No war in water

A key advantage of the A “dipstick” biosensor that monitors water supplies for agents of chemical and biological warfare has been developed by a team at Ben-Gurion University of the Negev in Beersheba, Israel. The development is expected to arouse …

A key advantage of the A “dipstick” biosensor that monitors water supplies for agents of chemical and biological warfare has been developed by a team at Ben-Gurion University of the Negev in Beersheba, Israel. The development is expected to arouse interest in countries threatened by unconventional warfare and terrorism.



Robert Marks and his team from the Faculty of Engineering Sciences, the department of biotechnology engineering and the university’s Institute for Applied Biosciences, have created a bio-luminescent optical fiber probe that can be used to monitor chemical and biological warfare agents in water.



Whole bacterial cells that have been genetically engineered to react to targeted toxins, such as pesticides, are part of the probe.



Marks said he feels BGU is the ideal site to create a center for research in this field, as the world is facing a threat to its water supplies far more serious than environmental and industrial pollutants.



“Ever since the World Trade Center attack, anything is possible,” Marks said.



The BGU scientist plans to continue this research, and, with Orly Yadid-Pecht of Israel’s National Center for CMOS (Complementary Metal Oxide Semiconductor Research), he plans to create chip sensors as well.



While current systems for testing water can identify the presence of a chemical in a sample using sophisticated instrumentation, they cannot give bio-toxicity information unless they use fish or similar bacteria in sophisticated laboratories.



Marks’ device is a self-contained system to which nothing needs to be added beyond the dipstick-like probe itself. It uses specially formulated bacteria genetically engineered to produce light when they are exposed to chemicals that damage their genetic material (genotoxins).



The bacteria are gel-coated onto one end of an exposed optical fiber, forming a sensitive chemical detector. When this probe is inserted into a sample of water outdoors or in the lab, any genotoxins present in the water column cause the bacteria to glow.



The light transmitted along the optical fiber is then measured by a sensitive photodetector.



Marks said water agencies won’t have to bring water to a centralized lab for testing as is currently done, because this system allows for on-site monitoring of water. If a lab finds a high level of bio-toxicity, the technician can return to the spot the same day and repeat the test, as well as do other additional tests.



“Every water board in every state in America can take advantage of this technology,” Marks said, adding that he is developing other fiber probes that can determine whether mercury, cadmium or other types of contaminants are present.



Chemical and biological attacks on water supplies are an increasing area of concern, he said, a possibility he called “very frightening,” and said he believes his probe could be a key tool in detecting chemical and biological assaults on water supplies here and around the world.