(692c) Surface Modification of Pollen Shape Carriers for Improved Dry Powder Inhalation Efficiency

Pollen-shape particles were found to have great potential as drug carriers for dry powder inhalation. However, the relatively strong interparticle force on the carrier surface limits the detachment of drug particles after the drug-carrier mixture is released from inhalers. In this study, surface etching technique was employed to modify the carrier particle surface. Four surface etching temperature were examined. A low surface etching temperature were not able to modify the particle surface while a high surface etching temperature destroyed the pollen-shape morphology. Two of the surface etching conditions were then utilized and the physical properties of the resulting particles were characterized. Budesonide was used as the model drug and Rotahaler® is used as the model inhaler. The drug delivery efficiency using the two type of carrier particles are also characterized by Andersen Cascade Impactor (ACI) using inhalation rates of 30 liter/min and 60 liter/min. While there is a reduction in the emitted dose (ED), the fine particle fraction (FPF) of the drug was increased when pollen-shape carriers that were processed by surface etching were used.