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Universal Surface Scanner Detected
mcgrew writes to tell us that scientists at the University of California, San Diego, have created a new system that can test any surface for just about anything. "Their idea uses a thin layer of metal drilled with nanoscale holes, laid onto the surface being tested. When the perforated plate is zapped with laser light, the surface plasmons that form emit light with a frequency related to the materials touching the plate. A sensitive light detector is needed to measure the frequency of light given off. The team says devices using this approach can be small and portable, will work on very low power, and could detect everything from explosives to bacteria. All that needs to be done now is build a system able to decode the light signatures."
Would this type of detector be able to differentiate between species of bacteria?
And the optical sensor, while being non-trivial, doens't just sense magically everything from explosives to bacteria. You have to chemically engineer receptors . That's also very non-trivial.
if it's just down to detecting the frequency of the light emitted, couldn't some sort of photovoltaic or photoelectric sensor be designed so that you wouldn't have to chemically engineer receptors for different kinds of surfaces, but rather just program the software to identify the surface material?
Surface Plasmon based sensing has been around for a long long time. From what I've read, it doesn't seem that this method/technique is anything revolutionary, nor is it ever going to magically determine what bacteria/explosives are on a surface. As someone mentioned in a previous post, you need to chemically engineer probe molecules for any bio-target that you are trying to specifically detect. All the device is going to tell you is that you have some shift in frequency due to some sort of binding/contamination on the surface of the material you are probing (as compared to a pristine surface).
However, in most cases it cannot give you any more information about the actual material/molecules that are causing this frequency shift. Usually SPR based sensors are sensitive to refractive index variations at the surface of the metal surface (where the plasmons oscillate) much like most optical sensor technologies. While these technologies can all tell you if you have some binding/contamination on a surface due to "stuff getting on", they can't really identify this material unless coupled with some other identification techniques or by modifying the surface to make sure that whatever binds is infact specific to the surface.
Maybe now we will be able to determine what can be found McDonald's hamburger patty.
You laugh, but what I'd like to do with such a thing ain't so far off the mark from that...
Basically, my wife has Celiac disease - if she eats food that has wheat flour or bread crumbs in it (even in very small quantities) it makes her sick. Long-term consequences from repeated poisonings include a higher risk of intestinal cancer...
So the problem is, eating out, it's often hard to know what's safe to eat. If I could get some kind of scanner that could detect gluten in food... that would be awesome.
Of course, from the way this thing works it sounds like the gluten would have to be somewhere near the surface of the food... So I guess it's way too early to get excited...
Bow-ties are cool.