Engineers at UC Davis have developed a microfluidic chip to test for latent tuberculosis (TB) which aims to be more reliable, faster and less expensive than current testing options available.
According to the Centers for Disease Control and Prevention, an estimated 1.5 million people worldwide are killed by the disease annually, and nearly one-third of the world’s population is infected with latent TB. Those with latent TB are at risk for the tuberculosis bacteria to become active if their immune system is compromised.
Current tests for latent TB are based on detecting interferon-gamma, a disease-fighting chemical made by cells of the immune system. The researchers at UC Davis took a novel approach to detection utilizing a gold wafer coated with short pieces of single-strand DNA segments known to “stick” specifically to interferon-gamma. Then using a chip that has tiny channels for blood samples, they mounted the wafer. If interferon-gamma is in a blood sample, it sticks to the DNA, prompting an electrical signal that can be read by a clinician. High interferon-gamma levels would be correlated to diagnose latent TB.
Such a device would allow rapid results and circumvent the need to send samples out to a laboratory. “Our assay is cheaper, reusable, and gives results in real time,” said Ying Liu, a UC Davis Department of Biomedical Engineering research specialist working with Professor Alexander Revzin on the project.
The researchers have filed a patent application for the technology. Moving forward, the team plans to incorporate the microfluidic sensor and electronic readout onto a single chip and then work towards FDA approval and commercialization of the diagnostic device.
Image provided courtesy of Ying Liu, UC Davis