Monodisperse protein nanoparticles production by supercritical assisted atomization

Monodisperse nanoparticles of bovine serum albumin (BSA) and lysozyme (LYS) were generated using supercritical assisted atomization (SAA). The impact of several key factors, including the solvent effect, precipitator and saturator temperatures, concentration of protein solutions, and the flow rate ratio of carbon dioxide to protein solutions, on the morphology and size of protein particles was examined. Increasing the ethanol content in the protein solution reduced the particle size, likely due to enhanced secondary atomization by CO₂-dissolved aqueous ethanol. Higher precipitator and saturator temperatures increased protein particle size. This effect was attributed to intermolecular aggregation from thermal denaturation. Under optimal conditions, the mean sizes of the BSA and LYS particles were 430 nm and 300 nm, respectively, along with an average process recovery of approximately 60 %. In addition, high-temperature processing enhanced the hydrolytic resistance of protein particles and could be used for the controlled release of drug formulations.