Small- and wide-angle X-ray scattering (SWAXS) for quantification of aspirin content in a binary powder mixture.

This article presents a novel application of small and wide angle X-ray scattering (SWAXS) in the assessment of aspirin and lactose content in a binary pharmaceutical powder formulation. It is shown that the content correlates with the intensity of the SAXS signal and the intensity of polymorph fingerprints in the WAXS spectra that are collected from the same samples. Because the polymorph WAXS fingerprints and the SAXS signal are two independent characteristics of the same sample, simultaneous SWAXS analysis provides the basis for a dual independent assessment of the same contents.