Time-of-flight aerodynamic particle size analyzers: their use and limitations for the evaluation of medical aerosols.

摘要: ABSTRACT Time-of-flight (TOF) aerosol analyzers are a class of instruments that measure the aerodynamic diameter individual particles following controlled acceleration in well-defined flow field. Two have been used to analyze size medical aerosols: •Aerosizer particle analyzer (TSI Particle Instruments/Amherst, Amherst, MA), •Aerodynamic Sizer (APS) spectrometer (TSI) Both capable sizing several thousand second, making it possible obtain distributions few seconds compared with up 1 hour per measurement using compendial methods based on either multistage liquid impinger or cascade impactor. This rapidity makes TOF analysis attractive for product development, as many different variables can potentially be investigated during short period time. The data thus obtained should caution, however. Several issues, most notably lack direct relationship m...