abstract |
A new dry powder inhaler is developed as a pulmonary medicine delivery device for dispersing precise tiny dosages (10 μg-50 mg) of pure carrier-free ultra-fine powdered medicament (<5 μm aerodynamics particle size) into a patient's lung. The powder is drawn from the blister cell and dispersed through an outlet tube assisted by two air streams. The first air stream goes through a the blister cell from its upstream side, to significantly fluidize the medicament in the dose to flow upward. The second one extracts the fluidized powder from downstream of the blister cell for further deagglomeration and dispersion of the medicament powder by shear force. The rotating multi-dose blister can hold up to 60 doses, which are pre-metered with pure ultra-fine powdered medicament. So that it has higher drug loading capability in small volumes, compared to most current dry powder inhalers, which usually use some excipient. The inhaler efficiently disperse the aerosolized medicament in the air stream to the deep interior of patient's lung. The fine particle fraction (<4.7 μm) is reported to reach as high as 80% using this inhaler. |