Comparison of the TSI model 3306 impactor inlet with the Andersen cascade impactor: Solution metered dose inhalers

Paul B. Myrdal, Stephen W. Stein, Erik Mogalian, William Hoye, Abhishek Gupta

Research output: Contribution to journalArticle

12 Scopus citations


The product performance of a series of solution Metered Dose Inhalers (MDIs) were evaluated using the TSI Model 3306 Impactor Inlet and the Andersen Cascade Impactor (ACI). The goal of the study was to test whether the fine particle and coarse particle depositions obtained using the Model 3306 were comparable to those results obtained by ACI testing. The analysis using the Model 3306 was performed as supplied by the manufacturer as well as with 20 cm and 40 cm vertical extensions that were inserted between the Model 3306 and the USP Inlet. Nine different solution formulations were evaluated. The drug concentrations ranged from 0.08 to 0.8% w/w and the ethanol cosolvent concentration varied between 5 and 20% w/w. In general, it was found that good correlations between the two instruments were obtained. However, for formulations containing 10-20% w/w ethanol it is shown that an extension fitted to the Model 3306 yielded an improved correlation to those obtained from the ACI.

Original languageEnglish (US)
Pages (from-to)859-868
Number of pages10
JournalDrug Development and Industrial Pharmacy
Issue number8
StatePublished - Oct 25 2004



  • Andersen cascade impactor
  • Impactor inlet
  • MDI
  • Metered dose inhaler

ASJC Scopus subject areas

  • Pharmacology
  • Pharmaceutical Science
  • Drug Discovery
  • Organic Chemistry

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