“Our long-term motivation is to enable small, low-resources laboratories to generate their own libraries of plug-and-play diagnostics to treat their local patient populations independently,” Anna Young, co-director of MIT’s Little Devices Lab which developed the modular blocks, said in a press release.
The blocks, called Ampli blocks, are being used to create device to detect cancer, Zika virus and other infectious disease. The MIT researchers say that the blocks are inexpensive and cost about 6 cents for four blocks. They do not need to be refrigerated or have special handling, which means they can be beneficial in developing countries.
“We see these construction kits as a way of lowering the barriers to making medical technology,” Jose Gomez-Marquez, co-director of the Little Devices Lab and senior author on the study, said.
There have been a number of paper-based diagnostic tests and tests that cost less than a dollar to make developed in the last few years. Researchers have also been developing tests based on chemical reactions on paper strips with lateral flow technology, much like the technology behind pregnancy tests.
Many of those diagnostic tests have not been widely deployed, according to the MIT researchers. One of the biggest challenges is that the devices are not designed to be manufactured on a large scale. Another problem is that companies are not really interested in mass-producing a diagnostic test for diseases that only affect a small portion of the population.
The MIT researchers discovered that they can bring diagnostic tests to more people if they designed them in a kit with modular components that can be put together to create exactly what a user needs.
So far, the researchers have created about 40 different building blocks that labs around the world can assemble on their own, much like when people built their own radios and electronic devices from electronic “breadboards” in the 1970s.
“When the electronic breadboard came out, that meant people didn’t have to worry about building their own resistors or capacitors. They could worry about what they actually wanted to use electronics for, which is to make the entire circuit,” Gomez-Marquez said.
The MIT-developed components have a sheet of paper or glass fiber pressed between a plastic or metal block and a glass cover. The blocks are about half and inch on each side and are able to be snapped together along each side as well. Some of the blocks may feature channels for samples to flow through, while other blocks may have turns and can get a sample from a pipette.
Ampli blocks can perform a number of biochemical functions. They can contain antibodies that can detect different molecules in blood and urine samples. The antibodies connect to nanoparticles that change color if a certain molecule is present.
The blocks can be arranged in different configurations depending on the diagnostic device a user wants to create based on one reaction or a series of reactions. They are also color-coded by function for easy assembly of predesigned devices using instructions that the researchers post online.
The researchers suggest that Ampli blocks can outperform other versions of paper diagnostic devices. They found that they were able to run a sample back and forth over a test strip multiple times to enhance the signal which in turn could result in reliable ruin and saliva samples that can typically be more dilute than blood samples.
Now the MIT researchers are working on human papilloma virus, malaria and Lyme disease tests, as well as blocks that can synthesize compounds like drugs and blocks that use electrical componenets like LEDs. They hope to eventually look in to large-scale manufacturing techniques and launch a company to manufacture and distribute the Ampli block kits around the world.
Ampli blocks have already been sent to labs in Chile and Nicaragua to develop devices that monitor patient adherence to TB treatment and to test for a genetic variant that makes malaria more difficult to treat. The goal behind the building blocks is to get diagnostic tests into small labs in industrialized and developing countries to lab workers can make their own diagnostic tests.
“By reducing the barriers to designing new point-of-care paperfluidics, the work invites non-experts in and will certainly result in new ideas and collaborations in settings all around the world,” said Catherine Klapperich, associate dean for research and associate professor of biomedical engineering at Boston University, who was not involved in the research. “The practical demonstrations of the system presented here are poised to be immediately useful, while the possibilities for others to build on the tool are large.”
The research was funded by a gift from Autodesk and the U.S. Public Health Service.