Solid-State Screening and Development of Ranolazine Polymorph under different conditions

Purpose The goal of the research was to see if a polymorph of RNZ may improve the medicine's permeability and water solubility. Methods For determination of solvents effect, pure drug (RNZ) was recrystallized from various solvents and crystals obtained were studied for IR. The effect of temperature and humidity was determined by keeping the RNZ crystals at 0 ^o C, 40 ^o C and 70 ^o C for humidity at 75% RH and crystals were studied for IR for any change of RNZ polymorph were created with the solvent evaporation technique. The improved polymorph was physically and chemically characterized by using FT-IR, DSC, XRD and POM. The solubility study of crystalline forms in water and the impact of crystallization on temperature and humidity on crystalline phases was carried out. Results The DSC thermograms of a pure drug (RNZ) and polymorph are studied for a pure drug (RNZ), lone endothermic peak was It has been seen and is situated at 122 ^o C. This spectrum neither showed the presence of water of crystallization nor any indication of glass transition. DSC thermogram of polymorph which was recrystallized from ethanol, exhibited a single endothermic peak at 137 ^o C. According to the XRD study, the diffraction lines of a pure drug (RNZ) were matching with the polymorph. The solvents used for the purification of RNZ exhibited differences in the crystal lattice as supported by FT-IR. Conclusion The solvents used for the purification of RNZ exhibited differences in the crystal lattice. It was interesting to investigate the factors affecting RNZ polymorphic transformation. The transformation was noted at RH = 75% (± 5) for form II while both the formed showed stability at different temperatures.