Preparation and characterization of glycyrrhetinic-acid loaded PEG-modified liposome based on PEG-7 glyceryl cocoate

The aim of the study was to develop a kind of glycyrrhetinic acid (GA) liposome modified by PEG-7 glyceryl cocoate for cosmetic use. Encapsulation efficiency, particle morphology, particle size, zeta potential, and Fourier transform infrared spectroscopy (FTIR) were studied to get its physico-chemical properties. Release property, skin permeation in vitro, and storage stability were also investigated to evaluate the application performance. The results showed that the PEG-modified liposomes were spherical particles with mean particle size of 117 +/- 4.6 nm. Zeta potential and average encapsulation efficiency were -22.5 +/- 0.54 mv and 91.9 +/- 2.43%, respectively. The FTIR results indicated that GA had been loaded successfully into the liposomes. Compared with the non-PEG-modified liposomes, the PEG-modified GA liposomes showed lower release rate and higher deposition in epidermis/dermis in vitro study, and also possessed better stability according to the little change of particle size during 30 days.