Characterization and In-vitro Study of Metformin and Repaglinide Nano Emulsion in the Treatment of Diabetes

Repaglinide (RPG) and Metformin (MTF) are fast-acting glucose regulators that stimulate insulin release from pancreatic β-cells. Frequent dosing before meals is challenging. This study explores nanoemulsion as a promising carrier for RPG and MTF, aiming for sustained hypoglycemic effects. The drugs were incorporated into the oil phase, enhancing biopharmaceutical properties compared to traditional lipid-based systems. Formulations were chosen with a 5% w/w difference in oil content from the o/w nanoemulsion region. The optimized nanoemulsion to control nanodroplet size, ensure low viscosity, and incorporate distilled water. In vitro dissolution studies revealed that the nanoemulsion had higher drug release, finer droplet size, lower polydispersity, minimal viscosity, and excellent dilution capability compared to existing oral tablets. The optimized Repaglinide (RPG) and Metformin (MTF) nanoemulsion formulation demonstrated a superior hypoglycemic effect over the conventional tablet formulation.