Scientists at Northwestern University have developed a handheld device that reprograms the building blocks of life – RNA, DNA and proteins – to test whether water is safe to drink.
The powerful devices use genetic networks – which mimic electronic circuitry – to test for water contamination and can produce results in minutes.
Development details have been published in the journal Nature Chemistry Biology Thursday.
The device is built around eight small test tubes, which glow green when a contaminant is detected by the genetic network. If only a small amount of contaminants are detected, only one tube will light up. If there is heavy contamination, all eight tubes will glow, similar to how the clicks of a Geiger counter increase in frequency as radiation levels increase.
“We programmed each tube to have a different contamination threshold,” said Julius B. Lucks of Northwestern, who led the research. “The tube with the lowest threshold will light up all the time. If all the tubes light up, then there is a big problem. Circuit construction and programmable DNA computation open up many possibilities for d ‘other types of smart diagnostics.’
Co-authors of the paper include Jaeyoung Jung, Chloe Archuleta, and Khalid Alam, all of whom are scientists from Northwestern University.
The device’s technology is based on previous work done by the team, called ROSALIND, which could detect 17 types of contaminants from a single drop of water. The work was named after chemist Rosalind Franklin and is short for “Ligand Induction Activated RNA Output Sensors”.
The device was designed to glow green if contaminants exceeding Environmental Protection Agency standards were found in the water being tested.
The researchers reprogrammed the cells’ DNA, RNA and proteins to perform logical functions, which Lucks likened to “molecular taste buds”. If the machine “tastes” a contaminant at a level exceeding EPA standards, it signals the glow.
“We discovered how bacteria naturally taste things in their water,” he said. “They do it with little molecular-level ‘taste buds’.” Synthetic biology without cells allows us to remove these small molecular taste buds and put them in a test tube. We can then “reconnect” them to produce a visual signal. It glows to allow the user to quickly and easily see if there is a contaminant in the water.”
In the latest device, scientists have added a “molecular brain” that allows the device to determine different levels of contamination during testing.
“After introducing ROSALIND, people said they wanted a platform that could also give amounts of focus,” Lucks said. “Different contaminants at different levels require different strategies. If you have a low level of lead in your water, for example, you may be able to tolerate it by flushing your water pipes before using them. But if you have high levels, then you should stop drinking your water immediately and replace your water line.”
The device has many practical applications. Mr Lucks and the team of scientists said they believe the device will provide individuals with an easy way to test their own water at home.
It could also be a valuable tool for researchers in the field, for people living in countries where drinking water is more difficult to access, or for hikers and campers who want to test the potability of water sources. on the trail.
The Independent Gt