Screening of Carbamazepine-Ibuprofen Co-Crystal Formation Using Non-Stoichiometric and Stoichiometric Methods

The paper presents the co-crystal screening study of carbamazepine (CBZ) and ibuprofen (IBU) as a co-crystal former (CCF) using non-stoichiometric (solid addition of CBZ to saturated solution of co-crystal former (CCF) and stoichiometric (1:1 mol of CBZ and CCF) methods. In the non-stoichiometric method, CBZ-IBU co-crystal was prepared in various solvents and left to equilibrate in three conditions; stagnant, manually agitated and shaking in 72 hours whereas in the stoichiometric method, evaporation, solvent drop grinding and dry grinding were used. The crystals produced from the screening process were characterized using differential scanning calorimetry (DSC) and optical microscopy. The co-crystal of CBZ-IBU was found to have successfully formed via the non-stoichiometric method in formic acid. DSC analysis revealed that the remaining crystals produced were either CBZ or IBU as indicated by their respective melting point.