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

let me guess

[HalifaxRage]

Let me guess.... MacGyver happened to haev a paper clip and a rubber band beside the computer.

It's a well known fact...

[SnoopJeDi]

Viruses can be transmitted via CD.

Don't trust strange CDs.

[/PSA]

Biological samples

[LiquidCoooled]

I'm sure some people have already been using CD drives with biological samples smeared across the disks.

Mental note: never rent porn dvds.

Rooted

[Chyeld]

Sadly, the drive was later mistaken as a normal CD drive and one of the researchers attempted to play the collection of Sony CD's on it. Now the drive refuses to do anything, claiming the pesticides are patented and trademarked and detecting them would be a violation of someone's Intellectual Property.

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:No, not quite.

[jimstapleton]

Yes, but would you be willing to give up eating Cheetos to know the recipie?

Missing the Point

[ivormi]

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."

I think he's missing the initial point here. 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, but by itself, this provides testing capabilities to a much wider set of labs.

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

Why so expensive?

[SQLServerBen]

The real question is, if the laboratory machines are using more or less the same technology as the CD drives, why do the actual lab machines cost so much more? From TFA, the machine this replaces costs 30-60k Euro, compared to 15 Euro for a generic CD drive.

Re:Why so expensive?

[Colin Smith]

Quality...

Re:Why so expensive?

[db32]

The answer is simple. Demand. Lets assume the size of the mfg plants, number of employees, and so on are the same for 2 companies, one making the lab equipment one making generic CD drives. I think it is safe to assume that the lab machine is going to be more expensive on materials alone, but not by the amount in the price difference between a generic CD drive and it.

How many generic CD drives do you think the company can expect to sell vs lab machines. You can find at least 1 if not multiple generic CD drives in a given home, office, etc. You are likely to only find the lab machines in hospitals, and probably only a few if more than 1. If the generic CD drive company expected to sell as many drives as the lab company sells machines the price would be astronomical too.

Re:Why so expensive?

[sholden]

Except that a third party company could buy generic CD drives and convert them. I doubt the conversion process would cost 30k euro, if the people who made this one can do it then it can probably be done with standard equipment possibly mostly by manual human work (if demand it so low).

More likely reasons:

* The lab machine is more accurate and more importantly calibrated and tested to be so.
* The lab machine passed a bunch of standards to be approved for use on something a generic CD drive isn't.
* The lab machine does a bunch of other stuff that the generic CD drive doesn't - using different wavelengths, etc

It could also simply be that no one noticed you could meet a subset of the requirements for the lab machine with a much cheaper design, and hence no one did so. Of course there may be patent issues that mean no one will do so now anyway...

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.

and then...

[JeanBaptiste]

you can hack your DVD drive to destroy the pathogens

explanation

[Iron Corona]

0.02 micrograms per liter

What does this mean exactly? 0.02 micrograms per litre of what?

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.

Re:Not too surprised...

[EricR86]

You may think that's supposed to be a joke, but CD lasers are really dangerous. They're labeled safe (Class I ?) on the CD drive because they're inside a closed space. If you remove it from its enclosure it suddenly becomes a very unsafe device to use, especially when you expose the laser. CD lasers are IR, which means your eyes will not blink, and save you, from your eye focusing a collimated beam on the back of your retina. You would quickly go blind. And all this would take place in a fraction of a second.

Re:The question on everyone's minds...

[Anonymous Coward]

I think you mean paper mâché, not paper machete.

Making a big knife out of paper kinda defeats the purpouse.

Re:explanation plus a bit

[Anonymous Coward]

0.02ug/L of protein is what I got from reading the article.

The array can have 300,000 spots of different proteins.

Each spot is at a fraction of a uL volume. The sample must be at 0.02ug/L to be detected.

This is a huge step over commercial applications for a variety of reasons.

First array density

For example I do nucleic acid microarrays (even though the example in the article is protein arrays). We can look at ~30000 samples per array, so the people in the article are able to assess an order of magnitude more information than the system I use, and half an order of magnitude more information than the really expensive systems (for nucleic acids).

The second is sensitivity.

Typical protein assays are done in 96 well plates in the average lab, drug discovery labs may use 3800+ well plates and get results. The advantage of these assays is that the total protein amounts will be on average much higher than in the 300,000 sub uL volume spots printed on the CD that have to be 0.02ug/L or better. So the detection apparatus is actually quite good in the case of the CD detection system.

Third is cost.

The high end nucleic acid systems which are half an order of magnitude worse for sample density cost about 250,000$ for initial equipment costs. Plus more for analysis. The cheaper system that I use ends up using the EXACT same software package they used for downstream processing. CD's are cheaper than custom glass slides.

Fourth is procedural.

A little further customization of the system to make it somewhat fluid tolerant would allow for the drive to also act as a dryer which is achieved currently on glass arrays by buying a special centrifuge. The CD player is the centrifuge.

The REAL question...

[SplatMan_DK]

Actually, the REAL question is...

WILL IT BLEND?

;-)

- Jesper