Dynamic Light Scattering (DLS)
Dynamic Light Scattering (DLS) used to measure particle and molecule size is also known as Photon Correlation Spectroscopy (PCS).
Evaluate particle size distribution of very small particles 0.3nm – 1µm that is invisible for Optical Microscopy and Laser Diffraction. This gives you the possibility to resolve such challenging tasks as:
- Investigation of secondary structure and stability
- Evaluate particle size of micelles and viruses
- Studying particle size of organic and inorganic nano-particles and pigments
Typical applications are emulsions, micelles, polymers, proteins, nano-particles, or colloids.
The effect of temperature on particle size and stability can be investigated. The Dynamic Light Scattering instrument at Particle Analytical is a Nano Zetasizer, where both particle size and zeta-potential can be measured:
- Dynamic Light Scattering. This technique measures the diffusion of particles moving under Brownian motion and converts this to size and a size distribution using the Stokes-Einstein relationship.
- Laser Doppler Micro-electrophoresis is used to measure zeta potential. An electric field is applied to a solution of molecules or a dispersion of particles, which then move with a velocity related to their zeta potential.
For Material Experts:
Instrument and measuring principles, DLS
The Dynamic Light Scattering instrument applied by Particle Analytical (Malvern Nano Zetasizer) measures the particle size distribution using laser dynamic light scattering and analysis of the Brownian motions of particles in the media. Non-Invasive Back-Scatter technology allows measurement on concentrated samples – no or little dilution necessary.
|Instrument||Malvern Nano Zetasizer (DLS) and Zetasizer Ultra Red Label (MADLS)|
|USP/Ph. Eur.||USP 〈788〉 /Ph.Eur. 2.9.50|
|Sample amount||Minimum 12µL for DLS, 1 mL for Zetapotential|
|Temperatures||From 15 to 40°C.|
|Result||The result are given as particle size distribution of stable emulsions and suspensions in the size range 0.3 nm to 1 µm (Zetasizer). Diameter: 0.3 nm – 15 μm|
|Requirements||The viscosity of the emulsion/suspension is required as well as the refractive indices of media and sample.|
Consult our Experts
Dr. Wenbo Wang
Dr. Anna Shevchenko
Arnroth C. A study of protein aggregation processes using Dynamic Light Scattering: Validation of the technique and experimental trial with an active pharmaceutical ingredient.
Babick F (2020) Dynamic light scattering (DLS). In Characterisation of Nano-particles:137-172.
Dieng SM., Omran Z, Anton N, Thioune O, Djiboune AR, Sy PM, Messaddeq N, Ennahar S, Diarra M, Vandamme T (2020) Pickering nano-emulsions stabilised by Eudragit RL100 nano-particles as oral drug delivery system for poorly soluble drugs. Colloids Surf B 191:111010.
Écija-Arenas Á, Román-Pizarro V, Fernández-Romero JM (2021) Separation and characterisation of liposomes using asymmetric flow field-flow fractionation with online multi-angle light scattering detection. J Chrom A 1636:461798.
Li Y, Lubchenko V, Vekilov PG (2011) The use of dynamic light scattering and Brownian Microscopy to characterise protein aggregation. Rev Sci Instr. 82(5):053106.
Sun J, Wang F, Sui Y, She Z, Zhai W, Wang C, Deng Y (2012) Effect of particle size on solubility, dissolution rate, and oral bioavailability: Evaluation using coenzyme Q10 as naked nanocrystals. Int J Nanomedicine 7:5733.
Yu Z, Reid JC, Yang YP (2013) Utilising dynamic light scattering as a process analytical technology for protein folding and aggregation monitoring in vaccine manufacturing. J Pharm Sci 102(12):4284-4290.