Specifications

• Model: Zetasizer Nano ZS, Malvern.
• Size range: 0.6nm to 6μm hydrodynamic diameter.
• Size range for Zeta potential: 3nm to 10μm, minimum sample volume: 0.75ml.
• Molecular weight range: 1000 to 2x10^7^ Daltons. Minimum sample volume: 12μl.
• Zeta potential measurements are automated with Autotitrator. Minimum sample volume: 5ml.
• Measurement techniques: (1) Size-Nano ZS: Dynamic light scattering (NIBS), (2) Zeta potential: M3 - PALS, (3) Molecular weight: Static light scattering.
• Laser: Standard - Red He-Ne, 4.0 mW, 633nm.
• Detector: Avalanche photodiode, Q.E. >50% at 633nm.

Principles

The particles are constantly moving due to Brownian motion. Brownian motion is the movement of particles due to the random collision with the molecules of the liquid that surrounds the particle. An important feature of Brownian motion is that small particles move quickly and large particles move more slowly. The relationship between the size of a particle and its speed due to Brownian motion is defined in the Stokes-Einstein equation.

Capabilities

Light scattering equipment is used for the measurement of the size, electrophoretic mobility of proteins, the zeta potential of colloids and nanoparticles. The Zetasizer Nano ZS is a high-performance two-angle particle and molecular size analyzer for the enhanced detection of aggregates and measurement of small or dilute samples, and samples at very low or high concentration using dynamic light scattering with 'NIBS' optics.

Applications

• Particle Size: Colloid size and size distribution, pharmaceuticals, nanoparticles, emulsions.
• Zeta Potential: Emulsion stability, formulation stability, water treatment, pigment performance, and impurity determination.
• Molecular weight: Protein and polymer characteristics, Protein crystal screening, 2^nd^ virial coefficient determination, oligomer identification, protein-melting point, micelle structure, protein-ligand binding.