A Boston-based company has developed paper diagnostic strips that cost just penniesto create and can be used in the developing world.
With just a drop of blood from a thumb prick, the strips developed by Diagnostics for All can detect liver damage, which is often a side effect of multi-drug AIDS and Tuberculosis treatments. In the United States, such patients are monitored with regular blood tests, but those tests are often too expensive to perform regularly in the developing world.
The company has also developed a test for aflatoxin, a mold toxin that grows on grains and can stunt development in children. Current tests, priced at $6, are too expensive for farmers in rural parts of Africa and Asia , but the new diagnostic strips can be manufactured for 50 cents or less, The New York Times reports. Another test can find spoiled milk, which can contaminate large batches if not caught early in production.
The strips use the fibers of the paper to guide sample fluids—whether blood or milk—to reagents on the strip that change colors when particular chemicals or contaminants are present. The paper tests were developed with a $10 million grant from the Bill and Melinda Gates Foundation.