new invention , general knowledge

Scientists develop paper made of carbon


Indian scientists have developed a composite paper made of carbon (graphene oxide) that is loaded with preservatives that can be used as fruit wrappers to help extend shelf life  can. 

It has been developed by a team of researchers from Institute of Nano Science and Technology, Mohali.

The rapper releases the preservative only when needed. Wrappers can be reused.

Unlike the present preservative dipping technology, where the preservatives are adsorbed by the fruit, causing chronic toxicity to the consumers; here the wrapper releases the preservative only when needed. The wrapper can be reused, which is not possible with the present technology.

The team led by Dr P S Vijayakumar had looked for an alternative to conventional preservation which relies on coating the preservative with the resin, wax, or edible polymer, which may cause chronic health problems.

“The high preservative-loaded graphene oxide, when cast into a paper used for fruit wrapping, ensures that the fruit is not loaded with toxic preservatives. But when the fruit over-ripens or gets infested by pathogens, the acidity increases by the secretion of acids, critic, and oxalic acids trigger the release of the preservatives for the preservation of the fruit.

The sensor, which changes colours based on the amount of carbon dioxide in the environment, has many potential applications -- from industries that make use of carbon dioxide to smart buildings. And due to its paper base, the sensor is low cost to create and provides a simple template for mass production.

"In smart buildings, carbon dioxide sensors can tell you about the occupancy and where people tend to congregate and spend their time, by detecting the carbon dioxide exhaled when we breathe," explained Meldrum. "This can help to aid in building usage and design. Carbon dioxide sensors currently can be very expensive if they are sensitive enough for many applications, so a cheap and mass-produced alternative could be beneficial for these applications."