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 oral therapeutic efficacy. The preparation of BNNLC involved the utilization of melt-emulsification and ultrasonication techniques, followed by optimization using Box-Behnken design (BBD). The independent factors in this study were the concentration of total lipids (A), surfactant (B), and sonication duration (C). The impacts of these variables were assessed on the dependent variables, namely particle size (PS, Y1) and entrapment efficiency (EE, Y2). The optimized BN nano-lipid carrier (BNNLCo) has shown a PS of 174.3 ± 5.4 nm, EE 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 was depicted that the formulation exhibited 3.2-fold higher intestinal flux than pure BN due to enhanced permeation across the tested membrane. The relative bioavailability results of BNNLCo displayed a significantly higher (4.27-fold) bioavailability as compared to pure BN. The highest reduction in swelling was obtained with the optimized formulation (71.78 % in 6 h) as compared to pure BN (46.65 % in 4 h) and standard drug indomethacin (65.76 % in 3 h). The effect of the formulation was sustained up to 12 h (51.54 %). Our findings concluded that incorporating BN in the NLC matrix could be an alternative system for the improvement of therapeutic efficacy.