Co-crystals of carvedilol: Preparation, characterization and evaluation

Abstract

Objective: Carvedilol an antihypertensive drug, exhibits poor solubility and dissolution rate. Hence an attempt has been made to prepare the Co-crystals of Carvedilol to increase the solubility and dissolution rate. Methods: The Co-crystals of Carvedilol were prepared using coformer such as succinic acid, fumaric acid and oxalic acid by Solvent evaporation method. The prepared Co-crystals were evaluated for solubility, dissolution rate and micrometric properties. The Co-crystals were characterized by scanning electronic Microscopy (SEM), FT-Infrared Spectroscopy (FTIR), Differential Scanning Calorimetry (DSC) and X-ray Diffractometry (XRD). Results: SEM of pure carvedilol and Cocrystals morphology clearly showed the formation of a new solid phase with the coformer. The FT-IR spectra indicate the shifting of characteristic peak in the Co-crystals but does not show any interaction between the co-former used. DSC data showed the change in the endotherm with the melting point of Co-crystals. XRD spectra indicate the notified difference in the 2θ and the intensity of the peaks. Solubility of CAR-SA Cocrystals (2.225±0.35), CAR-FA Cocrystals (1.880±0.20) and CAR-OA Cocrystals (1.128±0.23) was markedly improved compared to pure Carvedilol (0.376±0.06). Thus the increased in dissolution rate for CAR-SA Cocrystals (93.72 %). was highest whereas CAR-FA Cocrystals (91.56 %), CAR-OA Cocrystals (88.93 %) compared to pure Carvedilol (40.3) within 60 Min. The Carvedilol cocrystals were also showed improvement in the flow properties compare to pure Carvedilol. Conclusion: Hence the Co-crystal formation could be helpful to improve the solubility, dissolution and micromeritic properties of Carvedilol.