Crystal growth by solvent evaporation and characterization of metronidazole

Single crystals of metronidazole were crystallized by the slow solvent evaporation method and used as seeds to grow bulk crystals of size 8.0×6.5×2.0 mm3 using top-seeded submerged solution growth. The crystals were characterized using single crystal X-ray diffraction. Fourier transform infrared spectral analysis was made for the absorption bands of various functional groups present in the crystal. UV–vis absorption spectrum was used to identify the presence of nitroimidazole in metronidazole. Morphology study revealed that the growth is prominent along the c-axis and the prominent face is {010}. Thermal stability and thermal decomposition were analyzed using thermo calorimetry.

► Bulk crystals of metronidazole were grown in aqueous solutions by the solvent evaporation and top seeded solution growth methods.
► Crystal habits in different solvents were studied.
► Stability and decomposition were analyzed using thermo-calorimetry.
► FTIR spectral analysis was made.
► Characteristic absorption bands of nitroimidazole were identified using optical spectra.