Smartphone, Finger Prick, 15 Minutes, Diagnosis—Done!

A step-by-step demonstration of a smartphone dongle to diagnose sexually transmitted infections through a fully automated immunoassay
—Video courtesy of Tassaneewan Laksanasopin and Tiffany Guo for Columbia Engineering

A team of researchers, led by Samuel K. Sia, associate professor of biomedical engineering at Columbia Engineering, has developed a low-cost smartphone accessory that can perform a point-of-care test that simultaneously detects three infectious disease markers from a finger prick of blood in just 15 minutes.

The device replicates, for the first time, all mechanical, optical, and electronic functions of a lab-based blood test. Specifically, it performs an enzyme-linked immunosorbent assay (ELISA) without requiring any stored energy: all necessary power is drawn from the smartphone. It performs a triplexed immunoassay not currently available in a single test format: HIV antibody, treponemal-specific antibody for syphilis, and non-treponemal antibody for active syphilis infection.

Sia’s innovative accessory or dongle, a small device that easily connects to a smartphone or computer, was recently piloted by health care workers in Rwanda who tested whole blood obtained via a finger prick from 96 patients who were enrolling into prevention-of-mother-to-child-transmission clinics or voluntary counseling and testing centers. The work is published February 4 in Science Translational Medicine. Sia collaborated with researchers from Columbia’s Mailman School of Public Health; the Institute of HIV Disease Prevention and Control, Rwanda Biomedical Center; Department of Pathology and Cell Biology, Columbia University Medical Center; Centers for Disease Control and Prevention—Laboratory Reference and Research Branch, Atlanta; and OPKO Diagnostics.

“Our work shows that a full laboratory-quality immunoassay can be run on a smartphone accessory,” says Sia. “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.”

Read more: Smartphone, Finger Prick, 15 Minutes, Diagnosis—Done!