title: Preparation and characterization of physically modified glass beads used as model carriers in dry powder inhalers.
abstract: The aim of this work is the physical modification and characterization of the surface topography of glass beads used as model carriers in dry powder inhalers (DPIs). By surface modification the contact area between drug and carrier and thereby interparticle forces may be modified. Thus the performance of DPIs that relies on interparticle interactions may be improved. Glass beads were chosen as model carriers because various prospects of physical surface modification may be applied without affecting other factors also impacting interparticle interactions like particle size and shape. To generate rough surfaces glass beads were processed mechanically by friction and impaction in a ball mill with different grinding materials that were smaller and harder with respect to the glass beads. By varying the grinding time (4 h, 8 h) and by using different grinding media (tungsten carbide, quartz) surfaces with different shades of roughness were generated. Depending on the hardness of the grinding material and the grinding time the surface roughness was more or less pronounced. Surface roughness parameters and specific surface area were determined via several complementary techniques in order to get an enhanced understanding of the impact of the modifying procedure on the surface properties of the glass beads.
authors.affiliation: Research Center Pharmaceutical Engineering GmbH, Inffeldgasse 13, Graz, Austria. sarah.zellnitz@rcpe.at
authors.forename: Sarah
authors.initials: S
authors.lastname: Zellnitz
authors.forename: Jakob Dominik
authors.initials: JD
authors.lastname: Redlinger-Pohn
authors.forename: Michael
authors.initials: M
authors.lastname: Kappl
authors.forename: Hartmuth
authors.initials: H
authors.lastname: Schroettner
authors.forename: Nora Anne
authors.initials: NA
authors.lastname: Urbanetz
mesh_terms: D004337:Drug Carriers / Q000737:chemistry*; D004339:Drug Compounding; D058995:Dry Powder Inhalers; D005898:Glass / Q000737:chemistry*; D010316:Particle Size; D013499:Surface Properties
chemical_list: D004337:Drug Carriers