SOLID DISPERSION ADSORBATE–A NOVEL TECHNIQUE FOR DISSOLUTION ENHANCEMENT OF FEBUXOSTATAbstract
The objective of the present investigation was to improve dissolution characteristics of febuxostat, a BCS class – II drug, by formulating it as solid dispersion adsorbate. Solid dispersion adsorbate(SDA) was prepared using labrasol, transcutol and lutrol F127 as carriers and neusilin as adsorbent. Formulation was prepared using combination of melt and adsorption technique. Optimized formulation was characterized by fourier transform infrared spectroscopy (FTIR), differential scanning calorimetry (DSC) and X-ray diffraction (XRD). In-vitro dissolution profile was compared with the marketed product. SDA comprising of febuxostat, neuslin and the three carriers in a ratio of 1:2:4 was considered as optimized formulation. FTIR spectroscopy revealed intermolecular hydrogen bonding with neusilin. DSC scan showed absence of melting peak of febuxostat, which indicates solubilization of drug in carriers and conversion of crystalline to amorphous form. This point was further confirmed by XRD. The percentage yield obtained was 90% and there was 10% increase in the dissolution rate of the optimized formulation compared to the marketed product. The dissolution efficiency was found to be 37% of the optimized formulation. Significant increase in the dissolution characteristics of febuxostat was noticed. The enhancement in dissolution rate of febuxostat can be due to hydrogen bonding between the drug and neusilin, micellar solubilisation of drug in carrier, improved wettability and amorphization as confirmed by FTIR, DSC and XRD studies. The results indicated that the SDA is a promising approach for the dissolution enhancement of febuxostat and can be used for the development of suitable solid dosage form for commercialization.