RESUMO
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.
RESUMO
Objective: The purpose of the present investigation was to formulate hydrodynamically balanced oral In situ gel of glipizide inorder to increase the gastric residence time and to modulate the release behavior of the drug. Material and method: In situgel formulations were prepared by using different concentrations of sodium alginate, calcium carbonate, trisodium citrate and release retardant polymers. pH triggered ionic gelation is the mechanism involved in the present study. Taguchi L9 OA experimental design was employed for the optimization of formulations. All the formulations were subjected to various evaluation parameters. Results: Formulation F9 containing 3% of sodium alginate, 1.0 % of CaCO3, 0.2% of trisodium citrate and 0.5% of HPMC-K100M was selected as optimized batch based on Q12 58.26%, floating time 47.76 sec and drug content 98.2%. The release pattern of drug was found to follow first order. The value of ‘n’ from Korsemeyer equation was found to be 1.00 indicating the drug release by supercase II. The DSC study revealed that there was no incompatibility. Gastroretentive X-ray imaging study on Albino rabbit demonstrated that it was able to float in the stomach for more than 8hrs. Pharmacodynamic study on Wistar rats demonstrated significant hypoglycaemic activity of the optimized formulation. Conclusion: It was concluded that the hydrodynamically balanced oral In situ gel of glipizide could be an effective dosage form which remains buoyant and sustain the drug release for 24hrs.