© ISTOCK.COM/KTSIMAGE/ERAXIONEven the earliest scientists knew that temperature was an important vital sign, signifying sickness or health. In the 17th century, Italian physiologist Sanctorio Sanctorius invented an oral thermometer to monitor patients. Now, 21st-century researchers have set themselves a new, more challenging task: taking the temperatures of individual cells.
“Temperature is one kind of basic physical parameter which regulates life,” says Mikhail Lukin, a physicist at Harvard University who has developed a diamond-based intracellular temperature sensor. “It determines the speed of all sorts of processes which occur inside living systems.”
But although temperature is a basic vital sign, scientists have a relatively poor understanding of how it varies among and within cells. “It turns out that to measure temperature reliably inside the cell is not easy,” says Lukin. “You cannot stick a large thermometer in there and maintain the cell viability.”
In the last five years, however, researchers have drawn on nanotechnology to create miniature thermometers that can reveal temperature heterogeneity both between cells and within them. “I can identify 2010, or around 2010, ...
