“…Test conducted at flow rate of 60 L/min for 4 s. For each test formulation, amount particle was determined and analyzed for drug content by UV spectrophotometer (UV-170, Shimadzu, Japan) at 285.5 nm. Starting at the filter, a cumulative mass deposition (undersize in percentage) vs. cut-off diameter of respective stages was derived, the mean mass aerodynamic diameter (MMAD), geometric standard diameter (GSD), fine particle dose (FPD), % fine particle fraction (%FPF) and % mass balance was calculated (Kundawala, Vishnu, & Patel, 2011;Naikwade & Bajaj, 2009). FPF considered as directly proportional to the amount of drug able to reach the pulmonary tract in vivo: consequently, higher the percentage of FPF, deeper the estimated lung deposition will be.…”