The prototype smartphone-based detection system. (Photos courtesy of Professor Mei et al;
the images first appeared in their paper in Biosensors and Bioelectronics.
(October 15, 2015) New detection system could be used to find drugs, contaminants and bacteria
Take two things many of us have at home – paper and a smartphone – and what do you get? Well, for one group of researchers in China and Singapore, a reusable device for on-the-spot detection of pesticides.
Detecting molecules like pesticides in food or contaminants in drinking water can be time-consuming and expensive, and the equipment can be restrictively large. As a result, the detection of drugs, contaminants, bacteria and proteins in samples is usually done in a laboratory. But as healthcare moves from hospital to home and people need access to quick diagnostics in the field, detection systems need to be made more portable.
Rising to the challenge, researchers at Hefei University of Technology in Chinaand the National University of Singapore have developed paper sensors that can be analyzed using an Android program on a smartphone – an almost pocket-sized device that could detect chemicals like pesticides rapidly and cheaply. Their study, published in Biosensors and Bioelectronics, describes the new approach they have taken to making a system that can detect low concentrations of pesticide – and potentially any substance – in a sample.
Hacking consumer technology
According to telecommunications company Ericsson, there could be more than 6 billion smartphones in use by 2020 – almost one for every person on the planet. Smartphone technology is portable, accessible and relatively cheap so the researchers aimed to tap into that for their detection system.
“Since detectors are usually big, it was important that we could develop a smaller unit that was powerful enough to detect small concentrations of the pesticide,” said one of the authors of the study, Dr. Qingsong Mei, an Associate Professor in the School of Medical Engineering at Hefei University of Technology in China.
To make the detector, the researchers had to develop three components: nanoparticles to detect the pesticide and emit a fluorescent signal on the paper, a 3D-printed piece of equipment made of a smartphone attached to a mini-laser, an optical filter and a mini-cavity, and a piece of software that runs on Android.