Co-crystals of active pharmaceutical ingredient-ibuprofen lysine

Abstract

Objective: Co-crystal is defined as a crystalline complex of two or more neutral molecules bound together primarily by hydrogen bonding or other non-covalent interactions. The pharmaceutical co-crystal involves crystal lattice arrangement between an Active Pharmaceutical Ingredient (API) with another pharmaceutically acceptable molecule. Co-crystals of API are preferred since they depict improved solubility, dissolution, stability, compressibility in comparison with API. Ibuprofen lysine (IL), frequently used analgesic and the anti-inflammatory drug has poor aqueous solubility and compressibility. This work shows the feasibility and optimal conditions for the preparation of co-crystals of ibuprofen lysine using Polyvinylpyrrolidone K25 (PK 25) and Polyvinylpyrrolidone K30 (PK 30) as co-formers. Methods: In this study, we prepared and studied the solubility, drug content, flow properties, physical stability of novel co-crystal, consisting of IL and PK 25/PK 30. The co-crystal IL: PK 30 (at a molar ratio of 0.29:0.5) and IL: PK 25 (at a molar ratio of 0.58:1) were characterized by X-ray analysis, infrared spectroscopy and thermal analysis. Furthermore, the tablet formulations of the co-crystals were subjected to in vitro dissolution and in vivo analgesic activity, with the goal of comparing the co-crystals with IL and the marketed tablet of ibuprofen (BrufenR) respectively. Results: The IL: PK co-crystals demonstrated superior solubility and the dissolution properties over IL. The compression properties of the cocrystals were similar to IL. The co-crystals exhibited higher analgesic activity than the marketed tablet. Conclusion: The results indicated the use of PK 25 and PK 30 as safe and promising co-crystal formers.