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Scientists Hack Cellphone To Detect Diseases
Dave Bullock (eecue) plugs his piece up at Wired on a cellphone modded into a portable blood tester. This could become a significant piece of medical technology. "A new MacGyver-esque cellphone hack could bring cheap, on-the-spot disease detection to even the most remote villages on the planet. Using only an LED, plastic light filter, and some wires, scientists at UCLA have modded a cellphone into a portable blood tester capable of detecting HIV, malaria, and other illnesses. Blood tests today require either refrigerator-sized machines that cost hundreds of thousands of dollars or a trained technician who manually identifies and counts cells under a microscope. These systems are slow, expensive and require dedicated labs to function. And soon they could be a thing of the past."
And thus the building blocks of the medical tricorder are laid.
tack on a portal ultrasound, xray , and micro MRI and maybe doctors bills will start to come down.
i thought once I was found, but it was only a dream.
If anyone is wondering how exactly this works, or wants to build their own, they might want to check out this Weekend Project
Basically, if you've got a (near-)point source of light, and transmit it through the sample, there is only one path of light from the light, through a point in the sample, to a pixel on the sensor, so you don't need a lens. The farther away you place the sample and the closer you place the light source, the larger the image appears (but then you also need to progressively use a better, closer to a true point source light).
I imagine this could work very well with a naked silicon laser diode, since they appear as damn tiny, near point sources of light.
Posted by: jamesdionne:
I agree.
"In prison you just have to shut your eyes and take it. Here you have to shut your eyes and give it."
Well, it's not like those countries are literally in the Stone Age. They're dirt-poor by Western standards, but they have access to some modern technology and can scrape together the money for relatively cheap stuff. (Unfortunately this includes Kalashnikovs.) As the West continues to develop cutting-edge technology, the standard for what kind of things the world's poor can afford rises. That is, nobody at all had LEDs until the 20th century.
Inventions like this raise the level of technology available to most of the world, and do more good for more people than (say) yet another model of iPod. One of the main things I've learned from studying history is that the maximum level of technology in a society is less important than the level that the masses have. Making things cheaper is one of the main ways in which technology has advanced; eg. iron is actually inferior to bronze in several ways, but is cheaper.
In fact, in some ways poor countries have had an opportunity to leapfrog the West. If your country has never had a copper-wire phone system, and you're just getting started with phones, you may as well start off with cell phones or fiber optics.
Revive the Constitution.
A. It can't detect HIV. No imaging technology short of electron microscopy can directly detect the virus itself and even electron microscope would be a retarded way to attempt diagnostics.
Even the original paper describing this technology showed that they have no sub-cellular resolution and even their size resolution was extremely unreliable for anything smaller than 15 microns... which all interesting human cells are (even if you could tell what size cells are you've accomplished.... nothing).
If they are suggesting they can do CD4+ T-lymphocyte counts they're either idiots, ignorant or both. There is no morphological distinction between a CD4+ and a CD4- T-lymphocyte. Even using fluorescence imaging (which they aren't) you have to be able to look at two colors of fluorescence (CD3 label to check to see if its a lymphocyte and a CD4 label to see if its CD4+) immunofluorescence is way too weak to be detected by a cell phone camera, especially a color sensor with 2 micron pixels. The CD4 antigen is never expressed at levels greater than approximately 50,000 / cell, the detection limit of a 5 micron pixel monochrome sensor (the bayer mask makes you lose about 30% of your light) is close to about 150,000 molecules. The bayer mask also makes your sensor pretty much useless for analytical applications, you're screwed if your green-fluorescent cell is centered over a red or blue-sensitive pixel which would happen in, oh, 66% of your pixels.
You run into almost identical sets of problems with every other so-called "application" of this "technology" so, yeah, bullshit.
IAABME.
"UCLA researcher Dr. Aydogan Ozcan images thousands of blood cells instantly by placing them on an off-the-shelf camera sensor and lighting them with a filtered-light source (coherent light, for you science buffs)."
So instead of Occam's Razor, this is Ozcan's RAZR?
When it test's a patient positive for HIV, it plays a polyphonic ringtone of 'Always looks on the bright side of life'
What if Tetris was invented by Nazis?
I can see this possibly evolving into something that would be able to detect malaria infections, malaria is pretty big and easy enough to spot with good magnification and a little bit of training. Parasite laden blood cells are often chock-full of little plasmodium, so they would definitely have different optical properties in this kind of system. This could also probably do a reliable job of some basic blood values like hemoglobin levels, where the item in question has strong, distinct light-absorbing properties, but it won't come close to replacing an actual lab: there are too many things that just don't interact enough or interact distinctly enough with light to be measured that way, even if you had a lab-quality variable-frequency light source.
HIV, however, is a virus, and can not currently be detected or diagnosed microscopically (barring electron microscopes), so I'm a bit skeptical on that point. Besides, we have antibody tests that are cheap, effective and (thanks to foreign aid) available even in the poorest, most remote areas. The problem with testing for HIV is not detecting it, it's getting people tested. There is still a HUGE stigma around it, and people are (often with good reason) worried about the privacy of tests. If this guy has figured out how to detect and, more importantly, identify viruses using light microscopy, he'll be up for a Nobel prize, but I highly doubt that is the case. It's more likely that Wired just embellished the story a bit, which I think is unnecessary since even being able to quickly and reliably detect just parasites in the blood like malaria, leishmaniasis or trypanosomes would be a big help for many in the developing world.
I spent 2 years living in remote, rural Tanzania and some of the clinics near me diagnose malaria in every blood smear they see, because they don't have someone well trained enough to examine the blood, or they don't actually have a functioning microscope (they are freaking expensive, very fragile and hard to get out in the boonies) so they err on the side of caution. Even though they are probably correct a good percentage of the time, people were often "diagnosed" with malaria when they had none of the symptoms: Malaria gets the blame for nearly every ailment. This leads to overuse of anti-malarial drugs, which leads to drug-resistance. I also saw anemia being diagnosed very frequently as well, with out any way to properly test for it. It was the second most popular target for any ailment. "Anemic" people are encouraged to eat a substance made from red clay. It probably has plenty iron so it could actually help and probably can't do any harm, but it tasted about like you would expect dirt to taste.
To make my point: if this all this could do was detect malaria and hemoglobin levels, at even 10x the cost of a cell phone, but as portable and as durable as a cell phone (relative to a microscope that won't survive a car ride), it would make a sizable impact for a lot of people.
"Cheeze it!" - Bender