Application of Box-Behnken design for the optimization of Plumbago zeylanica extract-loaded niosomes: preparation, characterization and in vitro antidiabetic and antioxidant activity

This study aimed to develop and evaluate a niosomal formulation loaded with Plumbago zeylanica extract (PZE). The solvent evaporation method was used to prepare niosomes and optimized using the Box-Behnken design. The optimized formulation (PZE-Ns-Opt) was characterized for drug release, DPPH assay, alpha-amylase inhibition assay, alpha-glucosidase inhibition assay, and confocal laser scanning microscopy (CLSM) study. PZE-Ns-Opt showed a vesicle size of 253.6 nm, PDI of 0.108, entrapment efficiency of 62.4%, and drug release of 84.01%. The CLSM image of the rat's intestine suggested that the rhodamine red B-loaded PZE-Ns-Opts showed superior penetration compared to the control. Further, the antioxidant activity of the prepared formulation was exhibited as 89.46%+/- 0.016 as compared to PZE (78.10%+/- 0.005). In addition to this, alpha- amylase activity was inhibited by 95.11%+/- 4.62, 85.88%+/- 2.56, and 89.87%+/- 3.65 by acarbose, PZE, and PZE-Ns-Opt, respectively. In comparison, the alpha-glucosidase activity was inhibited by 88.47%+/- 1.04, 81.07%+/- 0.50 and 85.78%+/- 0.71 by acarbose, PZE, and PZE-Ns-Opt, respectively. To conclude, the development of PZE-Ns-Opt formulation and its characterization showed the establishment's authenticity. The in vitro antidiabetic, antioxidant studies expressed the protective effect from oxidative stress, CLSM of rat's intestine ability to penetrate to great extent and could be a promising candidate for the management of diabetes mellitus. [GRAPHICS] .