Antisolvent micronization of BSA using supercritical mixtures carbon dioxide plus organic solvent

In this work, expanded liquid antisolvent (ELAS) process has been used to micronize bovine serum albumin (BSA) solubilized in water. Carbon dioxide mixtures with ethanol, acetone or isopropyl alcohol, at expanded liquid conditions, have been used as the antisolvent. The effect of process parameters, such as the kind of co-antisolvent and the organic co-antisolvent/water/carbon dioxide mole fraction on the morphology and dimensions of the precipitates, was studied. Changing co-antisolvent and operating conditions, we obtained nanoparticles (with a mean diameter of about 60 nm +/- 10 nm), sub-microparticles (with a mean diameter of 470 nm +/- 130 nm), microparticles (with a mean diameter of 0.93 mu m +/- 0.37 mu m) and expanded microparticles with an empty core (with a mean diameter of about 9 mu m +/- 5 mu m). Fourier transform infrared analysis on BSA powders revealed that, using acetone as co-antisolvent, no modifications of the protein secondary structure were induced by ELAS processing. (C) 2014 Elsevier B.V. All rights reserved.