A novel approach to probe temperature in living cells is reported in this week’s Nature. The ‘nanothermometer’ is based on diamond nanocrystals and can accurately measure very small temperature variations at high spatial resolution. Potential applications include temperature-induced control of gene expression, and the cell-selective treatment of diseases.
The nanoscale thermometry technique developed by Mikhail Lukin and co-workers uses quantum manipulation of nitrogen vacancy (NV) colour centres in diamond nanocrystals. These have specific fluorescence properties that are sensitively dependent on the local temperature. The authors show that they can detect temperature variations as small as 44 millikelvin using nanodiamonds and can measure the local thermal environment at length scales as low as 200 nanometres. They demonstrate temperature-gradient control and mapping at the sub-cellular level in a single human embryonic fibroblast.
These observations provide a powerful tool for biological, physical and chemical research and open up a number of interesting possibilities, including medical applications.