The Hindustan Times reports a new use for women’s nail polish: as an indicator for the chemical rohypnol, commonly known as the “date rape drug.” The idea, said to be an invention of four students at North Carolina State University, is still in the development stage.
Interestingly though, the news does not appear to have made it into the common media outlets in North America. Perhaps they think that “date rape” is not a problem on this continent
The Drug
Flunitrazepam or rohypnol, CAS number 1622-62-4, and its close chemical relative alprazolam or xanax, CAS number 28981-97-7, are two of many compounds in the family of benzodiazepines. First developed over 50 years ago in Switzerland, both are psychotropic substances controlled under applicable laws in many western countries. Nevertheless, they appear to be readily available without much problem to people who intend to use them in despicable and illegal ways such as “date rape drugs.”
Of course, the drug’s relatively simple structures, shown below for flunitrazepam, would enable any skilled chemist to prepare it in short order. Presumably that’s what makes the drugs widely available on the black market. (Fig right. Chemical structure of flunitrazepam). 
The Effect
The drugs cause strong amnesia and were used several decades ago in hospitals when deep sedation was needed and they are still widely used for the treatment of sleep and anxiety disorders.
Combined with alcohol their amnesic effect is even more pronounced. Unfortunately, that also makes them so liked by people with bad intentions.
The Idea
The idea of using finger nail polish laced with an indicator that specifically detects these drugs is certainly elegant. Practically speaking though, I doubt the idea will lead to fewer rapes. The problem, as I see it is kinetics. In order to see an effect (such as, for example, a change in color of the nail polish) specificity, sensitivity, and reactivity to these drugs is required. Even if the first two conditions can be met, the third one requires a fast reaction that would not be available with a solid film of nail polish.














