Analysis of curcumin precipitation and coating on lactose by the integrated supercritical antisolvent-fluidized bed process

Dry powder formulations with potential application in pulmonary drug delivery were produced by integrating the Supercritical Antisolvent (SAS) process with a fluidized bed (FB) under pressure. The simultaneous precipitation and coating of curcumin on lactose was performed in a single step combining the advantages of both processes. Ethanol and acetone were used as solvents. The effects of operating parameters: pressure, temperature, drug-lactose mass ratio, solution flow rate and solution concentration on the drug size, morphology and yield were investigated. Due to the high degree of mixing in the fluidized bed, a uniform coating of curcumin onto lactose was achieved with loading efficiency varying from 71.0 to 93.3% and curcumin particle size between 0.41 and 12.08 μm. Solvent-free curcumin particles with reduced crystallinity were produced while the physicochemical properties of the raw materials were not changed.