The 18β-glycyrrhetinic acid (NGA) nanocrystals prepared by adsorption of amphiphilic chitosan (ACS) with 10:1 optimal ratio of NGA to ACS was used to prepare ANGA composites, which was utilized to prevent and treat skin photoaging. The results of this article indicated that the NGAs could significantly enhance the photoaging of mouse skin, so the ANGA hydrogel could be used to counteract skin photoaging.

The shape of the ACS coated NGA nanoparticles were studied by?SEM?characterization after completely drying under vacuum and fixing on a conductive tape. The SEM images of the sample coated with gold for 2 min using Vac Coat DSCR?sputter coater, under an excitation voltage of 5 kV, is shown below.