New DNA computer assesses water quality

A low-cost, easy-to-use device that can let users know if their water is safe to drink has been developed by the University.

The new device uses genetic networks, which mimic electronic circuits, to perform a range of logic functions.

The researchers engineered cell-free molecule into anADC, a ubiquitous circuit type found in nearly all electronic devices. In the water -quality device, the ADC circuit processes an input and creates a visual signal to inform the user.

The journal Nature Chemical Biology will publish the research.

The device glows green when it finds a contaminant. The number of tubes that glow depends on the amount of contamination. The water sample has a trace level of contamination if only one tube glows. The water is contaminated if all eight tubes glow. The higher the concentration, the higher the signal.

Julius B. Lucks, who led the research, said that the tube with the lowest threshold will light up all the time. There is a big problem if all the tubes light up. There are many possibilities for other types of smart diagnostics that can be built with circuits and DNA computing.

The Center for Synthetic Biology is a part of the McCormick School of Engineering where Lucks is a professor. The paper's co-authors are from the same university.

Meet ROSALIND.

The new system builds off work that Lucks and his team published in July 2020. In that work, the team introduced ROSALIND, which could sense 17 different contaminants in a single drop of water. The test glowed green when it detected a contaminant that exceeded the U.S Environmental Protection Agency's standards.

Lucks and his team used synthetic biology to develop ROSALIND. Synthetic biology takes the machinery out of cells and reprograms it to perform new tasks. The inner workings of ROSALIND were likened to taste buds.

He said that they found out howbacteria taste things in their water. We can re-wire them to produce a visual signal. It glows to let the user see if there is a problem with the water.

The brainpower of a molecule.

In the new version,Lucks and his team have added amolecular brain.

The initial platform was a bio-sensor that acted like a taste bud. The output of the bio-sensor feeds into the genetic network, which works like a brain to perform logic.

The reprogrammed brains are put into test tubes. Adding a drop of water to each tube sets off a network of reactions and interactions that cause the freeze-dried pellet to glow.

Lucks and his team demonstrated that the new system could detect zinc, an antibiotic and an industrial metabolite. It is important to give the level of contamination rather than a simple positive or negative result.

He said people wanted a platform that could give concentration amounts. If you have a low level of lead in your water, you might be able to tolerate it if you flushed your water lines. If you have high levels, you need to stop drinking the water and replace the water line.

Helping individuals.

Lucks and his team hope to give people the ability to test their water on a regular basis. That may become a reality with inexpensive, hand-held devices like ROSALIND.

It is clear that we need to enable people with information to make important decisions. People need at- home tests to get the information they need quickly. It is similar to water. Water quality needs to be measured frequently. It is not a one-time thing because the levels can change over time.

The study was published in Nature Chemical Biology.

More information: Julius Lucks, Programming cell-free biosensors with DNA strand displacement circuits, Nature Chemical Biology (2022). DOI: 10.1038/s41589-021-00962-9. www.nature.com/articles/s41589-021-00962-9 Journal information: Nature Chemical Biology , Nature Biotechnology Citation: New DNA computer assesses water quality (2022, February 17) retrieved 18 February 2022 from https://phys.org/news/2022-02-dna-quality.html This document is subject to copyright. Apart from any fair dealing for the purpose of private study or research, no part may be reproduced without the written permission. The content is provided for information purposes only.