Solid Forms of Ciprofloxacin Salicylate: Polymorphism, Formation Pathways, and Thermodynamic Stability (original) (raw)

The crystallization of ciprofloxacinan antibacterial fluoroquinolone compoundwith salicylic acid resulted in the isolation of five distinct solid forms of the drug, namely, an anhydrous salt, two polymorphic forms of the salt monohydrate, methanol and acetonitrile solvates, and the salt-cocrystal hydrate. The salicylate salts were investigated by different analytical techniques ranging from powder and single crystal X-ray diffractometry, differential scanning calorimetry, thermogravimetric analysis, variable temperature powder X-ray diffraction, dynamic vapor sorption analysis, dissolution, and solubility investigations. Real-time in situ Raman spectroscopy was used to investigate the mechanochemical formation pathways of the different solid polymorphs of ciprofloxacin salicylate. The mechanism of the phase transformation between the crystalline forms was evaluated under mechanochemical conditions. It was found that the formation pathway and kinetics of the grinding process depend on the form of the starting material and reaction conditions. The analysis of the solid-state thermal evolution of the hydrated salts revealed the two-step mechanism of dehydration process, which proceeds through a formation of the distinct intermediate crystalline products.

Sign up for access to the world's latest research.

checkGet notified about relevant papers

checkSave papers to use in your research

checkJoin the discussion with peers

checkTrack your impact