Cubosomal nanoformulation increase in vitro dissolution and anticancer activity of Fisetin in A549 lung cancer cells

Aim: To prepare fisetin (FIS) cubosomal nanoformulation to increase aqueous solubility and anticancer activity. Methods: Top-down method using glyceryl monooleate (GMO) and Pluronic F-127. Results: Optimized using 2% GMO and 1% Pluronic F-127, reported 93.07 nm particle size, 80.10% drug entrapment, and reports more than 50% enhanced in vitro drug release than native FIS. MTT assay reports IC50 Values of FIS 16.59 μg/ml and optimized cubosomal FIS nanoformulation (FISCUB) 12.18 μg/ml. The colony numbers observed in clonogenic assay for FISCUB were 8.33 ± 0.58 and FIS 11.67 ± 1.15. In flow cytometry study, apoptotic cells in FISCUB and FIS-treated A549 cells were found to be 33.4 and 6.83% respectively. Conclusion: A stable cubosomal nanoformulation of FIS showed enhanced aqueous solubility and anticancer activity. Fisetin (FIS) is a plant secondary metabolite from the class of flavonoids reported promising therapeutic potential. It possesses the problem of low aqueous solubility and bioavailability that restricts its utilization of maximum therapeutic benefits against its anticancer and other uses. The solubility and bioavailability issue can be solved using nanoformulations and many researchers have reported novel nanoparticulate drug-delivery systems and other phytoformulations. Using a top-down method, we prepared and optimized a novel FIS cubosomal formulation, which is a liquid dispersion of crystalline cubic nanoparticles of an amphiphilic lipid glyceryl monooleate. The Design expert® software, a 32-full factorial design was used for optimization. The particle size, entrapment efficiency, viscosity, pH and polydispersity index were tested. The previously reported HPLC analytical method was used for FIS estimation. The cubosomal formulation batch B2 prepared using 2% lipid (GMO) and 1% Pluronic F-127 was an optimized batch. High-resolution transmission electron microscopy and x-ray diffraction study were performed for the cubosomal particle characteristic study. In vitro release study confirms that the FIS release was more in the prepared cubosomal formulation. In the 3 month stability study, optimized batch B2 was found to be stable after 3 months. We observed transmission electron microscope images and confirmed the cubic structures of particles present in the nanorange concerning their size. The in vitro study of the optimized cubosomal formulation was carried out to study the effect of cubosomal formulation on cellular absorption and cytotoxicity studies. In the in vitro study, MTT, Clonogenic, Flow cytometry assay, and acridine orange-ethidium bromide staining were performed. The optimized cubosomal formulation reported more cytotoxicity results than the native FIS. In the FIS cubosomal nanoformulation study, we have prepared, and optimized cubosomal FIS nanoformulation with a simple procedure and a smaller number of ingredients for better delivery of fisetin.