Particle size, measurement light microscope

The preservation of particle character and size throughout polymerization itself is very hard to determine. The size of the final polymer particles is easily determined by light scattering or microscopic methods since the dispersions can be diluted without changing the particle size. Measurements of the emulsion droplets in concentrated media on the other hand are a very difficult task and have already been discussed above. 

Suspensions contain micronized drug for proper delivery to and absorption in the respiratory system. Typical particle size of the micronized drug is from 2 to 5 microns [5], Aerodynamic mean particle size as measured by cascade impactor or direct method of microscopic analysis is usually from 0.5 to 4 microns [5], Additional particle-sizing techniques such as light scattering can be used [6],... 

Third, in selecting a particle sizing technique, one must consider the size of the material itself. Most techniques have effective upper and lower limits of detection. Laser diffraction, for example, can measure particles from approximately 0.01 pm to several millimeters. With optical microscopy and image analysis, it becomes very difficult to resolve features that are smaller than a 0.3 pm because of the wavelength of light used in conventional optical microscopes.1... 

The use of ultraviolet light in the microscopic measurement of particle size. J. Franklin Inst., 209 777-789. 

The Zeiss AxioHOME (Highly Optimized Microscope Environment) was developed by pathologists to count, measure and analyze cell structure in biological thin sections. The AxioHOME is a light microscope coupled to a personal computer that allows the microscopist to make measurements on particles whilst still observing the real image. It is highly suited to particle size analysis because the measurements can be exported directly to a spreadsheet [103]. 

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