Carrier-free Formulation of Dry Powder Inhalates
Nanoparticle coating of drug microparticles
Viktoriya Mykhaylova1, Karin Dresely1, Fabian Klar1, Nora Anne Urbanetz2
Corresponding author: Prof. Dr. Nora Anne Urbanetz, Research Center Pharmaceutical Engineering GmbH, Inffeldgasse 21 A, 8010 Graz, Austria; e-mail: email@example.com
The present study aims at evaluating the suitability of nanoparticle covered drug microparticles as an alternative to conventional carrier based formulations for pulmonary drug delivery. Colloidal silicon dioxide was used as model nanoparticle, lactose as model drug. The influence of the nanoparticle to microparticle ratio and the preparation procedure were evaluated. In comparison to nanoparticle free formulations nanoparticle covered lactose particles showed enhanced flowability, single dose uniformity and respirable fraction. However, there is an optimum amount of nanoparticles and further increasing it leads to a deterioration of these characteristics. Furthermore, with respect to the mode of preparation, mixtures prepared by electrostatically supported mixing, meaning that the dispersion of the nano- and microparticulate fraction is assisted by triboelectric charging of these fractions prior to the mixing procedure, are superior to those prepared by conventional mixing using a tumble mixer in terms of flowability, single dose uniformity and respirable fraction.