New Nanotech Foodborne Pathogen Detection

CodeWanker writes "Scientific American is reporting that scientists in China have developed a better, faster way to screen foodstuffs for infectious agent contamination. Bind antibodies to flourescent silica bits, mix with your hamburger, and turn on the black lights. Hilarity ensues."

Comments

OH NO!

[elmegil]

GERMS!!!

The real test..

[cybrchrst]

The real question is whether the Chinese could have done anything about Tyler Durden being involved in a class action lawsuit against the Pressman Hotel regarding the urine content of their soup.

China?

[allden]

Is University of Florida in China?

Re:China?

[Anonymous Coward]

Is University of Florida in China?

Well, the new trend *is* towards outsourcing ...

Re:China?

[Anonymous Coward]

Nope, but the researcher has a Chinese name, and it would be too much for the submitter to read the whole article, when sweeping statements are so much easier. Besides, it is far more interesting (and thus more likely to be posted) when "scientists in China" do something, rather than researches at the University of Florida...

Re:China?

[CodeWanker]

Actually, I said "In China" because of the awesome allegiance Chinese scientists often pay to their mother country when here. The Chinese got MIRV nuclear missile tech from a Chinese scientist working at Los Alamos and smuggling data to the ChiComs. It's gotten so bad, Chinese scientists have had to set up apoogist/propoganda sites So, as you can see, the problem with a melting pot is that some bits refuse to melt.

Re:China?

[Anonymous Coward]

I have to second that, unfortunately. Whether or not Wen Ho Lee was actually a Chicom stooge, one investigator's anti-Chinese paranoia seems to be more than matched in response by a wave of seige-mentality paranoia on the part of the Chinese community.

Self-serving mis-attributions are probably a commone syndrome throughout the human race. For example consider how many things are called American ingenuity in the American memespace, when in fact they were also independently invented in numerous other places.

For another example, when Kodak sued Sun for something about Java, Chinese friends told me a Chinese company was suing Sun for IP Sun had stolen from China. How they misconstrued Kodak as a Chinese company, I will never know. Chalk it up to racist brain-fart static.

Americans or Europeans etc don't have a monopoly on that kind of racism/ trash talk by any means, but it can be informative to listen to other people's crap propaganda like that and marvel at the fact that you sound just as stupid to them as they do to you.

Nice

[Anonymous Coward]

New and improved mesothelioma, now with Listeria.

Health and Safety

[reyalsnogard]

Okay, so it is now physically possible to detect E.coli -- the leading cause of food poisoning -- accurately and in under twenty minutes, but

• how

will this retard mishandled food during preparation? (e.g. chefs who don't wash their hands) Shall happy meals now come w/ crank-powered blacklights?

Re:Health and Safety

[Anonymous Coward]

Simple! I will look like a retard with the blacklight I will carry with me everywhere I go--along with my supply silica antibodies or whatever. It is powered by the adult happy meal mcdonalds pedometer.

Re:Health and Safety

[Anonymous Coward]

New /. annoyance: emphasizing words just like you did.

Re:Health and Safety

[eingram]

Well, if food keeps coming up contaminated, we know who to blame (those crazy chefs)!

Maybe fear of losing their job will improve the preparation process?

Allergies...!?

[CompSurfer]

I wonder if this could be applied to use as an allergen detector for people with food allergies. As a person with peanut and nut allergies, it would be quite handy.

Re:Allergies...!?

[Anonymous Coward]

No, it can't. Allergy is your body's immune system flipping out over a protein it can't assimilate. This technique specifically uses antibodies, which bind to and interact with bacteria (generally not related to allergy).

Aside from the difficulty of detecting the specific allergenic proteins, there would probably be a difficulty in quantity. Peanut slivers don't reproduce.

(My sympathies with allergy - I'm mold and dust mite allergic, and it is pure hell some days/nights.)

Re:Allergies...!?

