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."

OH NO!

[elmegil]

GERMS!!! [tvtome.com]

China?

[allden]

Is University of Florida in China?

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 [ocpaweb.org] So, as you can see, the problem with a melting pot is that some bits refuse to melt.

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

[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.

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.)

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

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 w

Hilarity ensues.

[NotoriousQ]

I think you posted to the wrong website. You should be posting here [fark.com].

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!

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 justi

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 [wikipedia.org]). (This also happens with fused aromatic rings, found in most useful fluorescent dyes, including the ones that Tan's grou

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.