Polymorphism of gemfibrozil: Investigation by thermal and spectroscopic methods

Author(s)

Holanda, Bruno B. C. ^[1] ; Bannach, Gilbert ^[1] ; Silva, M. Ramos ^[2] ; Eusebio, M. Ermelinda S. ^[3] ; Castro, Ricardo A. E. ^{[3, 4]}

Affiliation

^[1] Sao Paulo State Univ, UNESP, Sch Sci, Chem Dept, BR-17033260 Bauru, SP - Brazil

^[2] Univ Coimbra, Dept Phys, CFisUC, P-3004516 Coimbra - Portugal

^[3] Univ Coimbra, Dept Chem, CQC, P-3004535 Coimbra - Portugal

^[4] Univ Coimbra, Fac Pharm, P-3000578 Coimbra - Portugal

• Document type: Journal article
• Source: Thermochimica Acta; v. 675, p. 113-118, MAY 2019.
• Web of Science Citations: 0

Abstract

The knowledge of polymorphism of active pharmaceutical ingredient is relevant in the pharmaceutical field. In this work, a multidisciplinary approach involving differential scanning calorimetry, polarized light thermal microscopy, X-ray powder diffraction and attenuated total reflectance infrared spectroscopy was used to investigate polymorphism of gemfibrozil (GEM), an important fibric acid derivative, in melting cooling/heating cycles. An amorphous phase, Tg = - 34 degrees C, and two monotropic crystalline polymorphs with very close melting temperatures, form I, T-fus,T-I = 59.0 degrees C, and form II, T-fus,T-II = 58.0 degrees C, were identified, being form I the stable phase. In some experiments the forms were obtained concomitantly. The crystallization process seems to be dependent on molten liquid memory. Thereby, this effect could be due to low molecular mobility in the liquid state resulting from the relatively long carbon chain structure of GEM. (AU)

• FAPESP's process: 17/08820-8 - Synthesis and characterization of biopolymers from vegetable oils and glycerol following the principles of green chemistry
• Grantee: Gilbert Bannach
• Support Opportunities: Regular Research Grants