ABSTRACT
The aim of the present work is fabrication of dual cross linked sodium alginate(SA)/montmorillonite(MMT)microbeads as a potential drug vehicle for extended release of curcumin(CUR).The microbeads were prepared using in situ ion-exchange followed by simple ionotropic gelation technique.The developed beads were characterized by Fourier transform infrared spectroscopy(FTIR),differential scanning calorimetry(DSC),thermogravimetric analysis(TGA),X-ray diffraction(X-RD)and scanning electron microscopy(SEM).The effect of MMT on encapsulation efficiency of CUR and intercalation ki-netics was investigated.Dynamic swelling study and in vitro release study were investigated in simu-lated intestinal fluid(pH 7.4)and simulated gastric fluid(pH 1.2)at 37℃.Results suggested that both the swelling and in vitro release studies were influenced by the pH of test media,which might be suitable for intestinal drug delivery.The release mechanism was analyzed by fitting the release data into Korsmeyer-Peppas equation.
ABSTRACT
The objective of this research was to formulate and evaluate hydrodynamically balanced controlled drug delivery system of Losartan. This dosage form is associated with many advantages especially increased bioavailability and reduction in dosing frequency. The formulation was designed adopting optimization technique, which helps in setting up experiments in such a manner that the information is obtained as efficiently and precisely as possible. Initially, considering buoyancy as the main criteria, blank tablets were compressed for different formulae with various polymers like HPMC, MC and EC. The formula selected for design had a combination of Losartan, HPMC, EC and MC. The tablets were prepared by direct compression method and evaluated for Losartan content in vitro release profile and buoyancy. The dissolution study was carried out in simulated gastric fluid using USP dissolution test apparatus employing paddle stirrer. Duration of buoyancy was observed simultaneously when the dissolution has carried out The variation in weight was within the range of ±4% complying with pharmacopoeial specifications (±Z5%). The drug content of Losartan floating tablet 8.455±0.0085 mg in of optimized formulations indicating content uniformity. The buoyancy of the tablets was range 15.345±0.1321 hrs the maximum buoyancy was seen in P6, which has a high level of drug to polymer ratio. The in-vitro release was found to be in the range between the 79.12% to 90.45%.. The formulation P6 has an in vitro release of 79.12% showed the release of the drug in the controlled manner. The optimized formulation P6 exhibited responses that were comparable with that of the predicted values of the design in optimization technique. This indicates the suitability of the technique chosen for the present dosage form.