Pen with Bioink for Building Sensors

Here is a pen filled with a high tech ink that lets you create your own sensors. You can draw sensors on the body or other objects. The bio-inks react with several chemicals, including glucose, so you can use this pen to draw sensors to measure glucose directly on the skin. You can also draw on leaves to measure pollution. How cool is that? A team from the University of California, San Diego is behind this idea:

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