The Formulation, Preparation, and Evaluation of Celecoxib Nanosuspensions: Nanosizing via High-Pressure Homogenization and Conversion of the Nanosuspensions into Dry Powders by Spray Drying and Freeze Drying

Celecoxib (CEL), a nonsteroidal anti-inflammation drug (NSAID), is categorized as a Class II drug (low solubility, high permeability) in the Biopharmaceutics Classification System (BCS). The aim of this study is to develop a novel formulation of CEL nanosuspensions in the form of dried powder for tableting or capsuling. In this study, CEL was formulated into nanosuspensions to improve its solubility. CEL nanosuspensions were prepared using the precipitation method followed by high-pressure homogenization. Drying of the nanosuspensions was performed by spray drying and freeze drying. We examined the impact of various formulation and processing parameters on the nanoparticles. The CEL nanoparticles were characterized by particle size analysis, differential scanning calorimetry (DSC), powder X-Ray diffraction (PXRD), attenuated total reflectance Fourier transform infrared spectroscopy (ATR-FTIR), and dissolution tests. The choice of solvent, stabilizer, and surfactant appeared to have significant impacts on the crystallization and particle size and, consequently, the solubility of the CEL nanoparticles. CEL chemical stability was maintained throughout both drying processes. Both spray-dried and freeze-dried CEL nanosuspensions showed rapid dissolution profiles compared to raw CEL due to the nanosized particle dispersion with the presence of a lag phase. The freeze-dried nanosuspension showed a slight delay in the first 20 min compared to the spray-dried nanosuspension, after which dissolution progressed with a lag phase that represents aggregation.