2013 年 30 巻 p. 125-143
Both the FDA (U.S. Food and Drug Administration) and ICH (International Conference on Harmonisation) have urged the incorporation of Quality by Design (QbD)1) into the manufacture of pharmaceutical products2).The performance of many pharmaceutical manufacturing processes and the performance of some pharmaceutical products requires a knowledge of powder properties. Under the principles of QbD it is possible to adjust processes to account for variations in powder properties. These adjustments, in turn, require knowledge of the relation between powder properties and manufacturing performance. This relation between powder properties and performance is often not well understood; thus, the required information is not collected.In this paper, particle-particle and particle-surface interactions are considered to be a source of product variability. As particle size effects are intertwined with particle adhesion effects this topic is also considered. From the discussion below, it can be seen that the surface chemistry of particles can vary due to mechanical treatment, crystallization solvent, and surface contamination. Variations in surface chemistry affect interparticle adhesion and thus may lead to process or product performance changes. Issues concerning the role of interparticle adhesion that are related to tableting and dry powder inhalers are discussed in some detail.It is clear that a deeper understanding of the powder state and the establishment of appropriate analytical tools will be required to fully implement QbD. Improvements in particle sizing technologies, improvements powder sampling procedures and measurements of particle surface properties will be required. It is hoped that this paper will stimulate thought on this issue.
