Evaluation of solubility and dissolution of lamotrigine using lipid based microparticulate carriers: An in-vitro analysis.

The present study was designed to develop novel lipid microparticles in order to improve solubility, dissolution and bioavailability of a lipophilic drug of BCS class II, lamotrigine. For that purpose, increase in solubility of the model drug was investigated using different lipids and the promising lipids were further used for the fabrication of microparticles. Solid lipid (GMS) and liquid lipid (olive oil) were used along with an emulsifier (Tween 80) and a stabilizer (Poloxamer 188) to prepare mircoparticles by melt emulsification method. Prepared formulations were characterized for physicochemical properties such as solubility, particle size, zeta potential, polydispersity index and entrapment efficiency. In vitro dissolution studies were carried out in 0.01 N HCl for 24 h. The findings provided that the solubility of lamotrigine was reasonably increased in GMS, olive oil, Tween 80 and poloxamer 180. The lamotrigine solubility was increased 4.92 fold with G4 microparticles formulation. Size analysis revealed that the microparticles were in range of 11.1 to 178.8 μm and the zeta potential values were from -13 to -20 mV. Microparticles prepared with solid and liquid lipids exhibited satisfactory entrapment efficiency ranging from 59 to 87%. Conclusively, the outcomes of the studies suggest the appropriateness of selected ingredients for improving solubility as well as loading of lamotrigine in microparticles for its sustained and effective delivery.