Desktop Biodetectors

IvyMike writes: "EE Times has an interesting article on the development of desktop biodetectors that could quickly detect the presence of pathogens like anthrax and smallpox. It uses some pretty cool technology to identify the target pathogen's DNA. Too bad we don't have these things today."

Comments

Can they make one for my refridgerator?

[fobbman]

I've got some leftovers in there that are really borderline.

Parameters

[Halloween Jack]

Considering what some people do at their desks, with the door closed... better not set the biodetection parameters on the desktop units too wide.

"Sir, the bioalarm just went off in the boss' office! We need to get a hazmat team up there right away!"

"Relax, rookie. Look at the DNA profile. Those are gametes. Billions of 'em. Nothing a few paper towels can't clean up."

"But, sir... they don't match the boss' DNA."

"...well, whaddaya know. Looks like we have a big raise coming, rookie."

Too bad we don't have these things today?

[Phrogz]

OK, sure, they're cool gadgets, but saying that is like saying "Too bad we don't have gadgets on the desktop to detect incoming meteors."

What are there now, somthing like under 30 cases of Anthrax so far? Sent to a few high-profile companies? Sure, that's a MASSIVE INCREASE over previous levels, but statistically you're still in pretty good shape. Don't let the media hype get you worked up.

Too bad we don't have detectors on our faucets just in case the level of mercury rises rapidly...

Re:Too bad we don't have these things today?

[sam_handelman]

What are there now, somthing like under 30 cases of Anthrax so far? Sent to a few high-profile companies? Sure, that's a MASSIVE INCREASE over previous levels, but statistically you're still in pretty good shape. Don't let the media hype get you worked up.

Very true. Also one of the (many) reasons why these things won't work. I'll stick with the three simplest.

Firstly, in order to detect bacterial DNA you have to lyse (break open) the bacteria. This means you have to filter them out of the air, dissolve them in lysing buffer and apply them to your detector, at the bare minimum. Lysis buffer is expensive, and I doubt there technology actually works without doing more than lyse the cells (removing the cellular protein, much of which binds indiscriminately to DNA, would be a good start. Doing that in reasonable time requires a ~12,000 RPM centrifuge, precipitant compounds and a column, at the minimum.)

Secondly, DNA from other organisms is going to bind to your probe (including these gold bead things) with a certain frequency (this binding is called "base pairing," which is largely driven by hydrogen bonding but is not called a bond.) So, your background noise from that is going to be more than enough to drown out the signal from an anthrax concentration high enough to kill you, especially if you're standing across the room from the detector holding an envelope; the anthrax concentration drops as the square of the distance from the contaminant source unless there's a wind.

Thirdly, the reason the previous poster mentioned. In order for these things to be useful the false positive rate has to be on the same order of magnitude, or smaller, than the actual positive rate. Even if you use practical techniques instead of this absurdity with DNA, that's never going to happen. More practical techniques depend on markers on the bacterial cell walls (so you don't need to lyse the bacteria); when the CDC people report "preliminary results" indicating anthrax this is what they're talking about - these results are preliminary because there are many other, more common and harmless bacteria that have the same factors in their cell walls, and because the experiment to detect the stuff occasionally goes wrong for no apparent reason.

Even in a laboratory setting, if you want to detect the DNA from this stuff you have to *culture* it. The idea of a desktop machine, as opposed to a highly trained scientist with a lab full of sophisticated equipment, being able to detect the DNA from the amount of this stuff that is actually floating in the air is patently and absolutely absurd.

A handheld is even more so, since it wouldn't even be able to dissolve the bacteria it filtered.

These devices are either a pipe dream, a scam, or both. Either they'll just report A-OK all the time or, even worse, they'll periodically start an unjustified anthrax scare by giving off an alarm.

Re:Too bad we don't have these things today?

[dgroskind]

statistically you're still in pretty good shape

But potentially we're in very bad shape.

The day after the attack on Pearl Harbor, people on the mainland were as statistically safe as they were the day before. The difference was the country was at war and many more casualties were certain.

