Particle light microscopy

With a resolution of 0.01 qm this technique outperforms optical light microscopy (0.1 pm) and is used, e.g., to examine fine particles such as metal fume. When linked to other facilities such as dispersive X-ray analysis, quantitative data can be obtained. 

Immunohistochemical labeling for electron microscopy is based on the same principles as immunohistochemistry for light microscopy. The differences are that specimen sections must be much thinner (50 100 nm) and the label must be electron-dense. The first electron-dense labels used for immunolabeling at the electron microscope level were ferritin and peroxidase. Peroxidase label can be visualized using DAB reaction product which becomes electron-dense after osmi-cation. With the advent of colloidal gold particles as markers in immunocytochemical... 

Light microscopy can be used to detect particles with regular shapes (e.g., crystals) and microbes like yeast and bacterial cells (Glenister, 1971). Microscopy can also detect some irregular particles such as diatomaceous earth or adsorbents (Glenister, 1974). It is much less informative with amorphous particle hazes. The use of specific stains can, however, provide useful information. An excellent book by Glenister (unfortunately no... 

McCrone, W. C., and J. G. Delly, 1973b. The Particle Atlas, 2nd ed., Vol. II The Light Microscopy Atlas, Ann Arbor Science Publishers, Ann Arbor, Mich. 

Because of this importance, different techniques have been developed to characterize the droplet size distribution in emulsions, each with its own pros and cons. Light microscopy, for example, is qualitative and only suited for particles larger than about 1 )im. When using electron microscopy, correct sample preparation is crucial to the examination and interpretation of the dispersions. The Coulter method is an indirect method which detects a... 

Microspheres intended for nasal administration need to be well characterized in terms of particle size distribution, since intranasal deposition of powder delivery systems is mostly determined by their aerodynamic properties and particle sizes. Commonly used methods for particle size determinations described in the literature are sieving methods [108], light microscopy [58], photon correlation spectroscopy [66], and laser diffractometry [25,41,53,93], The morphology of the microparticles (shape and surface) has been evaluated by optical, scanning, and transmission electron microscopy [66, 95],... 

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