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'Lab On a Chip' Made From Paper and Tape
An anonymous reader writes "Researchers at Harvard University have developed a microfluidic device using ordinary paper and tape. Squares of paper are layered and connected with adhesive tape, channeling liquid horizontally and vertically in a very small area. Each square of paper has been treated with photoresist material, which creates channels that funnel liquid into tiny wells containing certain proteins or antibodies. The fluid interacts with that area of the paper and turns the well a certain color. It can, for example, detect varying concentrations of glucose. Lead researcher George Whitesides says such paper 'lab on a chip' tests may lead to a cost-effective, portable, and accurate method for diagnosing diseases in countries lacking reliable health care. The research appears in the current issue of the Proceedings of the National Academies of Science."
... microfluidic Shrinky-dinks! All you need is a laser printer, shrinky dinks, and a toaster oven. :-)
There's no place I can be, since I found Serenity.
Ok, so they taped a bunch of test strips together. Does that really warrant the 'lab on a [micro]chip' title? I mean, it's a (somewhat) great (if not new) idea to tape a bunch of different test strips together to consolidate tests onto one device, but is it a reusable microchip like they are attempting with the current of 'lab on a microchip' projects?
Don't hold your breath. While the chip itself might be cheap to manufacture, its going to run into the same problems that have plagued immunochromatographic diagnostic technologies for years:
1. Antibodies are extremely expensive relative to other reagents that can be used (acid fast staining for mycobacteria, nucleic acid stains for plasmodia and other parasites, etc).
2. Its impossible to get a measure of the "confidence" of a measurement using this type of technology, so verifying results requires performing a completely different diagnostic test. But if you have no idea which tests gave confident results and which did not, how do you know which results to verify?
3. Cell-phone cameras are useless for quantitative analysis, especially ones that would need high dynamic range and high accuracy
4. Quality control and assurance is a bitch. Ask any epidemiologist that has experience working with malaria RDTs in the field. Some of them last 6 months, some last 1 month on the shelf.
5. In high-burden areas for certain diseases, using a disposable test methodology becomes extremely cost-ineffective.
While this might be interesting for things like simple urine tests or blood sugar tests, diagnosing infectious diseases represents a massive challenge for technologies like this. There's a reason we still use century-old microscopy-based technologies for diagnosing things like active TB and malaria even though they suck. I don't blame the researchers, they do good work and aren't focused on building a real product. Its the journalists that somehow make the leap between "we can detect glucose" and "revolutionary diagnostic technology."
And yes, IAABME.