CPU's Heat Output to Amplify DNA Could Make Drastically Cheaper Tests

MTorrice (2611475) writes "Researchers have harnessed that heat from a computer CPU to run the polymerase chain reaction (PCR) to amplify DNA in a blood sample. The team developed software that cycles the temperature of the CPU to drive PCR's three distinct steps.The method allowed them to detect miniscule amounts of DNA from a pathogenic parasite that causes Chagas disease. They hope their technique will lead to low-cost diagnostic tests in developing countries." (Always good to put waste heat to a practical purpose.)

Comments

You completely missed the point of the article

[Anonymous Coward]

The big deal is they could do this with the existing machine, and they didn't need to make modifications.

Waste heat has nothing to do with it.

Re:You completely missed the point of the article

[thesupraman]

No, it is a stupid article. Someone has come up with an over-complex solution to a non existent problem.

The use of the CPU to create temperature is a overly complex and difficult approach, compared to using a simple regulated heater which would be much simpler, more reliable, more repeatable, and cost less.
Really, they are using a whole computer just to generate the heat, and a separate computer (cellphone) to run the reaction. stupid and overly complex.
If there is a demand for a usb controlled accurate heat generator it would be trivial to build one with a usb microcontroller, its pwm output, and a heating resistor.
it would cost less, be more accurate, smaller, waste less power, more reliable, cheaper. I doubt it would be difficult to find a suitable device already from some
similar application.

Temperature regulation is absolutely NOT a contributing factor to high cost of such tests.

Hell, a power supply, some switches, and some resistors would do it if you didnt want automatic control.

Reminds me of

[UnderCoverPenguin]

This reminds me of a CPU fan that is powered by the heat using a tiny Sterling Engine. Maybe not the kind of "practical use" of the waste heat the editor had in mind, but still an interesting idea.

Seems like overkill

[Rich0]

Do you really want to stick a whole PC in a lab, expose it to chemicals, and put its CPU through repeated heat/cool cycles just to save on a thermocycler?

They mention costs like $19k to obtain one otherwise. I'm sure they sell for that much just as I'm sure you can go spend $2000 on a linux license, but all a thermocycler needs to do is heat samples and cool them. Clearly the CPU isn't going to be a high-performance cycler - you could probably build a little cycler that just uses radiative cooling and some resistive heating for $50. I see peltier heat sinks selling for $40 these days, so I'm sure for $100 you could build a thermocycler on the cheap.

An ideal thermocycler just needs to heat samples to about 95C for a few seconds, cool them down to about room temperature for a few seconds, and then hold them at something around body temperature for a minute or two, The time spent ramping temperature up/down is basically dead time, and you have to repeat this 20-30 times, so if your cycler can change temperature in seconds instead of minutes you can save a LOT of time per test. Peltier effect tends to be the way things are done, or at least it was back when I was using these in the labs.

It looks like openpcr.org has a unit for $600. I'm sure it could be improved on, but I imagine that as you get cheaper, you lose precision, and that does matter. I can't imagine that a CPU can maintain a temperature +/- 0.5C without quite a bit of effort.

Obligatory XKCD

[gerf]

Obviously they use the spacebar to toggle the heat on and off. https://xkcd.com/1172/

Re:Actual Link And Better Details

[UnderCoverPenguin]

The takeaway is that PCR equipment sounds far more expensive than it needs to be.

A lot of equipment is more expensive than it could be. Doing more than a cosmetic redesign opens up a vendor to liability issues. Until either the lawyers are comfortable that the cost savings of a new design sufficiently outweigh the potential cost of law suits or they see competitor stealing too much of their business, they won't be willing to take the risk. Right now, these third world countries don't look like good enough markets to bother with.