Super-Sensitive Spray-On Explosive Detector

esocid writes "US scientists have designed a new spray-on explosive detector sensitive enough to detect just a billionth of a gram of (nitrogen-containing) explosive. After treatment, the explosive glows blue under UV light, making the detector perfect for use in the field. The silafluorene-fluorene copolymer can detect explosives at much lower levels than existing systems because it detects particles instead of explosive vapors, and is able to show the difference between nitrate esters (trinitroglycerin) and nitroaromatic explosives (TNT). The team is currently working on a similar system to detect peroxide-based explosives and say they hope to be able to investigate perchlorates and organic nitrates, too."

Comments

Won't this creat a lot of false positives?

[iminplaya]

95% percent of our paper money contains microscopic amounts of cocaine, imagine if we use such sensitive equipment to detect it. We'd all be locked up. Mmmm...maybe that's the intention.

Re:Won't this creat a lot of false positives?

[TheCarp]

> Sure, terrorists could never get it all off themselves, but then neither could
> anyone else.

Are you sure?

Actually I think the terrorist has the best chance. So they adopt clean room style techniques to separate production of explosives from packaging them. Produce the explosives, produce the other componenats. seal them in a plastic layer... hand off to a clean person at the door who takes it to a clean room, tosses it in a tub to be washed, and leaves it to the next guy who has never been to a room full of explosives with all clean clothes to sew it into a bag or other operation.

They can even do test runs where they just test moving something innocuous that they bag up and try to fly with and see if it picks up residue. As long as it looks like a false positive, they get their information.

I don't really think any number of technological measures will ever stop a determined attacker who can choose his methods and his time.

-Steve

I lost faith in the current system

[Groo Wanderer]

I lost faith in the current airport explosives detectors when I found out that Bondo products set them off. It was a hilarious hour or so watching a broken system thrash about trying to figure out why their machine kept beeping when there were clearly no explosives in my bag.

Did I mention that this was after a Defcon in the Las Vegas airport?

I lost what little respect I had in the system (note: Not the people you would ever see on the floor, they have been pretty OK for the most part) at that point.

Between the War On Moisture, pointless shoe removal, and a TSA that can't ever answer any question with the word 'Why' in it, I have absolutely zero faith in the system any more.

I am a frequent flier, put in over 100K miles last year and am on track to do more than that this year. If you simply go through the airports enough, you can trivially avoid any security measure there is, it isn't even a trick.

So, spray on bomb detectors? Great. So? Send the bad guys through security 25 times and you will see several obvious ways to not get it checked. Game over.

          -Charlie

DOS attack

[snsh]

I never understood what happens when an airport baggage handler gets a second job as a landscaper, and comes to work every day covered in nitrates, and spreads it on everyone's luggages? How do chemical detectors deal with all these sources of noise?

Re:how about glycerin

[Atraxen]

You've fallen into the most common problem non-chemists have when reading about chemistry. Glycerin is NOT the same thing as trinitroglycerin. The reactivities aren't even close, and the structures have significant differences which lead to very different behaviors. Another comment also treated household hydrogen peroxide as equivalent to all other peroxides, and assumed they would all be detected the same way (this shows the same misconception, but is accidentally more correct than the parent comment...)

http://en.wikipedia.org/wiki/Glycerin
http://en.wikipedia.org/wiki/Trinitroglycerin

Remember folks, if you're chemically untrained the WHOLE word is what you should be looking for (there is structural info in the name, and that helps give rise to the properties we observe, but interpreting structures into behavior is tricky even for professional chemists....) Some analogous circumstances which arise from noticing a word fragment and extrapolating.....
screw = screwdriver
son = sonogram
hill = hillary
bus = business

I'm sure there are better examples, but hopefully I've made the point.