Cornell engineers creating handheld pathogen detectors

A team of engineers at Cornell University are developing a handheld pathogen detector to assist healthcare workers in diagnosing cases of tuberculosis, gonorrhea and HIV.

Professors Dan Luo and Edwin Kan are one of 12 teams that received a portion of $25 million in funding from the Bill & Melinda Gates Foundation to develop point-of-care diagnostics. They describe their device, which can display results in as little as 30 minutes, a molecular-level Lego builder, according to

Luo has been developing a means of using synthetic DNA to amplifying pathogen DNA, RNA or proteins, while Kan has been building a computer chip that can respond quickly in the presence of those amplified samples.

Because single strands of DNA match up with other single strands that have complementary genetic codes, the Luo can synthesize strands that will match those of a given pathogen. The synthesized strand, which is Y-shaped, also has a molecule attached to one of its arms that assures it will link up with other molecules in the presence of ultraviolet light.

When the Y-DNA is present in a sample containing a pathogen, long chains of the combined molecule form together into large masses, a process called a polymer chain reaction. Kan's computer chip can then measure the sample's mass and charge and determine which pathogen is present, reports.

Conceivably, the chip could be controlled by a handheld phone. Luo and Kan hope to use the new technology to design a kit for healthcare workers operating in the developing world.