[Anonymous Coward]

Heheh. Having read TFA, it appears that the technique can find a single bacterium. Impressive, but I have trouble believing that that performance will easily carry over if/when this is put into practice.

Field testing

[Muhammar]

1)Very useful. I think simple test kits can be made - much like the pregnancy test strips - for consumers to check all kinds of stuff. ("Test your partner within 20 minutes")
Or at least for the grocery/fast food stores to use on the stuff they are selling.
2)Fluorescence, not flourescence. (Americans also cannot spel aluminium.)

Re:Field testing

[Billy the Mountain]

Very useful. I think simple test kits can be made - much like the pregnancy test strips - for consumers to check all kinds of stuff. ("Test your partner within 20 minutes")

Except for one detail. Some contaminents can be harmful in small amounts and may be invisible to the unaided eye even when tagged. As I recall from a stint working in public health, people can easily get sick when food is contaminated with a very few organisms of E. Coli 0157:H7, So those test strips should, at the very least, come with a really high powered Cap'n Crunch magnifying lens.

BTM

Hilarity ensues.

[NotoriousQ]

I think you posted to the wrong website. You should be posting here.

Here, on slashdot we like news for nerds, without any hilarity ensuing. Thanks.

Re:Hilarity ensues.

[Fortran IV]

Yes, here it would be: "60-nanometer granularity ensues."

D-oh! That's so obvious...

[FFFish]

...that I wish I'd thought of it.

Fast Food Fun

[wirwzd]

1. Use on friends half eaten hamburger.
2. Turn on blacklights.
3. Vomit!

American English...

[Teechur007]

...was devised by Merriam Webster as an attempt to break away from "the King's English" as it was called. Americans started "misspelling" words on purpose (colour --> color), as well as changing some British words entirely, in order to seem more separate from the motherland.

So you can take your "misspellings," and shove 'em in your "loo." :P

--Teechur007

Now my order at Burger King

[Fortran IV]

can take 20 minutes longer. Great.

What about unsaturated fats?

[zymurgy_cat]

Don't all double carbon bonds fluoresce when exposed to blacklight? I've used this to test cleanliness in industrial applications where a customer was applying an stamping oil and then cleaning the part afterwards. I'm curious as to how you'd turn this into a quick consumer test without making people freak over unsaturated fats naturally present.

Any experts out there care to weigh in?

Re:What about unsaturated fats?

[mistersooreams]

I'm not the expert (come on, this is Slashdot!) but you do make a good point in general. Any test like this might seem or even be 100% accurate in the lab, but once you talk about using it in the real world, you have to be very careful. However simple this test might be to conduct, real people make real mistakes.

What if this test gave a false positive for E. coli in a Happy Meal? You'd have a screaming mother, a screaming child, and a test approved by that magical flawless black box called SCIENCE to justify their screaming. That's not to say that the average mother is an idiot for trusting science, but I do think that we should be careful when exposing ordinary people to complex things like bacterial testing.

Needless to say, the legal situation from a false negative could be even nastier.

Re:What about unsaturated fats?

[Anonymous Coward]

Type I and Type II error, baby! Forget calculus, basic statistics (and I don't mean that mean, median and mode bullshit) should be required in school. Infinitely more useful in making everyday decisions than being able to figure out the area under a parabola. (Unless you are an engineer, then you should know both.)

Re:What about unsaturated fats?

[amide_one]

The excitation wavelength/absorption spectrum for unsaturated organics depends on the number of consecutive double bonds. Single double bonds (ones by themselves, instead of long chains of double bonds) absorb starting around 210 nm - vacuum UV, with no visible emission to speak of at all. Long chains of double bonds shift the emission up to higher wavelengths (a result of conjguation). (This also happens with fused aromatic rings, found in most useful fluorescent dyes, including the ones that Tan's group uses.)

