title: Aerosol tribocharging and its relation to the deposition of Oxis™ Turbuhaler® in the electrical next generation impactor.
abstract: Although there have been published electrostatic characterisation studies of drug-only Turbuhaler® and lactose carrier-drug formulations, there has not been an investigation into spheronised agglomerates containing micronised lactose and eformoterol, such as in Oxis® Turbuhaler®. Ten doses of Oxis® (12 µ g eformoterol) were dispersed into an electrical next generation impactor (eNGI) in a single run, and runs were conducted in triplicate to determine the aerosol performance and aerosol charge distribution at flow rates of 30, 60 and 90 L/min. Eformoterol fine particle fraction (FPF) reached a maximum of 50%-60% at 60 and 90 L/min, whereas lactose FPF increased from 31% to 42% when flow rate was increased from 30 to 90 L/min. Specific net charge (C/µ g) within the eNGI stages increased from 30 to 60 L/min, but then decreased at 90 L/min. These results were attributed to the shift in balance between surface charging after interparticle and particle-surface collision (dominant at 30 and 60 L/min) and charge separation after impact fragmentation of agglomerates (dominant at 90 L/min). However, the aerosol charge profiles do not suggest that electrostatic forces play a major role in the deposition of Oxis® Turbuhaler® dry powder formulation.
authors.affiliation: Advanced Drug Delivery Group, Faculty of Pharmacy, University of Sydney, Sydney, New South Wales 2006, Australia.
authors.forename: Susan
authors.initials: S
authors.lastname: Hoe
authors.forename: Paul M
authors.initials: PM
authors.lastname: Young
authors.forename: Daniela
authors.initials: D
authors.lastname: Traini
mesh_terms: D000336:Aerosols / Q000008:administration & dosage* / Q000737:chemistry; D001993:Bronchodilator Agents / Q000008:administration & dosage*; D002626:Chemistry, Pharmaceutical; D002851:Chromatography, High Pressure Liquid; D004337:Drug Carriers; D058995:Dry Powder Inhalers; D004560:Electricity; D004983:Ethanolamines / Q000008:administration & dosage*; D000068759:Formoterol Fumarate; D007785:Lactose / Q000008:administration & dosage; D008855:Microscopy, Electron, Scanning; D010316:Particle Size; D055672:Static Electricity
chemical_list: D000336:Aerosols; D001993:Bronchodilator Agents; D004337:Drug Carriers; D004983:Ethanolamines; D007785:Lactose; D000068759:Formoterol Fumarate