N-trimethyl chitosan coated targeting nanoparticles improve the oral bioavailability and antioxidant activity of vitexin.

Vitexin is a flavonoid which exerted many protective activities. However, the low bioavailability discounts the in vivo effects of vitexin. This study designed vitexin loaded bilayer nanoparticles by the assembly of soybean peptides and the coating of goblet cell targeting peptide CSKSSDYQC (CSK) coupled N-trimethyl chitosan (TMC), to improve the bioavailability of vitexin. The results showed that the bilayer nanoparticles could protect vitexin from being released in stomach and promote sustained release in intestine. Ex vivo experiments confirmed that nanoparticles promoted absorption of vitexin through tight junctions. Further in vivo studies suggested that the embedding of vitexin by nanoparticles increased the bioavailability and antioxidant activity of vitexin. Our results indicated that the nanoparticles could not only promote the absorption of vitexin, but also improve its in vivo antioxidant activity. Therefore, the reported nanoparticles could be effective delivery platforms to improve the bioavailability of vitexin.