Characterization of Carbamazepine from Recrystallization of Various Organic Solvents Using Slow Evaporation Method

Abstract

Abstract Background: Carbamazepine is a class II Biopharmaceutical Classification System (BCS), which means that carbamazepine has high membrane permeability and low solubility. Recrystallization is a way to modify crystals in an effort to change the physicochemical properties and dissolution rates of drugs. Objective: This study aims to evaluate the physicochemical properties of carbamazepine through the recrystallization of various solvents. Methods: This research carried out the recrystallization process of carbamazepine by evaporation of multiple solvents, namely ethanol, tetrahydrofuran (THF), and chloroform. The recrystallized solids were characterized using FTIR spectrophotometry, powder X-ray diffraction, and differential scanning calorimetry (DSC). Furthermore, the micromeritic evaluation and dissolution test was carried out. Results: The analysis results with FTIR and PXRD showed no change in the chemical structure of carbamazepine, but it caused changes in the internal structure and changes in the shape or called polymorphism of the carbamazepine crystals. Micromeritic evaluation showed a difference in the functional properties of the crystallized solids compared to pure carbamazepine, where the crystalline solids from ethanol recrystallization showed better micromeritic properties than the pure form. Carbamazepine crystals recrystallized using THF solvent have the highest dissolution rate than others, where at 60 minutes, the amount of dissolution is 65.09%. Conclusion: The recrystallization of carbamazepine with ethanol, tetrahydrofuran, and chloroform results in new polymorphs. The physicochemical properties of recrystallized solids differ from those of pure carbamazepine. Carbamazepine powder recrystallized with tetrahydrofuran solvent has the highest dissolution rate compared to other solvents. Keywords: carbamazepine, crystallization, solvent, solids characterization, slow evaporation