Northwestern University researchers have developed a new system to enhance the detection of low-concentration chemicals, expanding its potential applications in environmental and human health monitoring. The innovative approach utilizes a sensing platform that is 10 times more sensitive than previous models.
The study, published in Nature Chemical Biology, highlights the adaptation of a sensing platform initially used for detecting toxins in drinking water. This advancement allows for the measurement of nucleic acids such as DNA and RNA, and bacteria like E. coli, outside laboratory settings.
"Biosensors repurposed from nature can, in principle, detect a whole spectrum of contaminants and human health markers," said Julius Lucks, corresponding author and synthetic biologist at Northwestern. "By adding genetic circuitry that acts like an amplifier, we can make this biosensing platform meet sensitivity levels needed for application in environmental and human health monitoring."
Lucks' team engineered ROSALIND using cell-free synthetic biology to sense various contaminants. Initially capable of detecting 17 different substances in water droplets, ROSALIND has been enhanced to compute contaminant concentrations.
The research team discovered a method to amplify signals using DNA nanotechnology. "We created a new system to amplify signals in ROSALIND," explained Jenni Li, first author and Ph.D. candidate. This development allows the detection of molecules at lower concentrations without altering the biosensor protein itself.
ROSALIND's latest iteration is being tested in real-world applications, including an ongoing field study detecting lead in Chicago's drinking water. Lucks emphasized the broader potential uses: "We are also developing ROSALIND to detect human health markers, food quality markers and agricultural compounds."
The work received support from multiple organizations including the National Institutes of Health and the National Science Foundation. Northwestern startup Stemloop is commercializing the technology with financial interests from both Lucks and Northwestern University.