DIY Biochemical Scanner From a Hacked CD Drive

holy_calamity writes "Turns out hacking two extra light sensors into a CD drive can turn it into a lab scanner to read the results of high-accuracy immunoassays used to detect disease markers or pathogens, New Scientist reports. The drive proved able to detect pesticides at concentrations as low as 0.02 micrograms per liter."

Comments

Re:Why so expensive?

[eli pabst]

Quality...

Having actually worked with laboratory equipment, that should be modded funny.

Re:Why so expensive?

[blincoln]

I imagine buying those drives for parts is probably more expensive than paying for the components they actually need out of those drives fresh and not having to convert things.

Actually, this is almost certainly not the case. Economies of scale have given us dirt cheap CD-ROM drives. You can buy several models - brand new - at e.g. New Egg for about US$12. You would probably pay about that much for just the status LED, open/close button, and motors at e.g. Frys. This project benefits additionally from the mechanism as a whole - they get the controller firmware, the mechanical bits and bobs related to holding and spinning a CD, most of the device/PC interface, etc.
My dad is a mechanical engineer, and when I was a kid he once remarked on a similar subject - he had replaced his broken car stereo, and out of curiousity disassembled the old one. Inside he found a tiny planetary gear assembly, which would have been more expensive than the entire factory stereo if purchased as an individual component instead of mass-produced for Honda.