Effect of USP induction ports and modified glass sampling apparatus on aerosolization performance of lactose carrier-based fluticasone propionate dry powder inhaler

Abstract

In the present study, a lactose based dry powder inhaler (DPI) was formulated to probe the effect of three different US Pharmacopeia (USP) induction port (IP) on aerosolization performance DPIs. Additionally, the delivered dose uniformity (DDU) and drug-carrier detachment were studied using the USP modified glass sampling apparatus and force-displacement concept, respectively. Initially, median sized lactose carrier (InhaLac® 160) and a model drug fluticasone propionate (FP) were studied for numerous physicochemical properties. The homogenous drug-carrier blend was prepared using a low shear 3D shaker mixer. The InhaLac® 160 showed typical tomahawk-shaped particles with mean particle size (d50) and average surface roughness of 109.46 μm and 2.70 μm, respectively. Additionally, the laser Raman spectrometry demonstrated the uniform surface distribution of FP across the carrier surface. In the drug-carrier detachment study, FP DPI required >600 g-force to detach the 50% of the FP particles from lactose surface. During cascade analysis, all three USP IPs showed a remarkable variation in drug retention within the IP and pre-separator. The USP modified IP showed superior % fine particle fraction as compared to the USP IP. The difference in aerodynamic dispersion can be attributed to the variation in the design of the USP IPs. Moreover, developed FP DPI showed satisfactory DDU (>88%) when studied using the modified glass sampling apparatus. Briefly, the present study offers a detailed report on aerosolization performance of median sized lactose carrier-based DPIs using different USP IPs.