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."

Comments

How it works

[marcansoft]

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.

Bullshit

[toppavak]

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.

Re:star trek isn't dead yet

[Spiked_Three]

"Now, if Bill G were really interested in changing the world's health... perhaps he'd get on-board with this obvious idea. Who knows. He's got a lot of money."

For some reason, I was bored and just happen to watch the PowerPoint presentation on this thing last week on TV from Washington University. It was quite an impressive device, with many possibilities for multiple uses as part of the design criteria.
 
And the Bill & Melinda Gates foundation was a huge contributor.