Tattoo ink can't be autoclaved; the excessive heat would ruin it. However, it should be sterile and here's how:

The FDA does not approve or certify the tattoo ink in the U.S. However, a number of reputable ink suppliers exist and any good tattoo artist will obtain his or her ink (and other supplies) from such a source. Regardless of the source, the ink should be composed solely of materials that are safe to use for tattoos. In ohter words, tattoo ink should be made of substances that don't cause allergic reactions, that are not carcinogenic, and they are manufactured in a sterile environment.

The sterility of tattoo ink is assured by the following:

The ink is composed of substances that prevent bacterial or fungal growth. Some use ink infused with Witch Hazel, a natural antiseptic. Some tattoo artists use ink that contains alcohol to ensure sterility (some use Vodka.) Proper tattoo ink does not contain anything that bacteria or fungus could live off: no sugar or protein. Also, the pigment in modern tattoo ink is not organic and thus does not break down over time. All these things prevent tattoo ink from “spoiling.”

Second, proper tattoo ink is manufactured in a sterile environment by an approved company. The ink is sold in two forms: pre-mixed and powder. I suggest the use of pre-mixed ink, which is delivered in a usable form in a sterile container. The ink, the carrier (purified water) and any additives (such as an antiseptic) were sterile to begin with and have been mixed in a sterile environment. This ink is ready to use right out of the box.

In the case of powdered ink, the artist receives just the finely powdered pigment and then mixes it himself or herself. This process requires quite a bit of work, great care, and a variety of sterile ingredients and equipment. I’m sure that there are some shops and artists who mix their own ink and end up with a perfectly usable and clean product. For me, though, there seems to be too much room in this process for error.

The last part of keeping ink sterile is up to the artist himself/herself. The artist will keep tattoo ink in closed containers in a clean area. Most artists I’ve seen use small squeeze bottles with tight fitting caps. Ink does not need to be refrigerated. The artist will always handle the ink containers with gloves on. Finally, the artist will not use ink directly from the storage containers but will dispense it into a tiny cup first. The cups are disposable, never re-used, and are also stored in a clean environment such as in an airtight container or a closed plastic bag. (This little cup is sometimes called an “inkpot.”) This ensures that a tattoo needle with someone’s blood on it makes contact only with a small amount of the ink and not with the entire supply, thus preventing any cross-contamination from client to client. Finally, and this should be a no-brainer, any ink that is left over in the inkpot is thrown away at the end of the session along with the tattoo needles.m