While it's important for your dog or cat to have a form of ID in case they get lost, tags can fall off, and microchips can migrate out of place. Japanese scientists are developing an alternative, in the form of quick and painless tattoos.
First of all, yes, some pet owners do already get their animals tattooed. However, because the procedure is time-consuming, invasive and a bit painful, the creature typically has to be placed under general anesthesia beforehand.
Seeking a simpler approach to pet-tattooing, researchers from The University of Tokyo recently looked to what are known as microneedle patches.
In most cases, these devices take the form of a small, flat piece of material with an array of tiny, sharp, medication-filled studs – or "microneedles" – on its underside. While the main patch is usually made of a nontoxic polymer, the needles are made of a substance that will harmlessly dissolve once within the body.
When the patch is pressed against a patient's skin, the microneedles penetrate the skin's outer layer, not reaching any of the nerves beneath. Those needles soon dissolve, releasing the medication into the interstitial fluid between the skin cells.
For their patch system, the U Tokyo scientists utilized microneedles (less than 1 mm in length) made of hyaluronic acid, which occurs naturally in the body. These needles were loaded with molecules of nontoxic black tattoo ink. Additionally, the needles were arranged on each patch in such a manner that they formed a dot-matrix image of a specific letter or numeral.
In tests performed on rats, the microneedle patches were successfully used to tattoo such alphanumeric characters onto areas of bare skin. After a period of one month, those characters were still clearly visible to the naked eye.
More research still needs to be conducted, including longer-term testing. It is hoped that the technology could ultimately be used not just on pets, but also as a means of identifying livestock and tracking wildlife.
A paper on the study, which was led by Jongho Park, was recently published in the journal Scientific Reports.
And if you're thinking, "Hey, could microneedle patches be used to tattoo humans?" … well, scientists at Georgia Tech are already working on that.
Source: The University of Tokyo