The development of a novel high-dose pressurized aerosol dry-powder device (PADD) for the delivery of pumactant for inhalation therapy.
The performance of a novel dry powder inhaler designed to deliver exceptionally high doses was investigated using pumactant as a model powder. Pumactant (a synthetic lung surfactant consisting of a phospholipid mixture), with a 90th percentile particle size of 2.92 microm is highly cohesive, has a high moisture affinity (6.2% w/w at 45% RH), and is predominantly amorphous. The device (pressurized aerosol dry-powder delivery [PADD]) utilizes pressurized gas to aerosolize a powder bed from a reservoir and delivers it through a conventional mouthpiece. The influence of loaded dose on dry powder delivery and can pressure on aerosolization efficiency was investigated. Analysis of the delivered dose studies suggested a linear relationship between loaded dose and delivered dose (R(2) = 0.96, for loaded doses of 0-250 mg), with a delivery efficiency of 70%. Analysis of the aerosolization efficiency using a Marple Miller type impactor suggested fine particle fractions (particles with an aerodynamic diameter of <5 microm) of approximately 30% using canister pressures of 8-14 bars. These results indicate that the PADD device may be a useful tool in delivering high-dose medicaments, as a carrier-free formulation, to the deep lung.
Pharmaceutical Technology Research Group, Department of Pharmacy, University of Bath, Bath, United Kingdom.
Paul M
PM
Young
Jim
J
Thompson
Derek
D
Woodcock
Mo
M
Aydin
Robert
R
Price
D000280:Administration, Inhalation; D000335:Aerosol Propellants; D004305:Dose-Response Relationship, Drug; D004867:Equipment Design; D004869:Equipment Safety; D006801:Humans; D009330:Nebulizers and Vaporizers; D010316:Particle Size; D010743:Phospholipids / Q000008:administration & dosage*; D011312:Pressure; D012138:Respiratory Therapy / Q000295:instrumentation*; D012680:Sensitivity and Specificity
D000335:Aerosol Propellants; D010743:Phospholipids; C068829:artificial lung expanding compound