Micromeritics Analytical Services (MAS) – Reports Average Particle Size of Nanoparticles - 1/16/2007
Measuring the primary particle size of nanoparticles, not in a stable colloidal suspension, has caused problems for researchers for some time. The only widely accepted option was to perform TEM analysis to determine the primary particle size, but that was expensive and time-consuming. Recently, studies have demonstrated that an average primary particle size for nanoparticles can be calculated using the following equation for either spherical- or cubic-shaped nanoparticles. The equation will vary slightly for other uniformly shaped materials. Average Particle Size* = ( 6 / BET surface area** X Density*** ) X 1000 *Average Particle Size = (nanometers) **surface area = (sq. m/g) ***Density = (g/cc) Micromeritics Analytical Services will measure the BET surface area using a gas adsorption technique and the true density using a gas pycnometer, and then calculate the average particle size. The part number for this new application is 005-70. This technique will provide a good estimation of the average primary particle size of dry nanoparticles assuming the particles are of uniform shape and size.