Right now, if a technician working in a lab in rural Angola needs to run a test to see if a patient is infected with Zika or Ebola, they’ll likely use a paper test imported from somewhere else–and if that test doesn’t work for the local population, or if it’s too expensive to buy, there may be no other option. But a new Lego-like kit is designed to make it possible for technicians anywhere to make, and tweak, diagnostics themselves.
The tiny kit called Ampli, uses modular blocks that can be connected in different patterns to replicate the function that would typically be built into a manufactured test for pregnancy, glucose, or an infection or other disease. Pregnancy tests made by a medical device company, for example, use an antibody added to a paper strip that reacts to a hormone that women produce when pregnant, and that reaction causes the paper to change color. The new blocks can create the same test without the complexity of embedding elements in paper ahead of time. It can also perform tests that are typically done with test tubes in a lab, such as a test that carefully mixes three chemicals to see if someone has taken medicine for TB. With the kit, no lab is needed, and the test costs $1.
One type of block is designed to collect a sample of blood or urine from a patient. Another type has a tiny channel for samples to flow through; a third type has turns that make multiple reactions possible. After arranging the blocks, someone working in a lab can sandwich a tiny sheet of paper in the kit, run the test with their sample and chemicals they have in the lab (the paper will turn different colors depending on the result), and then sterilize the blocks to reuse them again.
Existing paper tests are too complicated to replicate or alter, says Jose Gomez-Marquez, codirector of the Little Devices Lab, a lab at MIT that explores the design and invention of DIY health tech, and which created the new kit. “There’s all sorts of material science involved,” he says.
The researchers first focused on developing cheap paper tests themselves. But as they traveled to different countries, they noticed how common small labs were. “We call them mom-and-pop labs–they’re in the neighborhood, and they’re essentially as ubiquitous as a coffee shop or a bodega is in a Mexican city.” The labs often don’t have much equipment. But they have an employee with technical knowledge. “That means that I don’t have to prepackage all the engineering at MIT,” he says.
Regular paper tests can’t easily be adapted, and might not work in some populations; a malaria test for India might not work for a type of malaria that occurs in Kenya. They can be expensive–glucose tests, which are meant to be used by diabetics after each meal, can cost $15 per test. They also aren’t economic to manufacture at low volumes. A concept for a cheap paper test developed in a lab might not ever make it into the real world because it doesn’t make sense to start a biotech company for a tiny market.
With the new kit, it’s possible to cheaply make a test for even one patient. The basic kit costs 50¢ (when it’s reused, a lab will eventually need to buy new reagents and paper).
The kit uses proven, validated testing procedures. The simple colored blocks are designed to make it easier to put a test together in the correct way. For existing tests, someone would look at scientific literature to find instructions for the testing process, and then put the corresponding blocks together. The researchers are developing an image recognition system that could tell someone if they’re following the correct sequence. People working in labs could also develop new tests themselves. Someone working in a country with a Zika outbreak might develop their own test for the virus, checking their accuracy the way that researchers would elsewhere, by running samples that are known to be positive or negative.
“I firmly believe, and I’ve seen it in our work and then in others’ work, that there are local innovators in these countries and they are good biologists,” says Gomez-Marquez. “They will have much more readily available access to a dengue or Zika or an Ebola patient than I will ever have at MIT. In order for me to get access to a patient, I have to write up an IRB, an ethics approval, making sure I’m not going to contaminate America on the way back.”
At the height of the Ebola crisis, the MIT researchers had developed an Ebola test that would cost roughly $2. Another on the market was $25. But when the researchers reached out to the World Health Organization, explaining that they had a peer-reviewed test and wanted to share it, they were given bureaucratic excuses; the affordable test wasn’t used. Gomez-Marquez says that similar tests sent to the crisis areas by the Pasteur Institute sat in boxes and were never used.
With the new kit, he says, technicians in local labs could have made the tests themselves. “Had they had those tools on site, they would have not asked for permission from anybody,” he says. “They would have just treated. And it would have been much, much faster.”
The researchers are in the process of assembling a team and resources to manufacture the kits at scale, and plan to launch a small startup to deliver the kits around the world. Little Devices Lab is partnering with labs in Nicaragua, Chile, Honduras, Senegal, and also Spain and the U.S., where even well-equipped labs can’t easily make paper tests. Free kits will also be provided to select labs in other communities.
“Our hope is that when the next Ebola crisis happens, god forbid, and the American and European doctors fly in and hand somebody a paper test and say, ‘This is high tech stuff . . . it’s $20,’ our dream is that someone can pull a test out of their own pocket and say, ‘Well, yeah, we made this last week, it’s $2, and it does the same thing.'”