Figure 5.
Schematic experimental set up for impaction study (a) and aerodynamic particle size distributions of 99mTc-LAI (b). Andersen cascade impactor (ACI) was used for this experiment in which the levels of LAI droplets on individual stages were measured gravimetrically (mass) and via quantification of radioactivity (counts per minute (CPM) of 99mTc). The aerosol particle distribution determined gravimetrically overlapped with that determined by the radioactivity measurement. About 65% of the total deposition was found in the middle stages.