Preparation of budesonide nanosuspensions for pulmonary delivery: Characterization, in vitro release and in vivo lung distribution studies

The main objective of the present article was to prepare stable and well-dispersible budesonide (BUD) nanosuspensions by microfluidizer method. The morphology, particle size, and zeta potential of formulation were investigated and in vitro release and in vivo lung distribution were evaluated. Characterizations showed that BUD nanosuspensions were spherical in shape with a smooth surface. The measured average particle size was 122.5 +/- 6.3 nm, and potential was - 13.6 +/- 0.4 mV. In vitro release behavior of three batches BUD nanosuspensions had a good reproduction. The deposition distribution of BUD different formulations was measured using a modified multi-stage liquid collision method. The data showed that BUD nanosuspensions have the most outstanding deposition distribution with fine particle ratio 82.2%. Compared with normal particle and micronized particles, nanosuspensions were easier to be distributed in lung. After inhalation of 1 h, the drug concentration can reach 872.9 ng/g, which was extremely significantly different from normal particles (p < 0.01) and significantly different from micronized particles (p < 0.05).