Adhesion force between drug particles and carriers surface for dpi efficiency
Kay, Khine Maw
Date of Issue2017-06-16
School of Chemical and Biomedical Engineering
The failure to detach the drug particles from the carrier’s surfaces when reaching the target site is one of the main issues in Dry Powder Inhalation (DPI) formulation. This is generally due to the interactions of adhesion force between powder particles and carrier surfaces. In this study, the adhesion force relationship between drug particle and carrier surface and the factors affecting between them in DPI were examined by Atomic Force Microscopy (AFM). Five different types with different sizes ranging from 5 to 40um of pollen-shape hydroxyapatite (HA) particles were used as model carrier. The methodology uses a functionalised AFM tip which is achieved by attaching a common drug particle, budesonide to the apex of the cantilever tip and measuring the force experienced between the cantilever tip and the surface of HA particles. To determine the factors affecting the adhesion force, the topography of HA carriers were examined and it was found that micro-peaks with nano-space or nano-peaks with nano-space topography allow the efficient attachment and detachment of budesonide to the carrier surface, thereby enhancing the delivery of the drug particles to the lungs. The study also showed that HA particles is more suitable for drug particles with smooth surface as it provide better binding and has great potential to be used as drug carriers in DPI. The carrier’s size, shape and its surface roughness should be synthesized carefully to provide suitable binding sites for efficient detachment and release of drug particles at designation.