Formulation, characterization and optimization of folic acid-tailored daidzein solid lipid nanoparticles for the improved cytotoxicity against colon cancer cells

Objective: The study aims to formulate and optimize daidzein-conjugated folic acid solid lipid nanoparticles (DZN-FA SLNs) to improve bioavailability and target site specificity for the treatment of colon cancer, a significant global health concern associated with high morbidity and mortality. Methods: DZN-FA SLNs were prepared using the microemulsion method. They were prepared and optimized using design expert software. Physicochemical characterization like differential light scattering (DLS), Fourier transformed infrared spectroscopy (FTIR), scanning electron microscope (SEM), In vitro drug release and In vitro cell line studies and accelerated stability studies were carried out in the optimized batch formulation. Results: The results indicated that particle size for optimized DZN-FA SLNs was in the range of 212 to 620 nm, zeta potential of-20 mV, drug entrapment efficiency of 72%. In vitro drug release for the prepared formulation showed 53% over 48 h. Conclusion: The optimized DZN-FA SLNs could aid in a better formulation targeting colon cancer cells, thereby reducing systemic effects. The optimized DZN-FA SLNs have demonstrated excellent inhibitory properties on Caco-2 cells, with an IC50 value of 10 µg/ml, offering a promising innovation in cancer treatment by providing targeted and effective therapy for colon cancer while minimizing the impact on normal cells.