The aim of research was to develop self nanoemulsifying drug delivery technology containing low aqueous soluble drug allopurinol for improving solubility, dissolution and bioavaibility. Preliminary screening were carried on the basis of maximum solubility of allopurinol in oil, surfactant, co-surfactant and pseudo-ternary phase diagram was constructed to identify the ratio of surfactant and co-surfactant for nanoemulsion formulation using water titration method. Based on the solubility study, Labrafil M 1944 CS, Cremophor RH 40, Transcutol used as oil, surfactant, and co-surfactant respectively. Pseudo-ternary phase diagram was constructed to identify the ratio of surfactant and co-surfactant for nanoemulsion formation by water titration method. As per the ternary phase diagram ratio of Smix in 2:1 was identified with maximum emulsification area. SNEDDS composed of 35 % Labrafil M 1944 CS, 43.34% Cremophor RH 40, 21.66% Transcutol. Globule size was found to be 25.42 nm, and zeta potential value was -9.26 mV. Prepared SNEDDS were evaluated for globule size, viscosity, emulsification time, cloud point, dilution test and thermodynamic stability study. Prepared liquid SNEDDS then converted into solid SNEDDS via extrusion/spheronization technique using Aerosil 200, lactose monohydrate and Croscarmellose sodium. The pellets containing SNEDDS possessed good flow properties and mechanical strength and other rheological parameters. Self nanoemulsifying pellet exhibited uniform size and shape. Friability, dissolution time and disintegration of pellets formulation shown promising results. Time required for 80% drug release of self nanoemulsifying pellet was found to be 26 min, which was significantly lower than liquid SNEDDS, plain drug containing pellet and marketed preparation of Allopurinol (ZYRIK).
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