Humidity affects the morphology of particles emitted from beclomethasone dipropionate pressurized metered dose inhalers

Publication date: 30 March 2017 Source:International Journal of Pharmaceutics, Volume 520, Issues 1–2 Author(s): James W. Ivey, Pallavi Bhambri, Tanya K. Church, David A. Lewis, Mark T. McDermott, Shereen Elbayomy, Warren H. Finlay, Reinhard Vehring The effects of propellant type, cosolvent content, and air humidity on the morphology and solid phase of the particles produced from solution pressurized metered dose inhalers containing the corticosteroid beclomethasone dipropionate were investigated. The active ingredient was dissolved in the HFA propellants 134a and 227ea with varying levels of the cosolvent ethanol and filled into pressurized metered dose inhalers. Inhalers were actuated into an evaporation chamber under controlled temperature and humidity conditions and sampled using a single nozzle, single stage inertial impactor. Particle morphology was assessed qualitatively using field emission scanning electron microscopy and focused ion beam-helium ion microscopy. Drug solid phase was assessed using Raman microscopy. The relative humidity of the air during inhaler actuation was found to have a strong effect on the particle morphology, with solid spheroidal particles produced in dry air and highly porous particles produced at higher humidity levels. Air humidification was found to have no effect on the solid phase of the drug particles, which was predominantly amorphous for all tested formulations. A critical level of air relative humidity was required to gen...
Source: International Journal of Pharmaceutics - Category: Drugs & Pharmacology Source Type: research