Nitration Surprise

(File under "Learn something new every day")

Boom goes the peptide!

For some light bedtime reading, I chose Life Technologies' Molecular Probes handbook, a 1,000-page opus of how to make anything and everything biological light up in brilliant hues of Texas Red or Cascade Blue. Flipping to Chapter 1, I quickly glanced at the very first scheme in the entire catalog, and did a double-take: tyrosine nitration...by tetranitromethane!

TNM: First time's the charm!
Source: Molecular Probes Handbook

Not to tread on Derek - who has a good thing going with his "Things I Won't Work With" tales - but doesn't this look like it should be grandfathered in to his list?

"Rule of Six" violation? Check. Potentially explosive byproducts? Check Check. A brief glance at the MSDS shows some of the more exciting Hazard Codes ("H330 - Fatal if Inhaled"), and the Merck Index (#9305) ain't much better: TNM "attacks iron, copper, brass, and rubber" and "Has been proposed as [an] irritant war gas."

Fun!

But, lest I lapse into my own fit of hypocritical chemophobia, I should point out that this compound is apparently 'par for the course' for stalwart chemical biologists - it's been used since the 1920s to label proteins, and a 1966 JACS article dubs it "stable, specific, and gentle." Even PubMed brings up >600 references, so I suppose my initial gut-check was a bit unwarranted - TNM looks OK when used in dilute solutions. But, I'd still say you should think twice before considering it for routine bench work.

"Hot Rocks" Cause Injury, Mystery

As reported on Yahoo / GMA (video), and by the ever-vigilant Jyllian Kemsley over at Safety Zone, a real-life chemical mystery is unfolding. A few days ago, a California couple strolled the beach with their kids, and pocketed a few interesting-looking rocks they had found. Later that evening, the rocks caught fire while in Lyn Hiner's pants pocket, with a "...bright, intense flame," that, according to reports, couldn't be patted or smothered out. The resulting fire hospitalized both wife and husband with severe burns.

Source: AP

So, the question remains: what was on the rocks? The orange substance, found on green and gray surfaces, may indeed be "phosphorous" [sic], as mentioned by a mildly chemophobic (nearby nuclear plant, firing range?!) Associated Press report. A local geologist commented that the orange coloration is "...not natural, it's human made." With some imagination, you could probably come up with a few phosphorus alternatives (looking at you here, ExploSci!).

Pyrophoric Metals - Finely dispersed powders of magnesium, zinc, or thermite could certainly react with a little acid or moisture. However, these don't fit the bill as "orange substances."


Flash powder - Often used in special effects and flares. This blend of oxidizers and reactive metals would have to have been intentionally placed on the rocks, since they wouldn't have remained stable for long, out in the open air.


Reactive Groups - Many organic groups react with violent decomposition or exotherms when sparked, touched, or heated. Although certainly far-fetched, someone fooling around with picrates, nitrates, or perchlorates could have inadvertently doped the stones in question. There's at least a few dozen of these salts around, and many (iron perchlorate, mercury fulminate, ammonium picrate) may actually be orange or yellow-colored.