New latent tuberculosis test promises to be cheap and fast

May 22, 2012
This microfluidic chip invented at UC Davis uses DNA, coated on the gold spots, to test for gamma interferon -- a test for latent TB infection. The test promises to be cheaper and faster than existing tests. Credit: Ying Liu, UC Davis

Biomedical engineers at UC Davis have developed a microfluidic chip to test for latent tuberculosis. They hope the test will be cheaper, faster and more reliable than current testing for the disease.

"Our assay is cheaper, reusable, and gives results in real time," said Ying Liu, a research specialist working with Professor Alexander Revzin in the UC Davis Department of Biomedical Engineering.

The team has already conducted testing of blood samples from patients in China and the United States.

About one-third of the world's population is infected with the bacteria that cause tuberculosis, a disease that kills an estimated 1.5 million people worldwide every year, according to the U.S. .

Most infected people have , in which the bacteria are kept in check by the immune system. Patients become sick only when the immune system is compromised, enabling the bacteria to become active. People with HIV are at especially high risk.

Current tests for latent TB are based on detecting interferon-gamma, a disease-fighting chemical made by cells of the immune system. Commercially available tests require sending samples to a lab, and can be used just once.

Liu and Revzin used a novel approach: They coated a gold wafer with short pieces of a single-stranded known to stick specifically to interferon-gamma. They then mounted the wafer in a chip that has tiny channels for blood samples. If interferon-gamma is present in a blood sample, it sticks to the DNA, triggering an electrical signal that can be read by a clinician.

"If you see that the interferon-gamma level is high, you can diagnose latent TB," Liu said.

The researchers plan to refine the system so that the microfluidic sensor and electronic readout are integrated on a single chip.

A has been filed for the technology, and the researchers hope the test can be commercialized after . The work was supported by the National Science Foundation.

Explore further: Breakthrough points to new drugs from nature

add to favorites email to friend print save as pdf

Related Stories

Scientists find candidate for new TB vaccine

Mar 18, 2011

Scientists have discovered a protein secreted by tuberculosis (TB) bacteria that could be a promising new vaccine candidate, they report today in Proceedings of the National Academy of Sciences. The protein could also be use ...

Smoking increases risk of TB infection, study finds

Feb 27, 2007

People who smoke have a greater risk of becoming infected with tuberculosis (TB) and of having that infection turn into active TB disease, according to an analysis by researchers at the University of California, Berkeley.

New TB test reveals patients at risk, says study

Oct 20, 2008

A recently introduced blood test can reveal which patients may develop active tuberculosis (TB) much more precisely than the 100-year old TB skin test, according to a new study published today in the journal Annals of In ...

Recommended for you

Breakthrough points to new drugs from nature

11 hours ago

Researchers at Griffith University's Eskitis Institute have developed a new technique for discovering natural compounds which could form the basis of novel therapeutic drugs.

World's first successful visualisation of key coenzyme

11 hours ago

Japanese researchers have successfully developed the world's first imaging method for visualising the behaviour of nicotine-adenine dinucleotide derivative (NAD(P)H), a key coenzyme, inside cells. This feat ...

User comments : 0

More news stories

Breakthrough points to new drugs from nature

Researchers at Griffith University's Eskitis Institute have developed a new technique for discovering natural compounds which could form the basis of novel therapeutic drugs.

A greener source of polyester—cork trees

On the scale of earth-friendly materials, you'd be hard pressed to find two that are farther apart than polyester (not at all) and cork (very). In an unexpected twist, however, scientists are figuring out ...

Down's chromosome cause genome-wide disruption

The extra copy of Chromosome 21 that causes Down's syndrome throws a spanner into the workings of all the other chromosomes as well, said a study published Wednesday that surprised its authors.