Moxifloxacin Micronization via Supercritical Antisolvent Precipitation

Supercritical antisolvent (SAS) precipitation is employed for micronization of moxifloxacin (MF), an antibiotic from the fluoroquinolone group, to develop new dosage forms of MF. With this technique, we produced, in a controllable fashion, MF particles with different sizes (0.6–8.0 μm) and morphologies (from polygonal sheets to elongated rectangular prisms). The infrared and circular dichroism spectroscopy data suggest that micronization of MF via SAS does not alter its chemical structure or cause racemization. We demonstrate that micronized forms of MF drug substance exhibit a 20 to 30% increase in the dissolution rate, as compared to the initial MF form, in a physiological medium (pH 7.4). The dissolution rate of the microparticles obtained via SAS micronization depends on their size, morphology, and degree of crystallinity. The various data obtained in this study will be used in formulating new dosage forms of MF for treatment of drug-resistant forms of tuberculoses.