SOLID STATE CHARACTERIZATION OF LINEZOLID CRYSTAL FORMS

The pharmaceutical industry utilizes a wide variety of techniques to research, develop and manufacture active pharmaceutical ingredients (APIs). Linezolid is a synthetic antibacterial agent of the oxazolidinone class used for the treatment of serious infections caused by Gram-positive bacteria that are resistant to several other antibiotics. Two crystal modifications (polymorphs) of Linezolid have been obtained through recrystallization using organic solvents under different conditions. The two forms were fully characterized with x-ray powder diffraction, differential scanning calorimetry, fourier transform infrared spectroscopy and hot stage polarizing optical microscopy. The study revealed one metastable form, undergoing heat mediated transformation to another form. Such an observation is of great importance since it can affect the stability and pharmaceutical performance of an active pharmaceutical ingredient and final dosage form.