responses. A 3-D mesh plot and contour map was drawn to point out the main effects of temperature and pH on the AA-2G.
The HPLC analytical method was a good tool for chemical analysis. Although AA-2G was mixed in cosmetic lotion to serve as an active ingredient, using HPLC could effectively separate AA-2G from other components. A representative chromatograph of AA- 2G analysis is shown in Figure 2. Peak A was AA-2G whose retention time was 3.046 min. Peak B was gallic acid which was the internal standard. Based on Figure 2, AA-2G was successfully separated from the cosmetic lotion.