Impact of Mixed Nonionic Surfactants on Self-Nanoemulsification Efficiency of Sefsol-218 in Glibenclamide Nanoemulsion

The aim of present study was to evaluate the impact of various combinations of nonionic surfactants on selfnanoemulsification efficiency of Sefsol-218 in glibenclamide nanoemulsion. Surfactants Labrasol, HCO-60, Tween-80, Cremophor-EL and Gelucire-44/14 along with cosurfactants Transcutol-HP, isopropyl alcohol and ethanol were investigated for this purpose. Formulations were prepared by spontaneous emulsification method and subjected for thermodynamic stability and self-nanoemulsification test. Only those formulations which were found to be stable at various stress conditions of thermodynamic stability and selfnanoemulsification tests were further characterized in terms of droplet size, viscosity, refractive index and % transmittance. Formulations prepared with Labrasol or Gelucire-44/14 were found to be suitable for self-emulsifying drug delivery system only whereas those prepared using HCO-60, Tween-80 and Cremophor-EL were found to be suitable for self-nanoemulsifying drug delivery system or selfmicroemulsifying drug delivery system. Based on lowest droplet size (39.1 nm), optimal values of polydispersity index (0.292) & refractive index (1.332), lowest viscosity (34.3 cp) and highest % transmittance (99.6), formulation S23 (Sefsol-218/Cremophor- EL/ethanol/water) was optimized as best formulation for self-nanoemulsifying drug delivery system of glibenclamide. These results indicated that Cremophor-EL could be the best surfactant in terms of self-nanoemulsification.