A novel device for aerosol plume evaluation of orally inhaled and nasal drug products

Accurate measurement of aerosol velocity is important for evaluating the performance of orally inhaled and nasal drug products (OINDPs). This study aims to demonstrate and evaluate the accuracy and reliability of a novel instrument, the “OptoSleeve,” which integrates a compact optical diagnostic system designed to measure aerosol velocity and plume duration across various aerosol drug emitting devices. The OptoSleeve employs the laser extinction concept to capture aerosol flow behaviour. Experiments in this study were performed using nasal sprays, pressurised metered dose inhalers (pMDIs), and dry powder inhalers (DPIs) under a range of flow rate conditions, and the results were compared with reference measurements obtained from Particle Imaging Velocimetry (PIV) and Particle Tracking Velocimetry (PTV). The OptoSleeve was shown to provide velocity data that closely align with those obtained using PIV and PTV. Further complementary studies, conducted using computational fluid dynamics modelling, revealed that integrating the OptoSleeve with a regulatory-approved throat replica (e.g., the United States Pharmacopeia throat) has minimal impact on aerosol transport and deposition dynamics within the replica.