Smartphones have truly become one of the greatest scientific tools. The phones, which are actually tiny, powerful computers that fit in our pockets, have led to a boom in citizen science and researcher applications that let scientists study specimens in the field.
Another important area of use has been medicine. Smartphones could be handheld diagnostic tools that any doctor or nurse anywhere in the world could use to quickly detect diseases. A new smartphone accessory has proven that the gadgets can do just that. Biomedical engineering researchers at Columbia University have created a dongle that can diagnose HIV and syphilis from a finger prick in just 15 minutes when paired with a smartphone.
The team recently tested their device in Rwanda with a group of pregnant women in a program that aims to prevent mother-to-child transmission of diseases. The 96 women had their finger pricked and the dongle analyzed the blood. The accessory looked for the markers of the infectious diseases in a process called enzyme-linked immunosorbent assay (ELISA).Typical ELISA equipment costs about $18,450, but the smartphone dongle kit is estimated to cost about $34 to manufacture.
“Our work shows that a full laboratory-quality immunoassay can be run on a smartphone accessory,” said Samuel K. Sia, associate professor of biomedical engineering. “Coupling microfluidics with recent advances in consumer electronics can make certain lab-based diagnostics accessible to almost any population with access to smartphones. This kind of capability can transform how health care services are delivered around the world.”
The dongle when paired with the smartphone still fits in one hand and is lightweight. It also requires little power and runs off of the smartphone battery.
Columbia University says to reduce the power consumption of the device, "They eliminated the power-consuming electrical pump by using a 'one-push vacuum,' where a user mechanically activates a negative-pressure chamber to move a sequence of reagents pre-stored on a cassette. The process is durable, requires little user training, and needs no maintenance or additional manufacturing. Sia’s team was able to implement a second innovation to remove the need for a battery by using the audio jack for transmitting power and for data transmission. And, because audio jacks are standardized among smartphones, the dongle can be attached to any compatible smart device (including iPhones and Android phones) in a plug-and-play manner."
During testing in Rwanda, health care workers received 30 minutes of training and were able to successfully use the device. The device worked so well in testing that the researchers believe that this type of quick diagnostic tool could decrease deaths by syphilis ten-fold and they think that in large-scale testing for HIV, the ability to diagnose and immediately treat with antiretroviral therapy could be a major step in stopping the spread and defeating the disease altogether.