Supercritical CO₂-assisted spray-dried drug particle production

In this work, we have investigated supercritical CO₂(scCO₂)-assisted spray drying for the production of drug particles using ketoprofen as a model Active Pharmaceutical Ingredient (API). We have used an experimental and Computational Fluid Dynamics (CFD) simulations approach to explore the hydrodynamics and particle formation pathways of a scCO₂-assisted spray drying. The Eulerian-Lagrangian CFD framework was developed to describe the scCO₂-assisted atomization of a drug solution through a micro-orifice two-fluid nozzle structure. The commercial CFD code, Ansys FLUENT (2024R2) was used. The relevant thermodynamic sub-models were integrated via user-defined functions. Experimental validation and calibration were guided by real-time laser-diffraction-based particle sizing methods as well as offline dynamic light scattering measurements. The comparison of simulated and experimentally measured average particle sizing data showed good agreement across three different feed solution concentrations at an injection pressure of 110 bar and feed solution flow rate of 1 mL/min. The developed model offers a cost-effective tool for design, simulation and optimization of relevant drug particle production setups.