20-Cent Device Tests for Malaria and HIV

finall233It’s no secret that in the United States and other developed countries most people have access to doctors to test for diseases, treat illnesses, and more. However, not everyone is that fortunate. Some people in underdeveloped countries don’t have access to health care for routine exams, vaccinations and other medical needs. When Manu Prakash visited Uganda he discovered just that: doctors were unable to diagnose malaria and HIV because the device needed, a centrifuge, requires electricity – something often lacking in poor countries. That’s when Prakash, an assistant professor of bioengineering at Stanford University, got to thinking, and ultimately created a low-cost version of a centrifuge – costing 20 cent.

Malaria, HIV and tuberculosis are just three examples of diseases that can use a centrifuge to test blood. A centrifuge spins blood at a high speed, thus separating the different components in the blood making it easier to detect pathogens. However, in poor regions, where these diseases are most prevalent, there has been no way to test for these diseases due to lack of electricity and resources.

Prakash teamed up with Saad Bhamla and focused on spinning toys like yo-yos and whirligigs. One night Bhamla set up a high speed camera only to discover that a whirligig rotated at an impressive 10,000 – 15,000 rpms. Prototyping lasted two weeks until blood was able to be centrifuged on a paper-disc whirligig. The result was just what they were hoping for – the blood was in layers.    

This led to engineering students from MIT and Stanford coming together to build a mathematical model for the device. According to Stanford News, “The team created a computer simulation to capture design variables like disc size, string elasticity and pulling force. They also borrowed equations from the physics of supercoiling DNA strands to understand how hand-forces move from the coiling strings to power the spinning disc.” The prototype was able to reach 125,000 rpms, and they concluded that patients could be tested for malaria in 15 minutes – which is the amount of time needed to separate parasites from red blood cells.

Prakash and Bhamla prove first hand that if people rethink the way certain objects are used it can be beneficial for millions of people suffering from lack of health care. When great minds use science to to change the way we test for and treat diseases beautiful, and simpler, advancements can be made in the fight against diseases.