• Publication Date: 12/01/2023
  • Author(s):
    Mitchell, Jolyon P. Roberts, Daryl L.
  • Organization(s):
    Applied Particle Principles, LLC Jolyon Mitchell Inhaler Consulting Services, Inc.
  • Article Type: Technical Articles
  • Subjects: Instruments, Particle Characterization, Product Development/Formulation, Testing, Validation, and Regulatory Compliance

In the first article, we explored the robustness of the pharmacopeial methodology for the determination of delivered dose uniformity (DDU) for orally inhaled products to bias in volumetric flow rate setting from variations in ambient pressure. In this article, we extend the analysis to evaluate how the determination of the second performance-related critical quality attribute, aerodynamic particle size distribution (APSD) might be affected by similar ambient pressure changes, as well as other factors.

The findings from this further exploratory analysis of the underlying physical processes involved with the determination of APSD of the aerosol emitted from a passive DPI following methodology advocated in the pharmacopeial compendia again add support for the robustness of these methods. However, we have identified several facts for the reader to consider as part of his or her development programs for the performance testing of these orally inhaled products.

Read Part 1–Exploring the robustness of the pharmacopeial methods for testing dry powder inhalers (DPIs); Part 1: Delivered dose uniformity (DDU)

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