INTRODUCTION Drug delivery in conventional dosage forms often suffers from the drawbacks of repeated drug administration and large fluctuations in drug blood levels. The frequency with which a rapidly absorbed and distributed drug must be given in a conventional dosage form is dependent upon intrinsic properties of the drug, viz. elimination half-life (t 1/2 ) 1 . Sustained release dosage forms are designed to complement the pharmaceutical activity of the medicament in order to ABSTRACT The

more »

... ctives of the present investigation are to prepare and evaluate drug loaded sustained release matrix tablets for "diabetes", using hydrophilic and hydrophobic polymers, by applying 2 3 factorial designs. The sustained release tablets of Glimepiride were prepared employing different concentrations of Ethyl cellulose, HPMC K15M and Eudragit L100 in different combinations as a rate retarding polymer by wet granulation technique using 2 3 factorial designs. The quantity of polymers, Ethyl cellulose, HPMC K15M and Eudragit L100 required to achieve the desired drug release was selected as independent variables, X1, X2 and X3 respectively whereas, time required for 80% of drug dissolution (t 80 %) was selected as dependent variables. Totally eight formulations were designed and are evaluated for hardness, friability, diameter, thickness, % drug content, In-vitro drug release and In-vivo studies. From the Results it was concluded that all the formulation were found to be within the Pharmacopoeia limits and the In-vitro dissolution profiles of all formulations were fitted in to different Kinetic models, the statistical parameters like intercept (a), slope (b) & regression coefficient (r) were calculated. Polynomial equations were developed for t 80% . The formulation (F9) containing three polymers in optimized level using 2 3 factorial designs showed high t 80% value of 24 hours. The selected formulation (F9) follows Higuchi's kinetics, and the mechanism of drug release was found to be Anomalous type (Non-Fickian, n=0.5809). KEYWORDS Glimepiride, 2 3 factorial designs, Ethyl cellulose, HPMC K15M and Eudragit L100.