The resulting zeta-potentials of nano-emulsions with different squalene concentrations listed in Table 1 are given in Fig.6.The droplets of the nano-emulsions were negatively charged. The zeata potential was -65.1mv for formulation (i) and increased dramatically to -101.8mV for formulaton(iv)as shown in Fig. 6. The stabiliy of the emulsion could be increased by expanding the surfact flocculation (Liu et al.,2006). In the system studied,it was revealed that the surface charges of the droplets increased as the squalene percentage increased (Table 1). The negative charges on the surface of VCO droplets covered with EK were the result fo tho adsortion of OH-ions on the o/w interface through hydrogen bounding.