Evaluation of Stability and In vitro Anti-Cancer Activity of Dihydroquercetin Nanoemulsion

Background: Dihydroquercetin (DHQ), also known as taxifolin, is a flavonoid commonly found in many plants. Dihydroquercetin has been documented to have powerful antioxidant activity and many beneficial properties for human health, especially its ability to inhibit certain types of cancer cells. However, its low solubility and bioavailability are major obstacles to biomedical applications. Moreover, DHQ is chemically unstable and quickly degrades when exposed to alkaline conditions. Objective: In the present study, a DHQ nanoemulsion formulation was prepared by Self Nano- Emulsifying Drug Delivery System (SNEDDS) technique to overcome the above disadvantages. Methods: The obtained nanoemulsion system was evaluated for its micro-properties, stability, and in vitro cytotoxic activity against some cancer cells using tetrazolium dyes (MTS assay). Results: Measurement results showed that the DHQ nanoemulsion was successfully synthesized with typical mean droplet sizes from 9 to 11 nm, and revealed excellent stability over time. Dihydroquercetin in nanoemulsion form is more stable than the non-encapsulated form, as evidenced by the maintenance of droplet size in the nanometer range when dispersed in aqueous solution for up to 48 hours. This stability is particularly pronounced in both acidic and neutral environments. In vitro experiments on cytotoxic activities against A549, Hela, and HepG2 cancer cell lines indicated that the prepared DHQ nanoemulsion effectively inhibited the growth of all these cell lines with IC50 values (μg/mL) of 8.0, 20.4, and 29.5 respectively. Conclusion: From the detailed results above, it is evident that the solubility and bioavailability of DHQ can be improved by creating its nanostructure in the form of nanoemulsions. Furthermore, the nano form of DHQ carried within stable nanoemulsions exhibited better performance in inhibiting cancer cells compared to free DHQ. Therefore, further research is required to explore the development of cancer therapeutics utilizing nano DHQ emulsions.