title: The potential use of Raman mapping to investigate in vitro deposition of combination pressurized metered-dose inhalers.
abstract: Scanning near-infrared Raman microscopy has been used to map aerosol particulate deposits produced from pressurized metered-dose inhalers (pMDI). A commercially available combination asthma therapy pMDI (Ventide, Allen and Hanbury, UK), containing salbutamol and beclometasone dipropionate, was analyzed by conventional in vitro quantitative analysis and scanning Raman microscopy. Raman maps, taken from Andersen cascade impactor plate stages 3 and 5 (over 100 x 100 microm areas) suggested good correlation with chemical analysis of the respective stages. Scanning Raman microscopy allows visual differentiation between formulation components (not possible using conventional imaging techniques), while potentially allowing chemical quantification.
authors.affiliation: Pharmaceutical Technology Research Group, Department of Pharmacy and Pharmacology, University of Bath, Bath, BA2 7AY, UK.
authors.forename: D Fraser
authors.initials: DF
authors.lastname: Steele
authors.forename: Paul M
authors.initials: PM
authors.lastname: Young
authors.forename: Robert
authors.initials: R
authors.lastname: Price
authors.forename: Timothy
authors.initials: T
authors.lastname: Smith
authors.forename: Stephen
authors.initials: S
authors.lastname: Edge
authors.forename: David
authors.initials: D
authors.lastname: Lewis
mesh_terms: D000336:Aerosols / Q000032:analysis; D000420:Albuterol / Q000008:administration & dosage / Q000032:analysis; D018927:Anti-Asthmatic Agents / Q000008:administration & dosage / Q000032:analysis; D001507:Beclomethasone / Q000008:administration & dosage / Q000032:analysis; D036501:Metered Dose Inhalers; D008855:Microscopy, Electron, Scanning; D011312:Pressure; D013059:Spectrum Analysis, Raman / Q000379:methods*
chemical_list: D000336:Aerosols; D018927:Anti-Asthmatic Agents; D001507:Beclomethasone; D000420:Albuterol