Dynamic light scattering (DLS) is a technique that can be used to determine the size distribution of small particles in suspension or macromelecules in solution by means of mathematical relations between light scattering and diffusion behaviour of particles.
In the basic setup of a DLS instrument, a single frequency laser is directed to the sample contained in a cuvette. When light hits small particles in random Brownian motion, the light diffuses in all directions and the scattering intensity fluctuates over time. The scattered light is detected at a certain angle over time and this fluctuating signal is used to determine the diffusion behaviour of the particles which derives from an autocorrelation of the intensity trace recorded during the experiment and is directly correlated to the size of the particles (or more precisely to the particles' hydrodynamic radii): bigger particles diffuse slower than smaller ones. The output of a DLS size measurement is a light intensity-based distribution that can be converted to a mass or volume one by means of Mie theory. The main advantage of the technique is the detectable particle size that ranges from less than one nanometer to few microns. Moreover, any surface effect (such as organic coating or electrical charge variation) can be analysed by DLS.
Determination of the size (0.6nm to 6μm) and zeta potential (for particles whose sizes are between 5nm to 10μm) of colloids.
A micro volume (12 µl) quartz cell for DLS and an universal dip cell for the determination of zeta potential in organic solvents are available.
JRC - ISPRA
Italy
DYNAMIC LIGHT SCATTERING
Dynamic light scattering (DLS), is a powerful tool for investigating the diffusion behaviour of macromolecules or particles in suspension. It gives an estimate of the size of the particles by means of mathematical relations between light scattering and diffusion behaviour of particles.
CNR-DSCTM
Italy
DLS at ISSMC (former ISTEC)
TUG
Italy
DLS Instrument Zeta sizer
DLS and Zeta sizer experiments. The type of instrument is: https://www.google.com/search?client=firefox-b-e&q=anton+paar+dls
Lite sizer 500
Samples:
Various samples (in solution or dispersed) can be measured with this method starting from proteins micells until inorganic nanoparticles.
Accessories:
Varius cuvettes for DLS: single use, glass, closeable quartz
Cuvettes for zeta potential: PS cuvettes
Available equipment:
Differential Scanning Calorimetry (DSC) measures the difference in the amount of heat required to increase the temperature of a sample and reference as a function of temperature and therefore considers its energetic variation.
NLM takes advantage of tightly focused ultra-short laser pulses (fs) to excite non-linear optical phenomena like Second Harmonic Generation, Third Harmonic Generation, Two-Photon and Three-photon excited Fluorescence. Along with laser raster-scanning of the sample, non-linear imaging microscopy of large areas is accomplished within seconds.
Confocal microscopy (CM) is an optical imaging technique that creates a virtual plane or slice, many micrometers deep within the analyzed sample. Compared to conventional microscopy, it provides fine detailed images of higher quality and with more contrast. In addition, virtual 3-D images of the analyzed microstructure can be obtained.
The thermal analyses are the set of techniques in which a physical property of a substance is measured as a function of temperature (or time) while the sample is subjected to a controlled temperature program (heating, cooling, isotherm).
Tools for the characterisation of nanoparticle dispersions and of their interfaces are needed for obtaining colloids, nanofluids, emulsions, which have various applications ranging from microfluidics, to life sciences, energy efficiency, etc.
