Static light scattering (SLS) is a technique to measure absolute molecular weight using the relationship between the intensity of light scattered by a molecule and its molecular weight and size, as described by the Rayleigh theory. In the simplest terms, Rayleigh theory says that larger molecules scatter more light than smaller molecules from a given light source and that the intensity of the scattered light is proportional to the molecule’s molecular weight.

There are two ways to measure absolute molecular weight by static light scattering:

  1. Batch measurement using a cuvette
  2. In combination with a chromatography instrument.

Batch measurement with cuvette based instruments, such as the Zetasizer series, is an ensemble technique. Therefore the result calculated is the weight average molecular weight of the entire sample measured.

However, the most common way of measuring absolute molecular weight is to add an SLS detector e.g. Low Angle Light Scattering LALS, Right Angle Light Scattering RALS or Multi Angle Light Scattering MALS to a GPC/SEC system. By combining SLS with the separation technique you can calculate the absolute molecular weight at any point in the eluting chromatogram and determining the molecular weight of any population in a mixed sample becomes possible.

OMNISEC

OMNISEC

The world’s most advanced multi-detector GPC/SEC system

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Measurement Molecular structure, Molecular size, Molecular weight, Viscosity, Protein aggregation
Molecular weight range 200Da - 10MDa
Minimum sample mass (polystyrene) 100ng
Minimum sample mass (BSA) 100ng
Technology Gel Permeation Chromatography, Size Exclusion Chromatography (SEC), Light Scattering, Static Light Scattering

Zetasizer range

Zetasizer range

The world’s most widely-used systems for nanoparticle, colloid and biomolecular particle sizing and particle charge measurements

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Measurement Molecular size, Molecular weight, Particle size, Zeta potential
Temperature range 0°C - 120°C
Particle size range 0.3nm - 10µm
Technology Light Scattering, Dynamic Light Scattering, Electrophoretic Light Scattering, Static Light Scattering
Dispersion type Wet
Sample cell type Cuvette
Molecular measurement type Chromotography, Batch measurement

OMNISEC

OMNISEC

The world’s most advanced multi-detector GPC/SEC system

Zetasizer range

Zetasizer range

The world’s most widely-used systems for nanoparticle, colloid and biomolecular particle sizing and particle charge measurements

More details More details
Measurement Molecular structure, Molecular size, Molecular weight, Viscosity, Protein aggregation Molecular size, Molecular weight, Particle size, Zeta potential
Molecular weight range 200Da - 10MDa  
Minimum sample mass (polystyrene) 100ng  
Minimum sample mass (BSA) 100ng  
Temperature range   0°C - 120°C
Particle size range   0.3nm - 10µm
Technology Gel Permeation Chromatography, Size Exclusion Chromatography (SEC), Light Scattering, Static Light Scattering Light Scattering, Dynamic Light Scattering, Electrophoretic Light Scattering, Static Light Scattering
Dispersion type   Wet
Sample cell type   Cuvette
Molecular measurement type   Chromotography, Batch measurement

Zetasizer Advance Range

OMNISEC

Zetasizer Advance Range OMNISEC

Light Scattering for every application

The world’s most advanced multi-detector GPC/SEC system

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Technology
Static Light Scattering
Measurement type
Molecular structure
Molecular size
Molecular weight
Protein aggregation
Particle size
Zeta potential