Researchers designed a new sensor, which would detect pathogens in food even before it is put on shelves.
The major contamination in food occurs due to harmful bacteria such as Listeria, Salmonella, or E. coli. The FDA recalled above 100 food due to food contamination in 2017. The researchers from China Jiliang University designed a sensor that can simultaneously detect multiple substances including dangerous bacteria and other pathogens. The findings were published in the journal Optical Materials Express in December 2018.
In addition to food safety, the new design is capable of detecting gases and chemicals in better ways than the existing systems, for a wide range of other applications.
Bing-Gang Xiao, from China Jiliang University and researchers of the study, said, “Our design is based on graphene sheets, which are two-dimensional crystals of carbon just one atom thick. The sensor is not only highly sensitive but can also be easily adjusted to detect different substances.”
Using theoretical calculations and simulations, the researchers were able to design a range of nanoscale graphene disks with an off-center hole for the new sensors application. Ion-gel and silicon layers were put inside the sensor for applying voltage to tune the graphene’s properties for detection of various substances.
The researchers are focusing now to develop an improved version of the array of nanoscale discs since the accuracy at which these structures are fabricated will greatly impact the performance of the sensor. “We also want to explore whether the graphene plasmon hybridization effect could be used to aid the design of dual-band mid-infrared optical communication devices,” added Xiao.