Exploration of modified cyclone separator for the enhanced recovery of inhalable spray dried cubosomal powder intended to be used for lung delivery

The study was conducted with the aim to fabricate a cyclone separator capable of providing cubosomal powder with enhanced recovery, uniform size, and high aerosolization efficiency. For that purpose, Classical cyclone design (CCD) and Texas cyclone design (TCD) process parameters (number of effective turns (Ne), inlet air velocity (Vi), pressure drop (ΔP), and cut point diameter (dpc)) were utilized to obtained five geometrical parameters (length of cyclone body (Lb), length of cyclone cone (Lc), height (H) and width (W) of inlet section and air exit diameter (De)) of modified cyclone (type XVII). The design analysis predicted the lowest dpc of 1.5 μm along with an enhanced amount of cubosomal powder collection. The Design of Experiment (DoE) and Signal to Noise (S/N) ratio were employed to evaluate the effect of formulation, process parameter, and cyclone design on device removal efficiency, aerosolization efficiency, fine particle fraction, and yield of cubosomal powder. The modified cyclone provides 1.8 fold enhanced cubosomal powder recovery, which has been associated with increased ΔP inside the cyclone separator. The optimized inhalable spray-dried cubosomal powder possess a sufficient geometrical diameter (dG) (3.9 ± 0.25 μm) and aerodynamic diameter (dA) (2.04 ± 0.15 μm) to deliver formulation to deeper lung tissues. Overall, the findings pointed towards the industrial benefits of developed cyclone design as it experimentally provides enhanced recovery of cubosomal powder in the size range of 1–5 μm with its desirable aerosolization properties.