Study of cosurfactant effect on nanoemulsifying area and development of lercanidipine loaded (SNEDDS) self nanoemulsifying drug delivery system

In vitro release studies in USP II apparatus indicate significant improvement ( p < 0.001) in dissolution of lercanidipine from SNEDDS (F4) over marketed tablet “Zanidip” (10 mg) and plain lercanidipine in different dissolution media. [Display omitted] ► In phase diagram, effect of cosurfactants on the nanoemulsifying area was proved. ► Length of hydrophobic alkyl chains in cosurfactants defines emulsification capacity. ► Careful selection of cosurfactant is required for effective nanocarrier based system. ► Smix ratio of 3:1 gave best self-nanoemulsifying lercanidipine loaded formulation. ► Results of 3 months stability studies indicated no significant change in parameters. ► SNEDDS increased in vitro release of drug than marketed tablet and plain drug. The present study deals with the development and characterization of self-nanoemulsifying drug delivery system (SNEDDS) to improve the oral bioavailability of poorly soluble third generation calcium channel blocker lercanidipine (LER). Solubility of the LER was estimated in various oils, cosurfactants and surfactants which were grouped into two different combinations to construct pseudoternary phase diagrams. Various thermodynamic stability and dispersibility tests were performed on the formulations from phase diagram. After constructing phase diagram of two different combinations NL-I and NL-II, the effect of cosurfactants on the nanoemulsifying area was studied and the effect of number and length of hydrophobic alkyl chains of cosurfactant in its emulsification capacity was proved. Percentage transmittance, emulsification time, viscosity and droplet size analysis were used to characterize optimized formulations. The optimized formulation composed of Cremophor EL (45% wt/wt), (13.5% wt/wt) Caproyl 90 with (1.5% wt/wt) Transcutol® HP as per limits of inactive ingredients guidelines of FDA and Maisine oil (10% wt/wt). The mean droplet size in selected nanocarrier system was 20.01 nm. The in vitro dissolution profile of LER SNEDDS was found significant in comparison to the marketed LER (Zanidip) tablet and pure drug in pH 1.2, 4.5 and 6.8 buffers. Empty hard gelatin capsule shells were filled using Pfizer's Licap technology and charged on stability conditions of 30 °C/65% RH, 40 °C/65%RH and 50 °C/75% in glass bottles where no significant degradation ( p > 0.05) was observed in 3 months. The results indicate that SNEDDS of LER, owing to nanosized, has potential to enhance the absorption of drug.