In ground beef, presumably the unsaturated fats that might interfere would be fairly evenly dispersed, giving a uniform low background fluorescence that's pretty easy to filter out and ignore, either during collection or after. The labeled antibodies show up as very bright spots, like in the pictures in the article. (In raw samples, the fat would be concentrated into fatty spots that can also be ignored by only looking at "meat" regions instead of "fat" bits.) It worked well for the stamping oil because, when there's not supposed to be any fluorescence in a part, it's very easy to see the glow of oily residues.

I'm not sure that this is really intended as a "quick consumer test" at the restaurant level (there'd have to be a LOT of E. coli on the burger before the whole surface glows), but it's much better than having to do amplification (PCR) before checking for E. coli DNA.

I submitted this to FARK...

[biolabrat]

...with a better headline!

E coli, yeah... but which one?

[igollum]

Below is the full reference and abstract of the research paper in question, which I feel is much more interesting and informative than the three and a half words in the Science article, which fails to make some very important points - like the fact that it's not just any E. coli they're after, which are all over the place anyway, but mainly type O157:H7, which is the big nasty. There is a huge genetic diversity in the species, the name being more an umbrella term than anything - there is more genetic difference between two average E. coli subspecies than between close cousins Bacillus thuringiensis (biopesticide sprayed on crops) and Bacillus anthracis (responsible for anthrax). My point is, being able to quickly detect the bacteria in general is nice, but hardly new; the real challenge is to specifically detect the baddies, which is much tougher.
Addendum: I've just finished skimming through the PNAS paper and apparently the selectivity of this method is pretty good, which should minimize food-scare inducing false positives. More good news is they're also adapting it for other food contaminant like Salmonella (eggs, poultry etc) and Bacillus cereus (pasta, rice etc). Finally, after reading the Materials & Methods section, I can confirm that the plan is definitely not to illuminate burgers with blacklight - the method involves several sample preparation steps to bind the fluorescent particles and so on, and the reading is taken using a spectrophotometer set to specific excitation and emission wavelengths, solving the problem mentioned in another post of background signal due to fat and whatnot.

From the Cover: A rapid bioassay for single bacterial cell quantitation using bioconjugated nanoparticles. Zhao X, Hilliard LR, Mechery SJ, Wang Y, Bagwe RP, Jin S, Tan W. Center for Research at the Bio/Nano Interface, Department of Chemistry, and The Shands Cancer Center, University of Florida, Gainesville, FL 32611. The rapid and sensitive determination of pathogenic bacteria is extremely important in biotechnology, medical diagnosis, and the current fight against bioterrorism. Current methods either lack ultrasensitivity or take a long time for analysis. Here, we report a bioconjugated nanoparticle-based bioassay for in situ pathogen quantification down to single bacterium within 20 min. The bioconjugated nanoparticle provides an extremely high fluorescent signal for bioanalysis and can be easily incorporated with biorecognition molecules, such as antibody. The antibody-conjugated nanoparticles can readily and specifically identify a variety of bacterium, such as Escherichia coli O157:H7, through antibody-antigen interaction and recognition. The single-bacterium-detection capability within 20 min has been confirmed by the plate-counting method and realized by using two independent optical techniques. The two detection methods correlated extremely well. Furthermore, we were able to detect multiple bacterial samples with high throughput by using a 384-well microplate format. To show the usefulness of this assay, we have accurately detected 1-400 E. coli O157 bacterial cells in spiked ground beef samples. Our results demonstrate the potential for a broad application of bioconjugated nanoparticles in practical biotechnological and medical applications in various biodetection systems. The ultimate power of integrating bionanotechnology into complex biological systems will emerge as a revolutionary tool for ultrasensitive detection of disease markers and infectious agents.

Re:Spelling

[Anonymous Coward]

"Americans also cannot spel aluminium."

That's because we don't pronounce it 'al-loo-min-ee-um', but rather 'al-loo-min-um' - it's a different word.

Speaking of spelling, where is the 'f' in lieutenant, pronounced by many Brits as 'leftenant'?