Brock bot detects TB treatment resistance
A new Brock University bot is detecting resistance to tuberculosis treatment faster than before possible.
The nanomachine recognizes resistance to TB within one hour, whereas traditional treatment takes two to six weeks, the university says.
The university’s bot is 20 nanometres, or the size “about 1 out of 1,000 of (one strand of ) your hair,” says assistant professor of chemistry Feng Li, who heads up a research team at the school.
He says it’s made of up several components, including DNA strands which are attached to a 20-nanometre particle made out of gold.
Li says a first line of antibiotics can kill most of TB unless there is a serious infraction, in which case patients move to a second line of drugs.
However, if patients discontinue the treatment, it “breaks balance between drugs and the bacteria” and the bacteria grow, mutate and become resistant to the drug, says Li.
He says patients discontinuing TB antibiotics is quite common because the treatment lasts six months to a year. In addition, Li says, some patients may have the genetic mutation that makes them resistant to TB treatment even without influence from antibiotics.
In either case, it’s important to
recognize the resistance as soon as possible to change the line of treatment. While the disease is not being treated it “worsens in patients, who can also pass the disease along to others,” said a release from the university.
Alex Guan Wang, one of the grad students on Brock’s bot project, created a mathematical model to design long DNA strands to “seek out differences in nucleotides contained within the tuberculosis bacteria’s genes.”
A nucleotide is the basic structural unit and building block for DNA, and it’s within these that mutations caused by drug resistance would be found, the university says.
Yongya Li, the other grad student on the team, conducted lab experiments for the project. To test the machine, short DNA strands attached to the nanomachine carry fluorescent signal reporters.
“The nanomachine is dropped into serum extracted from human blood. If the long strands detect the mutations found in specific nucleotides, the machine turns on and glows; if the sample is disease-free, the robot remains off,” says the release.
The bot is a continuation of a 2016 machine — a three-dimensional DNA nanomachine — which detects diseases in a blood sample within 30 minutes.
The next step is clinical trials. The team is also considering commercializing the machine.