Self-Nanoemulsifying Drug Delivery System to Enhance Solubility and Dissolution of Lipophilic Drug Repaglinide

Abstract

Introduction: Self-nanoemulsifying drug delivery systems (SNEDDSs) are isotropic mixture of oil, surfactant,
cosurfactant, and drug that form fine oil in water emulsion when get contact with water on mild agitations. This
property renders the SNEDDS into perfect drug delivery systems to deliver Biopharmaceutics Classification
System Class II drugs with enhanced solubility. Materials and Methods: The SNEDDSs have different
preparation methods, classified as high-energy method and low-energy methods. In low-energy method, phase
inversion method or standard admixture method using vortex mixture was used to prepare formulations using
various oils and surfactants. Results: Solubility of repaglinide was carried out in different vehicles; we observed
that high solubility was found in neem oil (45 mg/mL), Cremophor RH 40 (21 mg/mL), Transcutol (48 mg/mL),
and Span 80 (34 mg/mL). Ternary diagrams were drawn for oil:Smix ratios which were clear emulsion observed.
From the phase diagrams, ratios possessing high oil percentage were considered, F1 to F7 formulation ratios were
selected. All formulations were subjected to evaluation tests with no phase separation, no precipitation. F1 and
F7 formulation has shown high in vitro drug release when compared with other formulations by forming nanosize
particle 223 nm and 221nm, respectively. Conclusion: Repaglinide SNEDDSs have shown 157% increase in
in vitro dissolution data when compared to marketed formulation.