In-vitro and particle image velocimetry studies of dry powder inhalers

Larissa Gomes Dos Reis; Vishal Chaugule; David F Fletcher; Paul M Young; Daniela Traini; Julio Soria

doi:10.1016/j.ijpharm.2020.119966

In-vitro and particle image velocimetry studies of dry powder inhalers

Int J Pharm. 2021 Jan 5:592:119966. doi: 10.1016/j.ijpharm.2020.119966. Epub 2020 Nov 5.

Authors

Larissa Gomes Dos Reis¹, Vishal Chaugule², David F Fletcher³, Paul M Young¹, Daniela Traini⁴, Julio Soria⁵

Affiliations

¹ Respiratory Technology, Woolcock Institute of Medical Research and Discipline of Pharmacology, Faculty of Medicine and Health, The University of Sydney, Sydney, Australia.
² Laboratory for Turbulence Research in Aerospace and Combustion (LTRAC), Department of Mechanical and Aerospace Engineering, Monash University, Clayton Campus, Melbourne, Australia.
³ School of Chemical and Biomolecular Engineering, The University of Sydney, Sydney, Australia.
⁴ Respiratory Technology, Woolcock Institute of Medical Research and Discipline of Pharmacology, Faculty of Medicine and Health, The University of Sydney, Sydney, Australia. Electronic address: daniela.traini@sydney.edu.au.
⁵ Laboratory for Turbulence Research in Aerospace and Combustion (LTRAC), Department of Mechanical and Aerospace Engineering, Monash University, Clayton Campus, Melbourne, Australia. Electronic address: julio.soria@monash.edu.

PMID: 33161040
DOI: 10.1016/j.ijpharm.2020.119966

Abstract

Inhalation drug delivery has seen a swift rise in the use of dry powder inhalers (DPIs) to treat chronic respiratory conditions. However, universal adoption of DPIs has been restrained due to their low efficiencies and significant drug losses in the mouth-throat region. Aerosol efficiency of DPIs is closely related to the fluid-dynamics characteristics of the inhalation flow generated from the devices, which in turn are influenced by the device design. In-vitro and particle image velocimetry (PIV) have been used in this study to assess the aerosol performance of a model carrier formulation delivered by DPI devices and to investigate their flow characteristics. Four DPI device models, with modification to their tangential inlets and addition of a grid, have been explored. Similar aerosol performances were observed for all four device models, with FPF larger than 50%, indicating desirable lung deposition. A high swirling and recirculating jet-flow emerging from the mouthpiece of the DPI models without the grid was observed, which contributed to particle deposition in the throat. DPI models where the grid was present showed a straightened outflow without undesired lateral spreading, that reduced particle deposition in the throat and mass retention in the device. These findings demonstrate that PIV measurements strengthen in-vitro evaluation and can be jointly used to develop high-performance DPIs.

Keywords: Aerosol performance; Axial; Device; Flow straightener; Fluid dynamics; Grid; Radial velocities; Tangential inlets.

MeSH terms

Administration, Inhalation
Aerosols
Dry Powder Inhalers*
Equipment Design
Particle Size
Powders
Rheology

Substances

Aerosols
Powders