In vitro cell integrated impactor deposition methodology for the study of aerodynamically relevant size fractions from commercial pressurised metered dose inhalers

Purpose: The purpose of this study was to present a modified Andersen cascade impactor (ACI) as a platform to evaluate the deposition and subsequent transport of aerosol micropaticles across airway epithelial cells.
Methods: The impaction plate of an ACI was modified to accommodate up to eight Snapwells. Aerodynamic particle size distribution of the modified ACI was investigated with two commercially available formulations of Ventolin® (salbutamol sulphate) and QVAR® (beclomethasone dipropionate). Deposition and transport of these drug micropaticles across sub-bronchial epithelial Calu-3 cells were also studied.
Results: The modified ACI demonstrated reproducible deposition patterns of the commercially available pressurised metered dose inhalers compared to the standard ACI. Furthermore, the Calu-3 cells could be placed in different stages of the modified ACI. No significant effect was observed among the transport rate of different particle sizes deposited on Calu-3 cells within the range of 3.3 to 0.4 μm.
The use of the cell compatible ACI to assess the fate of microparticles after deposition on the respiratory epithelia may allow for better understanding of deposited microparticles in vivo