Turns out diamonds have powers beyond bringing bling-happy jewellery enthusiasts and hopeful lovers to their knees. Harvard researchers have figured out how to make the shiny little pebbles into the world's tiniest thermometers. How tiny? Small enough to take the temperature of an individual cell.
While you might call it "ice" (and please, if you do, stop) diamond is actually an excellent heat conductor. When blasted with green laser, nitrogen impurities inside diamond particles emit red light that changes intensity depending on temperature. This behaviour, discovered accidentally by researchers studying quantum computing, led scientists to inject nano-sized diamond crystals into cells and analyse the red light to measure internal temperature. They found that the diamond thermometers are 10 times as sensitive as other techniques, able to detect changes as small as 0.05C. The diamond particles can even let scientists compare temps between two parts of the same cell.
Aside from being straight up sci-fi cool, the ability to take a cell's temperature could help researchers learn more about everything that goes on inside a cell's membranes, from nutrient metabolism to DNA replication. And imagining a lab-coated professor shouting "this thermometer is now DIAMONDS" just makes it all that much cooler. [Nature]