Origami-Inspired Paper Sensor Could Test for Malaria and HIV for Less than 10 Cents, Report Chemists

March 8, 2012

AUSTIN, Texas — Inspired by the paper-folding art of origami, chemists at The University of Texas at Austin have developed a 3-D paper sensor that may be able to test for diseases such as malaria and HIV for less than 10 cents a pop.

This origami-inspired paper sensor, developed by chemists Hong Liu and Richard Crooks, can be easily assembled by hand. It may soon be able to inexpensively test for diseases like malaria and HIV. Photo by Alex Wang.

Such low-cost, “point-of-care” sensors could be incredibly useful in the developing world, where the resources often don’t exist to pay for lab-based tests, and where, even if the money is available, the infrastructure often doesn’t exist to transport biological samples to the lab.

“This is about medicine for everybody,” says Richard Crooks, the Robert A. Welch Professor of Chemistry.

One-dimensional paper sensors, such as those used in pregnancy tests, are already common but have limitations. The folded, 3-D sensors, developed by Crooks and doctoral student Hong Liu, can test for more substances in a smaller surface area and provide results for more complex tests.

“Anybody can fold them up,” says Crooks. “You don’t need a specialist, so you could easily imagine an NGO with some volunteers folding these things up and passing them out. They’re easy to produce, so the production could be shifted to the clientele as well. They don’t need to be made in the developed world.”

The results of the team’s experiments with the origami Paper Analytical Device, or oPAD, were published in October in the Journal of the American Chemical Society and last week in Analytical Chemistry.

The inspiration for the sensor came when Liu read a pioneering paper by Harvard University chemist George Whitesides.

Whitesides was the first to build a three-dimensional “microfluidic” paper sensor that could test for biological targets. His sensor, however, was expensive and time-consuming to make, and was constructed in a way that limited its uses.

“They had to pattern several pieces of paper using photolithography, cut them with lasers, and then tape them together with two-sided tape,” says Liu, a member of Crooks’ lab. “When I read the paper, I remembered when I was a child growing up in China, and our teacher taught us origami. I realized it didn’t have to be so difficult. It can be very easy. Just fold the paper, and then apply pressure.”

Within a few weeks of experiments, Liu had fabricated the sensor on one simple sheet using photolithography or simply an office printer they have in the lab. Folding it over into multiple layers takes less than a minute and requires no tools or special alignment techniques. Just fingers.

Crooks says that the principles underlying the sensor, which they’ve successfully tested on glucose and a common protein, are related to the home pregnancy test. A hydrophobic material, such as wax or photoresist, is laid down into tiny canyons on chromatography paper. It channels the sample that’s being tested — urine, blood, or saliva, for instance — to spots on the paper where test reagents have been embedded.

If the sample has whatever targets the sensor is designed to detect, it’ll react in an easily detectable manner. It might turn a specific color, for instance, or fluoresce under a UV light. Then it can be read by eye.

“Biomarkers for all kinds of diseases already exist,” says Crooks. “Basically you spot-test reagents for these markers on these paper fluidics. They’re entrapped there. Then you introduce your sample. At the end you unfold this piece of paper, and if it’s one color, you’ve got a problem, and if not, then you’re probably OK.”

Crooks and Liu have also engineered a way to add a simple battery to their sensor so that it can run tests that require power. Their prototype uses aluminum foil and looks for glucose in urine. Crooks estimates that including such a battery would add only a few cents to the cost of producing the sensor.

“You just pee on it and it lights up,” says Crooks. “The urine has enough salt that it activates the battery. It acts as the electrolyte for the battery.”

For more information, contact: Daniel Oppenheimer, Hogg Foundation, 512 745 3353.

11 Comments to "Origami-Inspired Paper Sensor Could Test for Malaria and HIV for Less than 10 Cents, Report Chemists"

1.  Nandkumar Chodankar said on March 10, 2012

This is really very good for the Nations where there are poor people suffering from Malaria. If this can be manufactured in India I am willing to put in all that is required. Let me know how to proceed.
Nandkuamr

2.  Adavydov said on March 13, 2012

They said the production costs are about 10cent. Nobody said anything bout the prize it will be sold for by the pharma industry. My guess would be 10 bucks for each one just to secure the profit, the patent rights, cost for labs and so on...

3.  jorge mendoza said on March 17, 2012

por el costo seria bueno implementarlo en colombia

Por favor envieme mas detalles

4.  Bill said on March 18, 2012

Fascinating! Goes to show what good ideas can bring about. I hope this takes off and helps the entire world. Good luck, guys.

5.  Rachel L McGruder said on March 19, 2012

This is truly exciting news! What a gift to the entire world - excellent work, guys!

6.  Marsha Beckermann said on March 22, 2012

Thanks for a snapshot of the inspired research happening on our campus - changing the world daily!

7.  Doug Hensley said on March 22, 2012

Before predicting that the price to the user will be ten dollars, or name your figure, why not ask the inventors about their plans?

The (American, in each case) inventors of the laser gave it to the world for free or nearly free. Same with genetically engineered, short-stalk rice. Same with polio vaccine.

It costs money to distribute things; the price in Texas cannot be the same as the price in Timbuktu. But that won't send the cost to ten dollars.

8.  George Tait said on March 22, 2012

Not everyone is a sports fan. So often communications to alumni use the incentive of coming together for a football game, or a tail gate party [my Fraternity[. I could care less.
Articles like this make me proud of my University and my state.
Thank you for these informative letters.
George L Tait, BA MA

9.  Holly said on March 22, 2012

The possibilities are thrilling! I am in awe of true genius at work. Praying this project is successful and the product is made available to the people who need it most.

10.  Keiko Miura said on March 25, 2012

Really good idea and example to follow for all of us, technology should be here to make our life simple, easier.

11.  Hjalmar Inqvist said on March 27, 2012

Wow. That's good work.

You're doing the species proud, people.