The effect of ethanol on the habit and in vitro aerodynamic results of dry powder inhalation formulations containing ciprofloxacin hydrochloride

Edit Benke; Christina Winter; Piroska Szabó-Révész; Eva Roblegg; Rita Ambrus

doi:10.1016/j.ajps.2021.04.003

The effect of ethanol on the habit and in vitro aerodynamic results of dry powder inhalation formulations containing ciprofloxacin hydrochloride

Asian J Pharm Sci. 2021 Jul;16(4):471-482. doi: 10.1016/j.ajps.2021.04.003. Epub 2021 May 28.

Authors

Edit Benke¹, Christina Winter^{2

3}, Piroska Szabó-Révész¹, Eva Roblegg^{2

3}, Rita Ambrus¹

Affiliations

¹ Institute of Pharmaceutical Technology and Regulatory Affairs, University of Szeged, Szeged H-6720, Hungary.
² Institute of Pharmaceutical Sciences, Pharmaceutical Technology and Biopharmacy, University of Graz, Universitätsplatz 1, Graz A-8010, Austria.
³ Research Center Pharmaceutical Engineering GmbH, Inffeldgasse 13, Graz A-8010, Austria.

Abstract

In the case of dry powder inhalation systems (DPIs), the development of carrier-free formulations has gained increased attention. Thereby, spray-drying is a promising technology and is widely used to produce carrier-free DPIs. Numerous works have been published about the co-spray-drying of active ingredients with various solid excipients and their effect on the physicochemical characteristics and aerodynamic properties of the formulations. However, only a few studies have been reported about the role of the solvents used in the stock solutions of spray-dried formulations. In the present work, DPI microcomposites containing ciprofloxacin hydrochloride were prepared by spray-drying in the presence of different ethanol concentrations. The work expresses the roughness, depth and width of the dimples for particle size as a novel calculation possibility, and as a correlation between the MMAD/D_0.5 ratio and correlating it with cohesion work, these new terms and correlations have not been published - to the best of our knowledge - which has resulted in gap-filling findings. As a result, different proportions of solvent mixtures could be interpreted and placed in a new perspective, in which the influence of different concentrations of ethanol on the habit of the DPI formulations, and thus on in vitro aerodynamic results. Based on these, it became clear why we obtained the best in vitro aerodynamic results for DPI formulation containing 30% ethanol in the stock solution.

Keywords: Aerodynamic properties; Dry powder inhaler; Ethanol; Particle engineering; Roughness.