DNA Measures Temperature: Thermometer Made From DNA
Researchers at the University of Montreal have created a thermometer that’s an astonishing 20,000 times smaller than a single human hair. It is so tiny that it can be inserted into cells to read the temperature inside.
The thermometers are only 5 nanometers in diameter and are created from nucleotides by relying on the idea that adenine binds weakly to thymine, while cytosine and guanine form a stronger bond. The molecular thermometers can be made in quantity, each folding and unfolding at different temperatures, providing the necessary resolution for detailed studies. An optical reporter attached to the molecule can be used to detect the shape of the molecules and so know the temperature nearby.
Over 60 years ago, researchers discovered that the DNA molecules that encode our genetic information can unfold when heated. “In recent years, biochemists also discovered that biomolecules such as proteins or RNA are employed as nanothermometers in living organisms and report temperature variation by folding or unfolding,” said senior author Alexis Vallee-Belisle from University of Montreal in Canada.
One of the main advantages of using DNA to engineer molecular thermometers is that DNA chemistry is relatively simple and programmable. “There are
still many unanswered questions in biology,” Vallee-Belisle said. “For example, we know that the temperature inside the human body is maintained at 37 degree Celsius, but we have no idea whether there is a large temperature variation at the nanoscale inside each individual cell,” Vallee-Belisle pointed out.This study which was published in Nano Letters is an extremely impressive achievement in its own right. The researchers believe that these nanoscale thermometers open many exciting avenues in the emerging field of nanotechnology, and may even help us to better understand molecular biology.
