Micronization of Levofloxacin Hydrochloride by the Supercritical Antisolvent Precipitation Method from Single-Phase and Two-Phase CO2–Acetone Mixtures

The effect of the pressure and concentration of a micronized substance in a solution on the size and morphology of levofloxacin hydrochloride particles obtained using supercritical antisolvent (SAS) precipitation is investigated. It is shown that the crystallization of levofloxacin from the two-phase CO 2 –acetone–levofloxacin system leads to the production of particles with a bimodal size distribution. An increase in pressure leads to a change in the precipitation regime, and as a result, the crystallization of smaller particles. Vapour–liquid equilibrium curves are obtained for the CO 2 –acetone–levofloxacin hydrochloride system at a temperature of 40°C.