Particle Size Analysis
In all product development, the particle size of products and materials is a critical parameter in their manufacture. Changing the particle size distribution of a material has a massive impact on its characteristics and behaviour either during manufacture, within the final product or on its effects within the environment.
The Meritics Lab offer a range of measurement techniques and particle size analysis testing methods that cover virtually all materials — wet or dry, ranging from >1 nm to 5 mm in size. Our expert scientists can help select the most appropriate test for your material/system from the following:
- Laser Diffraction
- Dynamic Light Scattering
- Electrical Sensing Zone
- Dynamic Imaging
- Sieve
Depending on the technique used, we can report:
- Particle size distribution – weighted to volume, number or surface area
- Polydispersity
Additionally, Meritics offer a fully validated method development service.
Get in touch for a quote or to find out more about how we can support you ….
Laser Diffraction
Laser diffraction is based on Fraunhofer theory, where light scattering intensity is proportional to particle size. Smaller particles scatter light at wider angles, and the reverse is true for larger particles. Samples pass through a flow cell, and particle size is calculated from the scatter pattern.
For particles above ~1µm, the diffraction pattern is clear and measurable. Below this range—especially under 0.4µm—the signal becomes vague, limiting accuracy. Some instruments extrapolate data below this threshold, but accuracy suffers.
To overcome this, Beckman Coulter developed PIDS (Polarisation Intensity Differential Scattering). By measuring scatter from both vertically and horizontally polarised light across multiple wavelengths, the system accurately characterises particles below 0.4µm. The LS 13320 XR now achieves real measurements down to 10nm.
Our scientists routinely measure dry powders (e.g. sugar, soil), emulsions, and aqueous/non-aqueous dispersions. Results can be reported by number, volume, or surface area weighting.
Contact us for a quote or to discuss your particle sizing needs.
Electrical Sensing Zone
Beckman Coulter Multisizer 4e, with a range of 0.2µm to 1600µm is widely used in many areas: Life Sciences such stem cells, cell biology, and Industrial such as toner, ceramics, sediments etc. as well as Pharmaceutical applications.
The Coulter Principle (also known as ESZ – Electrical Sensing Zone) is hailed as probably the most significant advance in the field of particle technology, and tens of thousands of Coulter Counter instruments are in regular use worldwide.
Most recently our scientists have been running a lot of water samples on the Multisizer 4e to measure contaminants.
Contact us for a quote or to discuss your particle sizing needs.
Dynamic Imaging
Today microscopic examination and counting and sizing of small particles is commonplace, Meritics work with Yokogawa Fluid Imaging Technologies (YFIT) and their FlowCam Image Analyser range can size from 300nm to 5mm in range, this takes the tedium involved away and frees up the scientist to analyse data comprehensively.
Electron microscopes probe the size range below the limit of optical microscopy and a scanning technique enables pictures of the surface features of even very delicate surfaces to be made in exquisite detail.
Most recently our scientists have been sizing sugar samples on the FlowCam 8000 to measure the size and to give an image of the particles.
Contact us for a quote or to discuss your particle sizing needs.
Sieves
For the characterisation of bulk goods of different forms and sizes, the knowledge of their particle size distributions is essential. The particle size distribution, i.e. the number of particles of different sizes, is responsible for important physical and chemical properties such as solubility, flowability and surface reaction.
In many industries such as food, pharmaceuticals and chemistry traditional sieve analysis is the standard for production and quality control of powders and granules. Advantages of the sieve analysis include easy handling, low investment costs, precise and reproducible results in a comparably short time and the possibility to separate the particle size fractions. Therefore, this method is an accepted alternative to analysis methods using laser light or image processing.
Contact us for a quote or to discuss your particle sizing needs.