What the anthrax statistics mean is that people have biological agents and are willing to use them. There no reason to think they will stop with anthrax. The threat will continue for many years.

There's some hope that this attack will be limited because of the crudeness of the delivery mechanism and the fact that anthrax wasn't engineered to resist antibiotics. There even a faint hope that this attack isn't part of the events of 9/11.

However, no other terrorist organization has ever stopped with one attack. If bioterrorism is part of their arsenal, we can expect the terrorists to use it again the way the IRA continues to plant bombs.

It's reasonable to expect devices like the one in this article to become as common as smoke detectors.

Open Source only, I'd wager.

[Soko]

So, you think Windows will be able to detect a virus? Riiiiiiggghttt....

Soko

Ridiculous...

[ryanwright]

What a ridiculous idea. What with people stocking up on gas masks these days, we don't need them clamoring for "desktop biodetectors" that will never prove useful for more than 0.0001% of the population. Way to add to the paranoia, /.

Economist Article

[cosyne]

The economist is running an article about a anthrax detector at http://www.economist.com/science/displayStory.cfm? Story_ID=821937.

"A better solution would be to screen on the spot. And technology to do this is now available. It uses a test strip, costing $20, that looks like a pregnancy-detection kit."

May be useful it you (or your employer) regularly do(es) things to piss people off so much that they'd want to kill you....

Employee Survelliance?

[oliverk]

Can you see the reports to management?

EMPLOYEE: JONES, PAUL
Biohazards: Clean
Infectious Diseases: Clean
Genetic anomolies: Clean
Pharmacopia: Found -
** ASPIRIN - Trace Amounts

==================

Report submitted to Human Resources for individual factors improvements...

These reports, while "sold" as providing the ability to detect hazardous materials could in fact be used in a manner similar to the Gattica theory: testing for genetic predispositions or even medications (say, the AIDS cocktail) to determine whether you should get that promotion or not. Really, from the business end--you've got rounds of layoffs, shouldn't you have the best information when selecting who goes and who stays?

:|

Best thing about such a device

[namespan]

The best thing about such a device is that it could justify its cost.

A $500 "detect Anthrax" device wouldn't yield much value for a large portion of the population. But... a $500 device that could detect and identify a wide variety of microorganisms might be very useful -- and worthwhile -- indeed.

Maybe it'd be like running "top" -- instead of giving you information about processes taking up system resources, you could get information about microorganism activity in the environment (or your body, given an appropriate sample...).

ID NAME EST COUNT/CU CENT % OF TOTAL
787 Staphlo 2324572 12.2%
8901 Antrax 253334 1.3%
143 E. Coli 289217 1.4%
1589 Ebola 16333 .035%

desktop not what you think it means

[myc]

The term "desktop" as used in the eetimes article probably does not mean what your typical computer geek thinks it means, as evidenced by the many posts so far. It's not a consumer device that sits on top of an home/office desk of the overly paranoid. Rather, it probably means that the device is sufficiently bulky as to make it not portable, and therefore must sit on a workbench in a lab. While such a device is useful for testing labs, its utility is somewhat less because it can't be used in the field.

That said, this is really cool technology. It's potentially much faster than the standard tests today, either polymerase chain reaction (PCR) or spore cultures (which is the *only* way to 100% reliably test for anthrax but is also the most time consuming protocol). Aside from testing for microbial agents, it sounds like the technology may have applications in high-throughput gene analysis.

Re:desktop not what you think it means

[myc]

FYI I do work with DNA, I am a postdoc at Harvard Med School. The fact of the matter is, antibodies are a bitch to work with. Unless you make a hybridoma you can't mass produce antibodies, and even if you do have a good antibody the best you can do is an ELISA assay. There is no way that ELISA is more sensitive than PCR. This bead technology is likely to be more sensitive than PCR, faster than PCR, or both. It's also not that hard to extract DNA, usually a simple organic extraction gives you a good enough sample to work with.