A sweet solution for E. coli contaminated water

Canadian researchers have developed a paper strip laced with sugar which can kill E. coli in contaminated water. It is hoped the discovery — named DipTreat — will be key to developing a new generation of inexpensive and portable water treatment devices.

DipTreat is the latest innovation by researchers at York University’s Lassonde School’s Micro and Nano-scale Transport (MNT) Lab. The group has previously discovered new ways to detect E. coli in contaminated water using a mobile water kit.

“It will take less than two hours to fish, trap and kill E. coli in water,” said researcher Professor Sushanta Mitra, who heads up the lab. “We were able to efficiently remove almost 90% of bacteria by dipping the special paper strip in contaminated water samples.”

Using porous paper strips to trap the bacterial cells, the researchers used an antimicrobial agent extracted from the seeds of moringa — commonly known as drumstick or horseradish tree. As a result, the DipTreat solution uses only naturally available antimicrobial substances and sugar, with minimal environmental and health impact. Current water treatment systems use silver nanoparticles and clays, whose long-term impact on human health is yet to be fully understood, according to Professor Mitra.

So far, DipTreat is effective for small quantities of water. For example, someone who is hiking can collect a glass of water and then dip the paper strips to purify it before drinking. But researchers believe that the invention could lead to a much greater impact. Recognising the global importance of water purification technology, UNICEF invited Mitra to showcase the team’s work at a stakeholder meeting in Copenhagen on 22 November.

Published in the Royal Society of Chemistry’s journal Environmental Science Water Research & Technology, the study is co-authored by Mitra, Saumyadeb Dasgupta and Naga Siva Gunda.