It’s the worst thing in the world when you open up a container in you fridge to find fungus growing and a stench that will leave you nauseas for hours. MIT reports some of its researchers have developed a method to produce cheap NFC based sensors that could tell if a box contains spoiled food.
The new sensor is just a modified near field communication (NFC) chip that can detect the presence of specific gases with the help of carbon nanotubes. It then shares its data with a smartphone, potentially making users aware of the soon-to-be moldy fruit in the bottom of the fridge. The functionality of the sensors is exciting. While the team of chemists who developed the technology are exploring all kinds of different uses for them, these sensors make great sense for food packaging. They can literally tell you if food has spoiled with a quick wave of a smartphone. Just the sensor and the smartphone is all you need. There have been such sensors in the past, but none that work with smartphones. NFC tags can be read by any smartpone that has near-field communication capabiligy, which is included in many newer smartphone modes. These phones can send out short pulses of magnetic fields at radio frequency (13.56 megahertz), inducing an electric current in the circuit on the tag, which relays information to the phone.
These inexpensive sensors could be widely deployed, making it easier to monitor public spaces or detect food spoilage in warehouses. Using this system, the researchers have demonstrated that they can detect gaseous ammonia, hydrogen peroxide, and cyclohexanone, among other gases.
‘‘The beauty of these sensors is that they are really cheap. You put them up, they sit there, and then you come around and read them. There’s not wiring involved. There’s no power,’’ MIT chemistry professor Timothy Swager said. ‘’You can get quite imaginative as to what you might want to do with a technology like this.’’ For several years, Swager’s lab has been developing gas-detecting sensors based on devices known as chemiresistors, which consist of simple electrical circuits modified so that their resistance changes when exposed to a particular chemical.
The MIT team that invented the sensors has applied for a patent on the technology. They are also trying to improve the technology so that the sensors work with Bluetooth, which would extend their range. They even think they could be used in badges so that employees in hazardous areas could get an alert if a dangerous gas is present.