Formulation Development of Solid Dispersion Prepared by Newer Approach:A Research

Hot melt extrusion is the most widely applied technique of solubility enhancement, includes complex mixtures of API, plastisizers and polymer carriers which are passed through single or twin-screw extruders at high temperature and stress. Present investigation deals with enhancement of dissolution rate and hence solubility of Lamotrigine, belonging to BCS class II, used primarily for treatment of Epilepsy. Copovidone as polymer and polyethylene glycol, polyoxy 35 castor oil and sorbiton monolaurate as plasticizers were used. Evaluation techniques like saturation solubility, effect of temperature on preparation of complexes, differential scanning calorimetry, x-ray diffraction, Infra red, dissolution and in vitro permeability studies were carried out. X-ray diffraction concluded that hot melt extrusion process demolished the sharp peaks of lamotrigine indicating complete conversion of crystal form to amorphous form. Dissolution and solubility studies showed enhancement in release rate. Stability studies at 40 °C/75 % RH were studied, samples were found to be stable even after 3 months study.