Evaluation of dynamic image analysis for characterizing pharmaceutical excipient particles.

The capability of the newly developed dynamic image analysis instrument QicPic equipped with the high-speed dry-powder-dispersing device was investigated systematically using various MCC particles. Instrument cross-validation was conducted by comparing the particle size distribution of spherical particles obtained with the QicPic and with a conventional laser diffraction instrument (HELOS). While good agreement was observed with spherical particles, significant differences were found when analyzing rod-shaped Ceolus KG-1000 particles, revealing the intrinsic difference in operating principles between these two techniques. Particle shape distributions of several spherical and rod-shaped samples obtained with the QicPic were compared to scanning electron micrographs (SEMs), and semi-quantitative agreement was obtained. The particle size and particle shape of a series of binary particulate systems composed of both spherical (CP-102) and rod-shaped (KG-1000) particles of varying mass ratios were analyzed using the QicPic. The particle size and shape distributions of these binary mixtures were also computed using the distributions of the pure components weighted by their respective mass fractions. Comparisons between the measured and computed distributions appeared to indicate that the QicPic overestimated the amount of KG-1000 particles present in all the mixtures. Further analysis revealed that the observed discrepancy might be caused by a particle porosity effect.