Preparation And Properties Investigation Of Quercetin Loaded Nanocapsules

Quercetin which is a flavonoid molecule and widely existed in nature behaves numerous biological activities, including antioxidant, anticancer and anti-inflammatory activities, but its poor stability and aqueous solubility significantly limit its wide application in the fields of food, medicine and chemical industry. At present, most of the methods for improving the solubility of quercetin are complex, time consuming and harmful to the body. Therefore, it is urgent to develop a simple, low-cost and green method to improve the bioavailability of quercetin.In this work, we combined the advantages of membrane ultrasound and electrostatic deposition method, and proposed a method for the synthesis of highly dispersed quercetinliposome-chitosan nanocapsules. The prepared nanocapsules were characterized by scanning electron microscope, UV/Vis spectroscopy and Fourier transform infrared spectroscopy, and the embedding rate of quercetin(EE%) was further evaluated. Based on that, the relative stability and antioxidant activity of natural quercetin and Q-NPs were compared. Moreover,the MTT colorimetric method and the trypan blue exclusion assay were used to evaluate the anticancer activity of Q-NPs.The results show that the EE% of Q-NPs is about 80%, the surfaces of the Q-NPs are relatively smooth, and Q-NPs at the size of 600 nm are spherical. UV/Vis spectroscopy and Fourier transform infrared spectroscopy revealed that quercetin was successfully encapsulated into chitosan coated liposomes. The stability test showed that the stability of quercetin was significantly increased after the inclusion of quercetin into the nanocapsules. Antioxidant research showed that Q-NPs had similar DPPH free radical scavenging ability with the native quercetin in the system of ethanol and Q-NPs had much higher scavenging hydroxyl free radical, superoxide anion and ferricyanide reducing power than the native quercetin in the system of water. Moreover, at the concentration of 10 μg/m L, treatment with Q-NPs significantly reduced the cell viability by 59.08%, while only 53.33% was reduced by nativequercetin at the same concentration, which indicated that Q-NPs possessed stronger cancer cell killing ability than that of native quercetin.The method proposed in this research is easy-handled, cost-effective and green thus provided some novel minds for further development and utilization of quercetin. It can also provide some reference for other hydrophobic functional factors of the preparation of nanocapusles.