Micromeritics Analytical Services offers a variety of techniques to measure particle size of materials. Specifically, we offer the following technique(s):
Laser Light Scattering [ Example Report]
X-Ray Sedimentation [ Example Report]
Electrical Sensing Zone [ Example Report]
Particle Shape Analysis and Dynamic Image Analysis
Nano Particle Size
H.E.L. Subsieve AutoSizer (SAS)
Laser Light Scattering Technique utilizes Mie and Fraunhofer Theories to determine particle size distribution from a light scattering pattern. We have available (5) Micromeritics Saturn Digisizer 5205 and the Malvern Mastersizer 2000 for this technique. The Saturn Digisizer 5200 is the highest resolution instrument available, capable of distinguishing small differences in your sample. If you prefer to use a dry sample dispersion, we would use the Malvern Mastersizer 2000 with the Scirocco dry powder feeder. The particle size range is 0.02 um to 2000 um.
Mastersizer Example Report
The X-Ray Sedimentation Technique takes advantage of the natural tendency of particles to separate by size as they settle through a liquid medium. The mass fraction in each size class is determined by the adsorption of soft X-rays. We utilize the Sedigraph III 5120 which has a particle size measurement range is 0.1 um to 300 um.
Electrical Sensing Zone, commonly known as the Coulter principle, employs an electrical circuit created between two electrodes immersed in an electrolyte on opposite sides of a small orifice. An electrical signal proportional to the volume of the particle is produced as particles are swept through the orifice by a flow of the electrolyte. The technique is used both to count particles and to determine particle concentration in a solution. Currently we use the Elzone 5390 particle size analyzer for this technique. The particle diameter measurement range is 0.5 um to 300 um.
Particle shape effects often have a significant influence on final product performance parameters such as flowability and spray patterns for inks and toners, abrasive efficiency, and bio-availability to name just a few. There are several techniques used to determine particle shape and an almost endless variety of ways to evaluate the data. Micromeritics Analytical Services uses optical microscopy, scanning electron microscopy, and dynamic image analysis to report particle shape parameters. Dynamic Image Analysis is an automated technique which uses a high resolution CCD camera to capture images of particles as they pass through a detection zone. Once this image has been captured we can apply different shape parameters to calculate a particle size distribution. We use a product from Particulate Systems, called the Particle Insight for this measurement. The particle measurement range is 3 to 300 micrometers.
Nanoparticle sizing and Zeta Potential determination using Dynamic Light Scattering (DLS) or Photon Correlation Spectroscopy (PCS) with a Beckman Coulter DelsaNano as well as the Particulate Systems Corduan Vasco. This technique is primarily used to report the particle size of nanoparticles in suspensions, inks, and emulsions. The zeta potential provides information as to the stability of the dispersion or emulsion.
The H.E.L. Limited Subsieve AutoSizer (SAS) is a new addition to the established field of air-permeability particle sizing. It has been developed as a direct and improved successor to the widely used Fisher Model 95 Sub-Sieve Sizer (FSSS). The SAS uses the principle of pressure drop across a packed bed of powder. By varying the sample height, and hence the “porosity” of the bed, average surface area and particle size can be determined as a function of pressure drop in accordance with the Carmen equation. The SAS measures particle size in the range of 0.2 µm to 75 µm and has a compression accuracy of less than 0.05 mm.
Sieves - We offer particle size analysis using three different sieve techniques; a Ro-Tap sieve, sonic sifter, and alpine airjet. The particle diameter measurement range is 45 um to 10 mm.
Particle counting and concentration using Photozone or Light Obscuration with an AccuSizer Model 770. The particle size range is 0.5 to 400 micrometers. This technique is specifically useful in USP methods <788> and <789> for detecting particulates in injectable solutions.
To assist customers with interpretation of their results we offer the following technical documents and articles. If you still have questions, please do not hesitate to contact Micromeritics Analytical Services at 770-662-3630.
Particle Size Brochure
A Primer on Particle Sizing by Static Laser Light Scattering
The Perserverance of the Sedigraph Method of Particle Sizing
Using Dynamic Image Analysis to Measure Fiber Particles.pdf
Interpretation of Particle Size Reported by Different Analytical Techniques
VIDEO - Electrical Sensing Zone particle size and count technique and its pharmaceutical applications
VIDEO - Using Dynamic Image Analysis for Characterizing Irregularly Shaped Particles