Inspired by women in science
Lucks and his team call this testing platform “RNA output sensors activated by ligand induction.” But his team has nicknamed it ROSALIND for short, in honor of famed chemist Rosalind Franklin, who discovered the DNA double helix alongside James Watson and Francis Crick. Franklin’s 100th birthday would have been later this month (July 25).
“Her work essentially eventually enabled us to learn how to reprogram DNA to act in our technology,” Lucks said.
When starting this project, Lucks took inspiration from another woman scientist in his life: his wife, Northwestern anthropologist Sera Young, who studies global food and water security and the role of household water insecurity in societal well-being.
“Sera researches how poor water quality impacts people’s daily lives,” Lucks said. “People tend to go to the most convenient sources to get water. But if they knew that water was contaminated, they might choose to travel farther to find safer water. We want everyone to have the tools they need in order to make informed decisions.”
ROSALIND in Paradise
To test the new platform in the field, Lucks, Jung, Alam and fellow Northwestern professor Jean-Francois Gaillard visited Paradise, Calif., at the end of last year. One year earlier, a string of massive wildfires obliterated the northern California town, destroying nearly 19,000 buildings and displacing most of its population. Gaillard, a professor of environmental engineering, is an expert in the biogeochemical processes that affect metals in the aquatic system.
“Wildfires basically melted the town,” Lucks said. “They burned down buildings and melted cars that released toxic metals into the environment.”
Lucks, Gaillard and their teams tested ROSALIND alongside gold-standard water tests and discovered that ROSALIND was able to identify the presence of elevated toxic metals in the water supply. It also provided much faster and less expensive results.
“It shouldn’t take days to get an answer to the simple question: ‘Is my water safe to drink?’” Khalid Alam, CEO of Stemloop said.
Lucks and his team envision that ROSALIND could help recovery efforts like the one in Paradise, in which residents needed to perform tens of thousands of tests in order to know if their community was safe to re-enter.
“Laboratory testing doesn’t scale,” Alam said. “It shouldn’t take days to get an answer to the simple question: ‘Is my water safe to drink?’”
Difficulties of testing at home
Disasters, of course, aren’t the only causes of unsafe water. Heavy metals, such as copper and lead, that are naturally found in the environment can leech into pipes, contaminating household water taps and school drinking fountains. Personal care products, such as sunscreens and lotions, wash off people’s skin and end up in waterways. Unused pharmaceuticals and agricultural herbicides, too, run off into our water and end up in our sinks.
But, unless we can directly — and regularly — test for these pollutants, there’s no way to maintain a peace of mind.
When testing water in their own home in Evanston, Illinois, Lucks and Young noted several difficulties. Consuming high levels of copper over many months or years can lead to liver damage and even death. With this concern, Lucks decided to check the copper levels in their household water. It cost $150 and took a month to receive the results.
“This is a one-time test,” Lucks said. “It doesn’t allow for checking levels from different taps in the house or temporal testing over time.”
Testing for lead wasn’t much easier. Lead-testing kits are available at most hardware stores. But after filling a tube with water, it still must be mailed to a centralized facility. It still costs up to $150 per test and takes weeks for results. And if people want to check their water for other contaminants, such as antibiotics, tests simply do not exist for consumers.
“There has been a lot of advances in developing point-of-use diagnostics for monitoring pathogens,” Jung said. “But not nearly enough effort for detecting chemical contaminants.”
“To ensure access to safe and clean drinking water, we need technologies that will allow easy monitoring of water quality,” Lucks said. “With a simple, easy-to-use, handheld device like ROSALIND, you can test the water in your home or out in the field — where you would want to use it most.”
The research, “Cell-free biosensors for rapid detection of water contaminants,” was supported by the National Science Foundation (award numbers 1452441 and 1929912), the National Institutes of Health (award number R35 GM118157), the Crown Family Center for Jewish and Israel Studies at Northwestern University and Searle Funds at The Chicago Community Trust.
SOURCE: Northwestern University