Electrostatics in pharmaceutical solids

Pharmaceutical solids are likely to accumulate electrostatic charge through handling processes encountered both in industry and during clinical use. Important advances in the past decade have continued to improve our understanding and enabled better control of electrostatics. Although certain areas have been studied more extensively than others, much remains unexplored at the fundamental level and in vivo deposition studies are required to confirm the impact of charged aerosols in humans. This review has summarised the key fundamentals, highlighted the relevance in industrial and clinical settings, evaluated the factors that influence charging and discussed measurement techniques with regards to pharmaceutical powders. The understanding gained could potentially have regulatory implications, and could assist in the development and manufacture of pharmaceutical powders and their delivery systems.