Figure 3: The change in the zeta potential as a function of the molar ratio of CO32- to Mg2+ (XCO). The concentrations of α-lipoic acid and polyoxyethylene (20) stearyl ether are fixed at 1% and 2%, respectively. The molar ratio of Mg2+ to α-lipoic acid (XMg) is fixed at 0.5. Data represent the mean ± S.D (n=3).