Researchers have developed a technique that produces laser induced graphene on food, paving way for edible electronics.
Graphene has been heralded as a wonder material. We’ve already seen it being used in shoes to keep feet cool and to create temporary wearable tattoos and now researchers at Rice University have developed a way to induce graphene onto certain foods.
Graphene is a form of carbon, which has been found to be extremely strong and conductive. The team has demonstrated that under particular wavelengths, some carbon-based materials can have graphene layers scored onto them via lasers. This produces what is known as laser induced graphene (LIG). While it might look like ink, the resulting pattern is actually produced by the object itself. The scientists have used this technique to induce patterns onto various everyday objects like wood, pieces of toast, potatoes and coconut shells. The technique can be accomplished in normal air and temperature conditions. It works by passing a defocused laser multiple times over the surface of the object, which must feature certain elements such as lignin, found in the cell walls of some foods. Toast can only be patterned with graphene when it’s well browned, so that there’s more carbon molecules on the surface.
As well as being a new potential source of branding, the tantalizing aspect of the technique lies in the fact that layers of graphene placed on top of each other can produce a current. If consuming graphene layers into food is considered safe, the technique could be used to create simple ingestible circuits. According to the researchers those circuits could feature RFID tags that connect to an app, featuring information about where the food came from. They could also act as sensors to detect when potentially food-poisoning bacteria such as E. coli are present. The research has been published in ACS Nano, but as yet the group hasn’t made public any plans to attract commercial partners.
As wearables grow ever smaller and the Internet of Things (IoT) network continues to expand, what are the potential uses of graphene based micro-sensors and circuits in industry?