Development and optimization of kaempferol loaded ethosomes using Box–Behnken statistical design: In vitro and ex-vivo assessments

Kaempferol (KMP) belong to flavonoid class have developed in ethosomal formulation and were evaluated for their potential to treat diabetic foot ulcers. Even though ethosomes are highly deformable, they can pass through human skin intact. KMP ethosomes were formulated using the cold method and optimized by Box–Behnken design (BBD) (three-factor, three-level (3³)). The formulation variables used for optimization are drug concentration of KMP, soylecithin content, and ethanol percentage. The optimized formulation was examined using transmission electronic microscopy (TEM), differential scanning calorimetry (DSC), Fourier transform infrared (FTIR) spectroscopy, in-vitro release, ex-vivo permeation studies, and storage stability. The optimized KMP ethosomes was found to have vesicle size (VS) of 283 ± 0.3 nm and zeta potential (ZP) of −29.67 ± 0.3 mV, polydispersity index (PDI) of 0.36, % entrapment efficiency (%EE) of 91.02 ± 0.21%, drug loading (%) of 46.23 ± 2.5% followed by good storage stability at 4°C/60 ± 5% RH. In vitro drug release of optimized KMP ethosomes was 88.2 ± 2.75%, which was approximately double when compared with pure KMP release, that is 49.9 ± 1.89%. The release kinetics for optimized KMP ethosomes follows the Korsmeyer–Peppas model. An apparent permeation coefficient of 356.25 ± 0.5 μg/cm² was determined and compared with pure KMP (118.46 ± 0.3 μg/cm²) for 24 h. According to the study, ethosomes can be a cutting-edge strategy that offers a new delivery method for prolonged and targeted distribution of KMP in a variety of dosage forms including oral, topical, transdermal, and so forth.