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

Wonder if this is related to Discode?

[ahfoo]

Discode was a project to do an "open source" bio hardware device that sounds very similar to this. The project was going on under the guidance of a UCSD professor and got a lot of write up about three years ago but it seemed to slowly disappear over the years.

No, not quite.

[Applekid]

From TFA:

However, Corran believes that the Spanish team's procedure needs to be developed further. "They still do part of the assay in a normal plate. Until the whole thing can be done on a CD it doesn't have a great technical advantage." Meaning there is no Hacked CD Drive Biochemical Scanner, there's a Hacked CD Drive component to a Biochemical Scanning System.

I'd be willing to give up my last 5.25" bay if I could use it to give me the secret cheeto powder recipe.

Re:Missing the Point

[kebes]

The point is to reduce the overall cost of being capable of running the test, not in vastly increasing the efficiency of running a massive batch of tests this way. Certainly there's downstream potential for it...

Actually there is already research being done in that regard. Some research groups are experimenting with building microfluidic systems on compact-disks. The spinning of the disk generates a centrifugal force that acts as the 'pump' for the device, driving fluid through stages. You can even have special valves in your device, and by changing the rotation speed of the drive, you progressively move the fluid from stage to stage.

Then the CD laser can be used as a detection mechanism at different locations along the disk. Also you can obviously run multiple experiments at once, since as the disk spins the laser passes from one fluid channel to the next.

It's a rather cool idea to use commodity CD-drives for these high-tech assays. I'm not aware of a good review of these experiments, but here are two papers on this subject:
Siyi Lai, Shengnian Wang, Jun Luo, L. James Lee, Shang-Tian Yang, and Marc J. Madou "Design of a Compact Disk-like Microfluidic Platform for Enzyme-Linked Immunosorbent Assay" Analytical Chemistry, 76 (7), 1832 -1837, 2004. doi 10.1021/ac0348322

Horacio Kido, Miodrag Micic, David Smith, Jim Zoval, Jim Norton and Marc Madou "A novel, compact disk-like centrifugal microfluidics system for cell lysis and sample homogenization" Colloids and Surfaces B: Biointerfaces Volume 58, Issue 1, 1 July 2007, Pages 44-51 doi: doi:10.1016/j.colsurfb.2007.03.015

Re:explanation

[James McP]

It isn't meaningless, but it is a context-less number. Let's try this a different way.

Bob the scientist goes and gets samples from the air, soil, water, and fish at a site. His sensor can go down to 0.02 micrograms of pesticide per liter of sample. When he checks the results he finds the sensor found no pesticide in the air, 0.05 micrograms/L of pesticide in the soil, 0.02 ugrams/L in the water, and 0.15 ugrams/L in the fish.

The context provides the useful part of the data. The soil shows significant levels of pesticide, indicating it was the area directly sprayed. The air sample shows no pesticide to the limit of the sensor so the spraying was done more than a few hours ago. The water is somewhat contaminated but also at the limit of the sensor so it probably isn't that bad as long as there is rain to further dilute the compound. However the fish sample is several times higher than the water or soil sample, implying the pesticide has been used repeatedly and that the ecosystem may start suffering damage.

If the sensor was limited to detecting 10 micograms/L then you couldn't detect the pesticide prior to visible symptoms in the wildlife. By having a more sensitive sensor you have greater lead time to finding problems. For forensic-type activities, it also means it is easier to track down the point source of the pollutant.