[mochaccino]

The best chemical for topical penetration might be DMSO, but it's very strong so you have to be careful, and only use it in small amounts. It's apparently so effective at carrying things through the skin that it can carry bacteria into your bloodstream along with any soaps, lotions etc. that were never intended to be absorbed so deeply. I started out by using hyaluronic acid, but then I realized that DMSO is much cheaper and whole lot more effective.