Particles scatter light, this is a fundamental fact and something we all encounter on a daily basis, the sky is blue. This is caused by stronger light scattering of blue light by atmospheric particles than red light. The surface finish be it glossy or matt is caused by the particles in the surface. 

The angle of light scatter, the frequency of the light scattering and the intensity of said scatter can be measured to determine the size, the charge and the molecular weight of materials. This is the core of many of our technologies.

For laser diffraction and X-ray diffraction (small angle X-ray diffraction (SAX), wide angle X-ray diffraction (WAX)), we harness the principle that particles of different sizes have a unique light scattering signature, so by accurately measuring the light scattering over a wide range of angles with high sensitivity and at extremely rapidly we can determine the particle / droplet size of powders, emulsions, sprays and suspensions. However, as particles get substantially into the nanometre range there is a big fall off in how particles scatter light. A 10 nm particle scatters 1 million times less than a 100nm particle, so there is a point at which even by reducing the wavelength of the light source (which increases the amount of scatter) that the light scattering is best analysed in alternate ways. There are multiple theories which can determine the light scattering from a particle size distribution (Mie scattering theory, Fraunhofer scattering theory, Rayleigh scattering theory), and an inversion algorithm can turn scattering into a size distribution.

We can look at the nano material at right angles to the laser and track how the particles diffuse (small particles move more rapidly than large particles) and from this determine the translational diffusion coefficient and hence the size (this is known as nanoparticle tracking analysis (NTA) ) or see how the scattered light changes over time as particles pass through it. If it changes quickly it can be determined that fine particles are present, slowly larger particles. This forms the basis of photon correlation spectroscopy / dynamic light scattering.

Electrophoretic light scattering involves passing an electric field through a liquid which makes particles move. The larger the charge on the particles, the faster they move. We pass a laser though the particles and then recombine the scattered light with another part of the same laser which hasn’t been scattered. The resulting interference pattern allows an incredibly accurate measure of the speed of the particles to be measured.

If we measure the light scattering as a function of concentration (of polymers or biopolymers) at a variety of angles we can determine information that allows us to determine the molecular weight of the material in question and information on its structure.

Mastersizer range

Mastersizer range

World's most popular particle size analyzers

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Measurement Particle size
Particle size range 0.01µm - 3500µm
Technology Light Scattering, Laser Diffraction
Dispersion type Wet, Dry, Wet and Dry

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

Spraytec

Spraytec

Spray particle and spray droplet size measurement

More details
Measurement Particle size
Particle size range 0.1µm - 2000µm
Technology Light Scattering, Laser Diffraction
Dispersion type Dry, Spray

OMNISEC

OMNISEC

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

More details
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

Insitec range

Insitec range

Robust, reliable, real-time particle sizing

More details
Measurement Particle size
Particle size range 0.1µm - 2500µm
Technology Light Scattering, Laser Diffraction
Dispersion type Wet, Dry, Spray, Wet and Dry

Mastersizer range

Mastersizer range

World's most popular particle size analyzers

Zetasizer range

Zetasizer range

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

Spraytec

Spraytec

Spray particle and spray droplet size measurement

OMNISEC

OMNISEC

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

Insitec range

Insitec range

Robust, reliable, real-time particle sizing

More details More details More details More details More details
Measurement Particle size Molecular size, Molecular weight, Particle size, Zeta potential Particle size Molecular structure, Molecular size, Molecular weight, Viscosity, Protein aggregation Particle size
Particle size range 0.01µm - 3500µm 0.3nm - 10µm 0.1µm - 2000µm   0.1µm - 2500µm
Temperature range   0°C - 120°C      
Molecular weight range       200Da - 10MDa  
Minimum sample mass (polystyrene)       100ng  
Minimum sample mass (BSA)       100ng  
Technology Light Scattering, Laser Diffraction Light Scattering, Dynamic Light Scattering, Electrophoretic Light Scattering, Static Light Scattering Light Scattering, Laser Diffraction Gel Permeation Chromatography, Size Exclusion Chromatography (SEC), Light Scattering, Static Light Scattering Light Scattering, Laser Diffraction
Dispersion type Wet, Dry, Wet and Dry Wet Dry, Spray   Wet, Dry, Spray, Wet and Dry
Sample cell type   Cuvette      
Molecular measurement type   Chromotography, Batch measurement      

Mastersizer range

Zetasizer range

Spraytec

OMNISEC

Insitec range

Mastersizer range Zetasizer range Spraytec OMNISEC Insitec range

World's most popular particle size analyzers

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

Spray particle and spray droplet size measurement

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

Robust, reliable, real-time particle sizing

More details More details More details More details More details
Technology
Light Scattering
Laser Diffraction
Dynamic Light Scattering
Electrophoretic Light Scattering
Static Light Scattering
Measurement type
Particle size
Molecular size
Molecular weight
Zeta potential
Molecular structure
Protein aggregation