Study On Quercetin-loaded Chitosan Nanoparticles For Skin Topical Use Against Ultraviolet B Radiation

In recent decades,people suffer more and more ultraviolet radiation owing to the depletion of ozone.Ultraviolet radiation especially solar ultraviolet-B(UVB)can induce photoaging,melanin pigmentation,photosensitive skin diseases,edema,inflammation and even skin cancer.Quercetin(Qu),one of flavonoid family members which produced by natural plants,has showed protective effects against UVB radiation.However,its application for topical use is limited by low hydrophilicity and poor percutaneous absorption.A series of attempts have been made,like chemical modification,entrapment by liposome and PLGA-TPGS nanoparticles.But these methods are all have their drawbacks including side effects,poor biocompatibility and high cost.Chitosan(CS),a homoglycan of glucosamine linked by β-1,4-glycosidic bond,which derived from chitin,a substance abundant in nature,by deacetylate.CS has high biocompatibility,which perform no biotoxicity and can be absorbed by organism.Further more,CS,a cationic polymer,has strong biological adhesion and can adhere to cytomembrane and stratum corneum which have negative surface charge.Thus,CS can be used as carriers for drug delivery.Herein,we found that Qu,if entrapped into TPP-Chitosan nanoparticles(TCs),can be efficiently uptake by Ha Ca T cells and easily permeate through the epidermis layer,meanwhile display better stability and low cytotoxicity.We also found that Qu-loaded TCs(QTCs)could notably enhance the effect of Qu on inhibiting the NF-k B/COX-2 signaling pathway as well as ameliorating the skin edema and inflammation caused by UVB radiation.Therefore,this study provided a method to get rid of Qu’s low hydrophilicity,enhance its percutaneous absorption and retention in the skin,and further improve its anti-UVB effect,and demonstrated that Qu-loaded chitosan nanoparticles can be used as the therapeutic agent for topical use against UVB radiation.In the mean time,we verified that the feasibility of chitosan nano-drug delivery system for skin topical use.