Enhancement of aqueous solubility of icariside II through complexation and addition of Tween 80 and lecithin

Abstract Natural drug products with limited water solubility pose a challenge to the pharmaceutical industry in terms of developing an appropriate dissolution procedure. Like other flavonoids, icariside II (ICS) also faces challenges such as insufficient bioavailability caused by its poor water solubility, limiting its oral therapeutic applications as a food supplement. Consequently, new approaches are needed across the board focusing on the aqueous solubility enhancement. This work aimed to use whey protein concentrate (WPC) as a carrier, and surfactants such as Tween 80 and lecithin to improve the water solubility of icariside II. The complexation with WPC successfully increased the water solubility of ICS by approximately 258-fold. Furthermore, the incorporation of surfactants into the complex resulted in an even greater enhancement, achieving a 554-fold improvement. In addition, by repurposing of whey protein complexes, a byproduct generated during cheese production, and the application of efficient solvent recovery methods, we illustrate our dedication to sustainability. Fourier transform infrared spectroscopy; X-ray powder diffraction and differential scanning calorimetry indicated the successful complex formation procedure. Using a scanning electron microscope, the morphology of the product was analyzed. To the best of our knowledge, no studies have yet produced and investigated the aqueous solubility of mixed surfactant-based icariside II whey protein complexes (S-ICS-WPC).