Existence of pharmaceutical substances as polymorphs, pseudo-polymorph or solvates is ofimmense interest in research and drug development. Physicochemical properties of polymorphseffect melting, conductivity, crystal shape, color, dissolution rate, stability and solid state reactions.Polymorphism is defined as the ability of the same substance to exist as two or more crystallinephases that have different arrangements of the molecules in the crystal lattice. This study reports onthe polymorphic forms of Nifedipine.Nifedipine treats cardiovascular disorders. It is a calcium channel blocker agent. It forms yellowcrystals, melting at 172-177 °C. It exists in three polymorphic forms: Polymorphic form I (m.p. 169-173 °C ) is thermodynamically stable, Polymorphic form II (m.p. 161-163 °C) and Polymorphicform III (m.p. 150 °C) and is the metastable modification.The objectives of this research include preparation of the two crystal forms of Nifedipine: FormII (1,4-dioxane solvate ) and form III (amorphous-crystalline form). Form I (nifedipine “pure”) is thecommercially available product. Characterization of the polymorphic forms was accomplished byDSC, DEA, PXRD, SEM, and Raman Spectroscopy as well as Macro-photography. In this study theelectrical conductivity of the polymorphic forms of Nifedipine is reported. It is also desired todevelop a unique thermal analytical method for evaluating polymorphic solids by ElectricalConductivity Analysis [ECA] from 10-3 to 10+8 PS/cm.
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