Dynamic Light Scattering (DLS) analysis allows us to confidently measure the size distribution profiles of particles in the sub-micron range.  This technique is particularly useful to study the behavior of nanoparticles in suspensions.

Combined with zeta potential information, DLS data, versus time, provides insights into (for example) the tendency for nanoparticles to agglomerate.  As well as solid particles, DLS is invaluable for “seeing” how surfactant molecules arrange together as micellar structures.  Such arrangements alter with surfactant concentration and the concentration of simple electrolyte ions present.  This information supports research and development in drug delivery and consumer products such as shampoos and toothpastes, to give just two examples.

Potential Applications

Nanoparticles are a focus area for many industries, potential applications include:

• Nanoparticle use in targeted oncology treatments
• Increasing the available power in batteries
• Controlled formation of larger materials with specific properties
• Slurry control – wanted or unwanted flocculation / sedimentation

How It Works

The sample is suspended in a solution to give slight turbidity.  A laser is fired through the sample and the light is scattered by suspended particles.  By monitoring the intensity of the scattered light versus time at a fixed angle, this data can be mathematically converted to a nanoparticle size and distribution within the sample.  Only a small sample size is required (typically 1ml suspension in a cuvette) and the equipment can deal with a range of active concentrations with measurement time only requiring a few minutes.  This makes it an ideal analytical technique for high value or early stage development testing and final quality control.

DLS is mainly suited to particulate of less than 1 micron which remains in suspension without the need of agitation, for example:

• Proteins
• Surfactant micelles
• Vesicles
• Nanoparticles
• Biological cells
• Primary agglomerations in gels