Using a customised, low-cost 3D printer, researchers at University of Minnesota printed an electronic circuit directly on to the skin of a person. Such printed circuits can now be used by soldiers, for instance, to print a sensor on their hands which can alert them as to whether a chemical or biological weapon is being used. They can carry the tiny printing device and print it out by themselves in a short time. The special ink uses silver flakes, and it can be cured and made to conduct at room temperature unlike earlier 3D printer inks which required high temperatures. Further, the device can simply be peeled off with tweezers or washed off with water. Other than electronics, the low-cost printer can be used to heal skin wounds – this process was tested on mice.
