Formulation Design and In vitro Evaluation of Berberine- Loaded Self-Nanoemulsifying Drug Delivery System

Purpose: To improve the oral bioavailability of berberine using a new self-nanoemulsifying drug delivery system (SNEDDS).
Methods: Berberine SNEDDS was designed using solubility studies and phase diagram construction. A series of tests were carried out to study the effect of oil content, dilution, and drug loading on particle size. The morphology of the nanoemulsion was examined with a transmission electron microscope. Subsequently, the optimized berberine SNEDDS was investigated for in vitro release and compared with two marketed products (Xiaowei capsules and Beike tablets)
Results: The optimized formulation, composed of berberine of 6.0 %, castor oil of 18.8 %, Tween 20 of 37.6 %, and glycerol of 37.6 %, gave a mean particle size of approximately 60 nm, and was not affected by dilution. The optimized formulation released 90 % berberine in 20 min, while the reference products, Xiaowei capsules and Beike tablets, required 2 h to release 90 % of berberine.
Conclusion: The optimized formulation of SNEDDS is a potential alternative oral dosage form for improving oral absorption of berberine.

Keywords
Berberine; Pseudoternary phase diagram; Self-nanoemulsifying; SNEDDS; Drug release