Mixing of Particulate Material Studied by near Infrared Spectroscopy

Abstract

This study aimed to characterise by near infrared (NIR) spectroscopy the physical parameters that are relevant to the quality of a pharmaceutical blend, such as mean particle size of a granular material, incompatibilities between particle size of the blend components and segregation tendencies. Binary blends consisting of granulated material (96% m/m) and an active pharmaceutical ingredient (API) (4% m/m) were prepared. Granule particle size was studied using the Kubelka–Munk function. In addition, NIR spectroscopy was applied for the monitoring of the API concentration during a blending step. Convection and diffusion phases were clearly identified.