Preparation and in vitro percutaneous permeation profile of glycyrrhetinic acid ethosome hydrogel patch

Objective To explore the preparation method of glycyrrhetinic acid ethosome(GAE) hydrogel patch and to evaluate its characteristics during in vitro transdermal drug delivery.Methods GAE was prepared by ethanol infusion method,and its entrapment efficiency,size and surface potential were investigated.Then GAE was used to prepare the hydrogel patch.The amount of penetrated glycyrrhetinic acid was determined by HPLC on modified Franz diffusion cells,and then the in vitro transdermal drug delivery of the prepared hydrogel patch was evaluated.Results GAE had a spherical or ellipsoidal appearance and a layered structure,with an encapsulation efficiency of(75.63±1.86)%,a particle size of(106.2±20.54) nm,and a surface potential of(-41.3±2.8) mV.The percutaneous delivery rate and accumulative infiltration quantity of GAE hydrogel patch were significantly higher than those of glycyrrhetinic acid hydrogel patch.The 24 h accumulative infiltration quantity of GAE hydrogel patch was 5.55 times that of the glycyrrhetinic acid hydrogel patch(t-test,P0.01).Conclusion Compared with glycyrrhetinic acid,GAE can significantly improve the in vitro transdermal delivery of hydrogel patch,demonstrating that ethosome hydrogel patch might be an ideal vector for transdermal delivery of glycyrrhetinic acid.