Nanodiamonds used to measure temperature in living cells

Nature : Researchers at Harvard University have developed a nanothermometer at least 10 times more sensitive than current devices. Their thermometer, which consists of tiny diamond crystals, takes advantage of the photoluminescent properties of diamond’s nitrogen–vacancy centers . When the nanodiamond crystals are injected into a human embryonic cell, they can be made to fluoresce with red light by illuminating the cell with green lasers. The temperature is determined by the intensity of the red light emitted. By adding gold nanoparticles to the cell and heating them with the laser, the researchers were able to precisely control where in the cell the temperature would rise and by how much. The nanodiamond thermometer could have useful medical applications, such as in the cell-selective treatment of disease.