Automated SEM-EDS has been evaluated as a potential tool for determining the API particle size distribution (PSD) and morphological characteristics, such as aspect ratio and roundness of particles, of a DPI. The only requirement for this technique is an elemental distinction, such as the presence of an inorganic element in the API, in comparison to the excipients. In this instance, the automated SEM-EDS technology has been applied to characterize a bromine- containing API in comparison to the carbon-rich lactose excipient of a DPI product.
