Key words: levofloxacin, SCF-micronization, supercritical antisolvent preci pitation (SAS), FTIR and Raman spectroscopy, CD spectroscopy, solubility
Micronization of levofloxacin (LF) — antibacterial drug of fluoroquinolons group —
using Supercritical Antisolvent Preci pitation method (SAS) is studied. Depending on
the type of solvent used in the SAS process, particles of different size (1-10 microns)
and morphology (from thin plates to elongated parallelepipeds) can be obtained.
Characterization of micronized LF forms by FTIR, Raman and circular dichroism
spectroscopies showed that micronization doesn’t cause any changes in chemical
structure of LF or its racemization. Micronization has a significant effect on the rate
of LF dissolution in model media, which depends on the type of the solvent used in
the SAS process. At pH = 4, the LF samples micronized using chlorohydrocarbons
exhibit the highest dissolution rate. At pH = 7.5 the dissolution rate of micronized LF
samples is 15-30 % higher compared to the original one, that can be associated with
the degree of crystallinity / amorphousness, as well as with the morphology of
microparticles formed during the SAS micronization.
doi:10.1134/S1990793116080054