Food, water safety provide new challenges for today's sensors

Sensors that work flawlessly in laboratory settings may stumble when it comes to performing in real-world conditions, according to researchers at the Department of Energy's Oak Ridge National Laboratory.

These shortcomings are important as they relate to safeguarding the nation's food and water supplies, said Ali Passian, lead author of a perspective paper published in ACS Nano. In their paper, titled Critical Issues in Sensor Science to Aid Food and Water Safety, the researchers observe that while sensors are becoming increasingly sophisticated, little or no field testing has been reported.

"Although sensor researchers are keenly aware of the various issues challenging their particular technologies, outsiders may perceive an overestimated level of performance, or in certain cases, the availability of 'uber-sensors,'" the researchers wrote. Co-authors are Rubye Farahi and Laurene Tetard of ORNL and Thomas Thundat of the University of Alberta.

Salmonella, E-coli, pesticides and mercury are among key targets for sensors, so a clear public understanding of their capabilities - and limits - is essential, particularly because food and water make for highly complex chemical and biological environments, Passian said.

"Given the current physics of sensors, these hazards pose especially difficult challenges that will require further research and successful demonstration," Passian said.
The researchers explored paths necessary to ensure that sensors work as intended and can help protect the public - a goal they are confident can be achieved.

"While human and animal sensory capabilities are highly specific and can recognise the molecular fingerprints of many potentially harmful substances, developing similar and superior sensing capabilities is faced with many challenges for which nanoscience may provide new solutions," Passian said.