The characterization of dry powders for inhalation is based on compendial methods that provide a precise and robust representation of the human throat and upper airway for testing purposes in the context of product quality control. However, the current USP pharmacopeia method considers a non-physiological representation of the human mouth-throat, the USP Throat, and a constant flow during testing.The flow achieves a 4 kPa pressure drop and an inhalation volume of 4L, which does not account for the variability inherent in the patient population.

The main goals of this work were:

1. to compare the recently developed Alberta Idealized Throat (AIT) and Breathing Pattern Simulator BRS) with current to compare the recently developed Alberta Idealized Throat (AIT) and Breathing Pattern Simulator BRS) with current to compare the recently developed Alberta Idealized Throat (AIT) and Breathing Pattern Simulator BRS) with current pharmacopeia standard in the aerodynamic performance assessment of a model DPI formulation while applying a square wave profile;
2. to compare these new developed technologies with additional collection surface coating, mimicking the particle impaction that occurs in vivo.