title: Characterization of a New High-Dose Dry Powder Inhaler (DPI) Based on a Fluidized Bed Design.
abstract: The objective of this study was to develop a new high-efficiency dry powder inhaler (DPI) that can effectively aerosolize large masses (25-100 mg) of spray dried powder formulations. The DPI was designed to implement a concept similar to a fluidized bed for aerosolization using small mixing balls made of polytetrafluoroethylene along with a larger, hollow dosing sphere filled with the powder. The performance of the fluidized bed DPI was compared, based on emitted dose (ED) and aerosolization efficiency, to other recently developed capsule-based DPIs that were designed to accommodate smaller powder masses (~2-20 mg). The inhalers were tested with spray dried excipient enhanced growth (EEG) formulations that contained an antibiotic (ciprofloxacin) and hygroscopic excipient (mannitol). The new fluidized bed design produced an ED of 71% along with a mass median aerodynamic diameter of 1.53 μm and fine particle fractions <5 and 1 μm of 93 and 36%, respectively, when used to deliver a 100 mg loaded mass of EEG powder with the advantage of not requiring multiple capsules. Surprisingly, performance of the device was further improved by removing the mixing balls from the inhaler and only retaining the dose containment sphere.
authors.affiliation: Department of Mechanical and Nuclear Engineering, Virginia Commonwealth University, 401 West Main Street, P.O. Box 843015, Richmond, VA, 23284-3015, USA.
authors.forename: Dale R
authors.initials: DR
authors.lastname: Farkas
authors.affiliation: Department of Pharmaceutics, Virginia Commonwealth University, Richmond, VA, USA.
authors.forename: Michael
authors.initials: M
authors.lastname: Hindle
authors.affiliation: Department of Mechanical and Nuclear Engineering, Virginia Commonwealth University, 401 West Main Street, P.O. Box 843015, Richmond, VA, 23284-3015, USA. pwlongest@vcu.edu.|Department of Pharmaceutics, Virginia Commonwealth University, Richmond, VA, USA. pwlongest@vcu.edu.
authors.forename: P Worth
authors.initials: PW
authors.lastname: Longest
mesh_terms: D000336:Aerosols; D000900:Anti-Bacterial Agents; D002939:Ciprofloxacin; D058995:Dry Powder Inhalers; D004867:Equipment Design; D005079:Excipients; D008353:Mannitol; D010316:Particle Size; D011208:Powders; D011312:Pressure
chemical_list: D000336:Aerosols; D000900:Anti-Bacterial Agents; D005079:Excipients; D011208:Powders; D008353:Mannitol; D002939:Ciprofloxacin
keywords: Excipient enhanced growth formulation; Fluidized bed DPI; High efficiency dry powder inhaler; High-dose DPI; Inhaled antibiotics; Inhaled clearance enhancers; Inhaled surfactants