspensions. For Example: ζ < ± 5 mV will rapidly aggregate; ζ of ± 20 mV remain unstable; ζ of ± 40 mV show moderate to good stability; and ζ > ±60 mV show virtually no aggregation in solution (i.e. long shelf life).

Cary Eclipse Fluorescence Spectrophotometer


  • Unimodal and multimodal particle size distributions
  • Particle sizing from 3 Å up to 6 μm
  • Zeta Potential at 15o & Particle Sizing at 90o
  • Zeta potentials ranging from -220 mV to 220 mV
  • Temperature control from -5 oC to 110oC
  • Equipped with 35 mW laser (657 nm) and Avalanche Photodiode
  • No Alignment or Calibration Necessary
  • Temperature Ranges from -5C to 110oC


  • Liposomes and Biocolloids
  • Ceramics and Refractories
  • Pigments and inks
  • Pharmaceuticals
  • Emulsions (food, cosmetics, industry, etc.)
  • Monitoring Wastewater Treatment
  • Latexes and other Polymers
  • Carbon Black
  • Nanoparticles


DLS measurement of uniform 400-nm spherical polystyrene particles in suspended in water

DLS measurements obtained for a colloidal suspension of citrate-capped gold nanoparticles in water.

Zeta Potential of colloidal gold particles with a diameter of 30 nm.