Particle Sizing by Dynamic Light Scattering (DLS)
Dynamic Light Scattering (DLS) technique is the perfect choice to characterize nano- and
microparticles at the touch of a button. Particles in dispersion as well as peptides or
macromolecules in solution can be determined over a broad concentration range with minimal
sample preparation. Litesizer 500 includes three measurement angles for measuring the
particle size and particle size distribution of the colloidal samples.
Particles suspended in a liquid are constantly undergoing random motion, and the size of the
particles directly affects their speed. Smaller particles move faster than larger ones. In dynamic
light scattering (DLS), light passes through the sample, and the scattered light is detected and
recorded at a certain angle. The time dependence of the scattered intensity reveals how fast
the particles are moving. From this information, it’s possible to calculate the average size of the
particles as well as the size distribution.
PARTICLE SIZE SPECIFICATIONS
Measuring range: 0.3 nm to 10 μm
Sensitivity: 0.1 mg/mL (lysozyme)
Max. sample concentration: 50 % w/v (sample-dependent)
Accuracy: Better than ±2 % on NIST traceable standards
Repeatability: Better than ±2 % on NIST traceable standards
Min. sample volume: 12 μL
Measurement angles: 15°, 90°, 175°
Zeta Potential Analysis by Electrophoretic Light Scattering (ELS)
Litesizer 500 can also determine the zeta potential of colloidal samples at low voltages with the
highest repeatability and accuracy using the electrophoretic light scattering (ELS) technique
thanks to the Anton Paar’s patented cmPALS technology. In ELS, the speed of the
particles is measured in the presence of an electric field. The faster the particles move, the
higher the zeta potential of the particles are. In general, a greater-magnitude zeta potential
means that the particles will repel each other more strongly, giving a more stable suspension or
emulsion.
ZETA POTENTIAL SPECIFICATIONS
Measuring range: > ±1000 mV
Particle size range: 3.8 nm to 100 μm
Sensitivity: 0.1 mg/mL (lysozyme)
Repeatability: ± 3 %
Max. sample concentration: 70 % w/v (sample-dependent)
Sample volume: 50 μL (sample viscosity dependent)
Max. sample conductivity: 200 mS/cm
Measurement angle: 15°
pH range: 2 to 12
Light Transmittance by Light Permeability
Litesizer 500 measures the light transmittance getting through your samples constantly in the
background which gives you instant feedback about your sample turbidity, concentration as
well as stability.
Transmittance is measured by detecting the fraction of light that passes through the sample.
The Litesizer 500 particle analyzer continuously measures the transmittance for every sample.
The value is reported in real time and is displayed during operation.
TRANSMITTANCE SPECIFICATIONS
Measuring time: 10 s
Min. sample volume: 15 μL
All results are compiled into a comprehensive report. Reports will include the particle size or
the zeta potential distribution, statistics of the particle size, polydispersity index as well as zeta
potential value.
