Bergenin nano-lipid carrier to improve the oral delivery: Development, optimization, in vitro and in vivo evaluation

This study aimed to prepare bergenin (BN) loaded nanostructured lipid carrier (NLC) to improve therapeutic efficacy. BNNLC was prepared by melt-emulsification and ultrasonication methods. Further, it was optimized by Box-Behnken design. The concentration of total lipids (A), surfactant (B), and sonication time (C) were used as the independent variables, and their effects were evaluated on the independent variables as particle size (Y1) and entrapment efficiency (Y2). The optimized bergenin nano lipid carrier (BNNLCo) has shown a particle size of 174.3 ± 5.4 nm, entrapment efficiency of 80.6 ± 1.92 %, polydispersity index (PDI) of 0.086 and zeta potential of -35.6 ± 3.61 mV. The solid-state characterization results showed that BN was completely encapsulated into the NLC matrix. The BNNLCo exhibited a significant (p<0.05) sustained release (74.2 ± 3.9 %) than pure BN. The Korsmeyer-Peppas model (R2=0.9326) was found to be the best-fit kinetic model. Further, it depicted 3.2-fold higher intestinal flux than pure BN due to enhanced permeation across the tested membrane. The in vivo relative bioavailability and anti-inflammatory study results displayed a significantly higher 4.27-fold bioavailability and also a reduction in hind paw swelling (65.37%) than pure BN. Our findings concluded that incorporating BN in the NLC matrix could be an alternative system for the improvement of therapeutic efficacy.