To be effective, most drugs need to reach the bloodstream. This is achieved orally, through injections, via the bowels, or with infusions, and with the new “pharmaceutical dosage forms.”
In the transdermal systems a specific dose of medication is absorbed through the skin, or, if in the form of micronized powders, the specific dosage is inhaled either by the mucous membrane of the nasal cavity (nasally) or by the lung (pulmonary delivery), and then distributed via the bloodstream.
The different bioavailability for the various pharmaceutical forms is clearly influenced by the particle size of the carrier substance or the active ingredient itself, which makes this a vital component in a sensible dosage recommendation.
Powders, as an independent dosage type, perform only a minor role, although they are still important as a base material for other dosage forms. Other than their significance in drug effectiveness, particle size distribution plays a critical part in the development of suitable manufacturing methods and in the quality control element of the production process.
The example below shows the particle size distribution of ampicillin, a semi-synthetic antibiotic from the group of beta-lactam antibiotics (penicillin), measured with a small volume dispersion unit in hexane. Hexane was chosen because the sample material dissolves in water and other solvents. An externally prepared suspension was pre-dispersed in an ultrasonic bath for 30 seconds before the actual measurement.
This information has been sourced, reviewed and adapted from materials provided by FRITSCH GMBH - Milling and Sizing.
For more information on this source, please visit FRITSCH GMBH - Milling and Sizing.