Design, characterization and in vitro evaluation of DRY powder inhaler formulations containing antibiotic combinations against common nosocomial infection factors

In this study, a dry powder inhaler formulation was developed containing synergistic antibiotic combination. First, synergistic activitiy in combinations of amikacin and cefepime and the best synergistic ratios in combination were tested on Pseudomonas aeruginosa, Klebsiella pneumoniae and Acinetobacter baumanii strains isolated from the patients suffering from pulmonary disease by using the microbiological tests. After determining the active ingredients and their proportions, the formulation was prepared using excipients such as mannitol, trehalose, l-leucine, which are frequently used in dry powder inhaler preparations. Solutions were spray dried with nano spray dryer. The dry powder inhaler formulations were characterized by DSC, FT-IR and TGA analyses. The aerosolization performance measured via the next generation impactor. High Performance Liquid Chromatography (HPLC). Particle size distribution was measured with Mastersizer. Kirby-Bauer disk diffusion test was used to evaluate efficacy performance. As a result, an effective, stable, safe formulation with high aerosolization performance, theoretically reaching the alveoli and having a fine particle fraction at the desired level was prepared.