Question

The particle size of a particular substance is 98.2 nm in radius. It is likely to be a


True solution

Colloid

Suspension

Pure substance

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Answer 1

Answer:

Physicochemical and Biopharmaceutical properties of drug substances and dosage forms can be highly affected by the particle size, a critical process parameter in pharmaceutical production. The fundamental issue with particle size analysis is the variety of equivalent particle diameters by generated by different methods, which is largely ascrible to the particle shape and particle dispersion mechanism involved. Thus, to enable selection of the most appropriate or optimial sizing technique, cross- correlation between different techniques may be required. This review offers an in- depth discussion on particle size analysis pertaining to specific pharmaceutical applications and regulatory aspects, fundamental principles and terminology, instrumentation types, data presentation and interpretation, in line and process analytical technology. For illustration purposes special consideration is given to the analysis of aerosals using time - of - flight and cascade impactor measurements, which is supported by a computational analysis conducted for this review.