Establishing the Vitrocell® Powder Chamber as a particle size-selective platform for in vitro dry powder testing
S.Steiner1, M. Hittinger2, K. Knoth2, H. Gross2, S. Frentzel1, A. Kuczaj1, J. Hoeng1, M. Peitsch1, T. Krebs3
1 PMI R&D, Philip Morris Products S.A., Quai Jeanrenaud 5, CH-2000 Neuchâtel, Switzerland
2 PharmBioTec GmbH, Science Park 1, 66123 Saarbrücken, Germany
3 Vitrocell® Systems GmbH, Fabrik Sonntag 3, 79183 Waldkirch, Germany
Summary
Inhaled aerosol particles deposit on the epithelia of the respiratory tract mainly due to sedimentation, impaction and diffusion that, in their kinetics, strongly depend on particle size and flow patterns. As a result, the deposition efficiency of different sized particles is variant in each regions of the respiratory tract1. This has to be considered when testing dry powders for their biological activity in vitro, as the biological response to particle deposition on in vitro models is a function of the combined action of particle mass, surface and number2.
The Vitrocell® Powder Chamber was developed for the size-selective deposition of dry powders on in vitro test systems in order to simulate the regionally different deposition efficiency of different particle sizes.
We tested the performance of the Vitrocell® Powder Chamber in cell-free exposure experiments using dry powders as test material. Our findings demonstrate that the system allows control of the size distribution of the deposited powder within the targeted ranges. The deposition was uniform across the area of the exposure chambers, but we observed relatively high variations in the powder mass deposition in individual exposure chambers.
Taken together, our results demonstrate that the Vitrocell® Powder Chamber is a valuable tool for in vitro testing of dry powders that could be candidates for inhalable therapeutics or consumer products.
