ELECTROPHORETIC MOBILITY OF SOME TATTOO DYES 297 color intensity of the black pigment becomes weaker after the electrophoresis. It is quite obvious because some portions of the dye were migrating away from the sample, so its concentration and coloring intensity should decrease. DISCUSSION Al l tested ta ttoo samples have revealed the negative zeta potentials, although their values were suffi cient to maintain quite signifi cant mobility of the dye grains inside the faux skin samples. The margin between colored and not-colored gelatin samples has moved for about 10 mm after 40-min-long application of the 20–25 V potential difference. These results prove that the method presented in this work looks quite promising for elimination of the old or unwanted tattoos alone or in combination with the others. In the latter case, it should be used at the fi nal stage to eliminate the residual traces and shadows of the tat- toos. Low voltages and comparatively short application time tested in the framework of present investigation allow one to expect that the volunteer requesting the removal of the tattoo should not experience serious discomfort because of local skin overheating during the treatment. However, a series of thorough experiments is recommended with tattooed animal skin to determine the exact regimes of electrophoresis before testing this approach on human volunteers. This result p romises potential applicability of this method in technologies of elimination of old, blurred, or unwanted tattoos. Figure 4. Mobility o f the black dye particles after the 2,400-s electrophoresis. Left, before right, after elec- trophoresis. The boundary has shifted for approx. 10 mm. Figure 5. Mobility of the black dye particles after the 2,400-s electrophoresis. Left, before right, after elec- trophoresis. The boundary has shifted for approx. 8 mm.

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