Powder Technology, Vol.380, 18-25, 2021
Relationship between crystal structures and physicochemical properties of lamotrigine cocrystal
Nowadays, pharmaceutical cocrystals are an alternative approach to the synthesis of new solids without altering active pharmaceutical ingredients of the drug. In this study, lamotrigine (LTG) theophylline (THP) cocrystal monohydrate (1:1:1) and LTG glutarimide (GLU) cocrystal (1:1) were synthesized and characterized by single-crystal X-ray diffraction, powder X-ray diffraction, and Fourier transform infrared analysis. The Hirshfeld surface and 2D fingerprint of the LTG molecule in LTG-THP-H2O and LTG-GLU indicated that the main intermolecular forces between two LTG coaystals molecules are H center dot center dot center dot N/N center dot center dot center dot H and H center dot center dot center dot O. Dissolution results and stability studies demonstrated that the properties of LTG were enhanced by coaystal formation. Contrary to LTG-GLU, LTG-THP-H2O posed slower dissolution rate and higher stability capability, which can be ascribed to the hydrated structure in LTG-THP-H2O and the aminopyridine dimer structure in LTG-GLU. Hence, it is necessary to select the conformers purposefully as to improve the corresponding performance of LTG. (C) 2020 Elsevier B.V. All rights reserved.