Having a good time with Uncle Billy Bob sometimes means making bootleg moonshine in the basement. You can trust that his alcohol is safe because Uncle Billy Bob is an honest guy. (Well, mostly honest, anyway. It's illegal to distill your own spirits in the U.S., mainly for tax reasons. That's how the federal government rolls.) But, you certainly don't need to worry about going blind from drinking Uncle Billy Bob's hooch.

That's not true for all hooch, however. The alcohol we love to imbibe is referred to chemically as ethanol; but dishonest bootleggers can spike their drinks with methanol, a.k.a. "wood alcohol." At first, it makes you feel drunk, just like ethanol. But later on, the methanol hangover is decidedly nastier: You can go blind and/or die. And in 2012, about 40 people died after they drank bootleg Czech alcohol. Unfortunately, there aren't a lot of convenient ways to determine if the adult beverage you purchased in the underground economy is going to kill you.

Now, Japanese scientists report in the American Chemical Society's journal Applied Materials & Interfaces the development of a novel material which changes color in the presence of toxic methanol, but not ethanol. (See figure.)

The material is rather complex, as it consists of a layered double hydroxide (basically, a structure with alternating positive and negative layers) adsorbed to oxoporphyrinogen (OxP). This film is normally colored magenta, and in the presence of ethanol (EtOH), it does not change color. But, in the presence of methanol (MeOH), it becomes purple. Therefore, if your black market booze turns this film purple, then you would be smart not to drink it.

The authors hope that their discovery can eventually be developed into a "test paper" -- much to the relief of moonshine lovers worldwide.

Source: Shinsuke Ishihara et al. "Naked-Eye Discrimination of Methanol from Ethanol Using Composite Film of Oxoporphyrinogen and Layered Double Hydroxide." ACS Appl. Mater. Interfaces 5 (13): pp 5927–5930. (2013) DOI: 10.1021/am401956s