429PREPARATION AND EVALUATION OF SUSTAINED-RELEASE MATIRX TABLETS OF TIMOLOL MALEATEThe aim of the present study was to prepare and characterize twice-daily sustained-release matrix tablets of Timolol maleate (TM) using different concentrations of natural and semi-synthetic polymers like hydrophilic (Hydroxypropyl methylcellulose-HPMC K100M) alone and its combination with hydrophobic (ethyl cellulose-EC). Formulations prepared by the wet granulation technique and were evaluated for the release of TM over a period of 12 hours using United States Pharmacopoeia (USP) type-II dissolution apparatus. Along with physical properties were also studied. The in-vitro drug release study revealed that formulation F15 (Xanthan gum and EC) could extend the drug release up to 12hours. The most successful formulation of the study, F20 (HPMC and EC, 1:1), extended the drug release up to 12 hours, exhibited satisfactory drug release in the initial hours, and the total release pattern was close to the theoretical release profile. The drug release from optimized formulation (F20) followed first-order kinetics via Non-Fickian (anomalous) diffusion. In conclusion, the results indicated that the prepared sustained-release tablets of TM could perform therapeutically better than conventional tablets with improved efficacy and better patient compliancejanakimpharm@yahoo.co.inResearch532014Timolol maleate,Matrix tablets,Sustained-release,Xanthan gum,Ethyl cellulose, Hydroxy propyl methyl cellulose,In-vitro drug releaseJanakiraman RK, Ramasamy CResearch Scholar, Karpagam University, Coimbatore, Tamilnadu, India,SRM University, Kattankulathur-603203, Tamilnadu, India