Engineers develop novel biosensor for use on teeth
PRINCETON, N.J., USA: Princeton University researchers have successfully tested a special kind of biosensor that could help to prevent disease by detecting even small amounts of harmful bacteria more quickly than conventional methods. Using a "tattoo" made from silk and gold and attached to a cow's tooth, they were able to successfully transmit a signal wirelessly to a nearby receiver.
With the method, developed in collaboration with the U.S. Air Force and the American Asthma Foundation, the researchers hope one day to be able to detect not only bacteria but also DNA or particular viruses. In lab tests conducted at Princeton's School of Engineering and Applied Science this year, they were already able to detect pathogens responsible for surgical infections and stomach ulcers, among others.
The signals are received from a gold antenna on the tattoo that is attached to an array of graphene — very small particles of carbon — that triggers a signal when in contact with bacteria through attached proteins called peptides. Therefore, the device does not require any power supply, the researchers said.
The sensor is held in place by a water-soluble silk base derived from insect cocoons. In this way, the researchers said, the sensor can be used on different kinds of biomaterials, like teeth or skin, and washed away or dissolved by body enzymes after use.
According to the researchers, there is still a long way to go before such a biosensor could be in regular use, since the sensor is still too large to fit on human teeth and its lifetime and transmission distance are short. They admitted, however, that a few modifications to the design of the sensor could increase its transmission distance in the future.
Most traditional biosensors are based on substrates like silicon, which makes them heavy and uncomfortable to wear.