@PhdThesis{diss_mods_00021707,
  author = 	{Renner, Niklas Ludwig},
  title = 	{Understanding interparticle interactions in dry powder inhalation: glass beads as an innovative model carrier system},
  year = 	{2017},
  publisher = 	{Christian-Albrechts-Universit{\"a}t zu Kiel},
  address = 	{Kiel},
  keywords = 	{Inhalation; glass; beads; interparticle; interactions},
  abstract = 	{Delivery of drugs via the pulmonary route is the most common approach to treat diseases of the respiratory system, e.g. asthma bronchiale. Here, the active pharmaceutical ingredient is generally formulated in a so-called interactive mixture with a coarse and inert carrier. This enhances flowability and therefore dose metering and dispersibility. Interparticle interactions between carrier and drug govern aerosolisation behaviour of the blend and consequently the efficacy of the drug deposition in the lungs. These interactions, for their part, are influenced by a variety of factors including chemical and topographical properties of the carrier surface. To investigate their effect, glass beads were utilized as a model carrier system. Different modification techniques were applied for surface alteration including silanisation, treatment with hydrofluoric acid and ball milling with tungsten carbide. Chemical properties proved to have different effects for drugs with varying hydrophilicity on pulmonary deposition. For the surface topography, same trends could be observed for the aerodynamic performance of blends with budesonide or formoterol fumarate. Indentations on micro-scale significantly reduced the fine particle fraction, while roughening of the surface led to a remarkable increase. The latter could be ascribed to decreased adhesive forces. In the course of this thesis, the impact of the dimensioning of important inhaler parts of a dry powder inhaler was investigated as well. Results showed that air-ducting parts like the air inlet or the mouthpiece should be narrowed to increase the air stream velocity and consequently kinetic energy and level of turbulence. In addition, a small grid proved to be beneficial, as it led to a slow and controlled discharge of the deagglomeration chamber.},
  url = 	{https://macau.uni-kiel.de/receive/diss_mods_00021707},
  file = 	{:https://macau.uni-kiel.de/servlets/MCRFileNodeServlet/dissertation_derivate_00007297/Diss_Renner.pdf:PDF},
  language = 	{en}
}