Evaluation of in vitro Dissolution Profile and Physicochemical Characterization of Polymer Based Formulations of Sparingly Soluble Rosuvastatin
Keywords:
Rosuvastatin, low solubility, physical mixing, solid dispersion, solvent evaporation.Abstract
Rosuvastatin (RVT) is a BCS class II antilipidemic crystalline drug, which exhibits low bioavailability
due to its very poor aqueous solubility; therefore, it is challenging to develop a proper formulation of RVT. To
enhance solubility and bioavailability of this API, an attempt has been made by implementing solid dispersion
technique. Solid dispersion (SD) technique is a solubility enhancing technique where one or more active entities are
dispersed in an inert medium (matrix or carrier) at solid state. In this study, different ratios of Kollicoat® IR (KIR)
and Kollidon® 90F (KF90) polymers were used with API to prepare various formulations by physical mixing (PM)
and SD approaches; here solvent evaporation technique was used whereas methanol was used as solvent which was
completely evaporated from the homogenously dispersed system by placing in a water-bath at 60 - 65°C and then in
oven for 30 minutes at 50°C. Among the formulations, RVT-KF90 SD formulations showed the most promising
result in in-vitro study in terms of drug release profile (78.04 – 99.21%) in comparison to pure RVT (63.1%) and
physical mixing of RVT with those polymers. USP dissolution apparatus type II was used at 37°C ± 0.5°C with 50
rpm to conduct the in-vitro experiment. The experiment also unraveled that the dissolution of RVT improved with
increasing the amounts of polymers. Subsequently, stability of the developed formulations was conducted by Fourier
transforms infrared spectroscopy (FTIR) and differential scanning calorimetry (DSC) as well as scanning electron
microscopy (SEM). The results obtained from FTIR ensured no involvement of any significant drug-excipient
interaction. Moreover, the DSC study signified thermal stability at high temperature. Besides, the SEM micrograph
illustrated homogenous distribution of RVT in the polymer and transformation of crystal-like RVT into amorphous
formulations.
