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The Sciences

Erasable Tattoos Work Like Scratch'n'Sniff

When a laser "scratches," dye microcapsules dissolve away.

By Morgen PeckNovember 16, 2007 6:00 AM
Microscopic beads that were produced with a red-brown iron oxide to create a red-brown ink.These microscopic beads are 5-6 microns in size and are suspended in solution. Images courtesy of Freedom-2, Inc. | NULL


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Tattoo ink company Freedom-2 has made it easier to erase bad body art. Using microencapsulation—technology found in scratch-and-sniff stickers—the company’s new ink allows for tattoo removal with a single laser treatment rather than the usual six or seven.

At Brown University, medical engineer Edith Mathiowitz encases molecules of water-soluble pigment within insoluble polymers. Applied to the skin, the compounds remain anchored, but when hit by a laser, they burst open and allow the body to reprocess the ink.

The FDA does not now regulate tattoo pigments, so the occasional harmful ink concoction travels to the lymph nodes and can complicate diagnoses of melanoma or induce allergic reactions. Standardized, high-tech inks like Freedom-2’s could make for a safer—and less regrettable—tattoo environment.

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