Encapsulation of Polyphenols from Lycium barbarum Leaves into Liposomes as a Strategy to Improve Their Delivery

This study is focused on the encapsulation of polyphenols from Lycium barbarum leaves into liposomes as a strategy to improve their delivery. Liposomes loaded with Lycium barbarum leaves extract were obtained and characterized for particle size, polydispersity, entrapment efficiency, and stability. Liposomes presented entrapment efficiency higher than 75%, nanometric particle size, narrow polydispersity, and good stability over three months at 4 °C. The liposomes containing Lycium barbarum offered a slower release of polyphenols with attenuated burst effect compared with the dissolution of free Lycium barbarum extract in phosphate buffer solution at pH 7.4. Moreover, an in vitro pretreatment of 24 h with loaded liposomes showed a cytoprotective effect against H₂O₂-induced cytotoxicity on L-929 mouse fibroblasts cells. These preliminary findings imply that liposomes could be successfully employed as carriers for polyphenols in pharmaceutical applications.