A Holistic View to Particle Sizing

The complexities of particle sizing are often understated and overlooked, with many methods reducing particle sizing results to a single figure without context. These complexities arise from the different physical attributes’ particles develop during processing. Particles created via crystallization can have complex morphologies, structures, and distributions. With different crystallization processes producing different particles for the same compound, it is now critical to replace the “one-size fits all” approach to sizing with newer methods that combine orthogonal analysis techniques.

At APC, we have developed an approach which involves coupling Laser Light Scattering (LLS) and microscopy in a systematic approach tailoring sizing methods to particles crystallised. Adopting this holistic approach to sizing moves from a black box method to a method where key parameters are selected and used for method development. This reduces detrimental errors which often go unnoticed or unchallenged (ghost particles, multiplicative scattering, low dispersion, etc.) while giving a verifiable method for further investigation of unexpected LLS measurements. This not only enables more agile and reliable analytical techniques for particle sizing, but also helps better scrutinise changes to particle size and morphology resulting from changes to process parameters.