Inside every cell, there are tiny power stations — mitochondria. They burn nutrients and store energy. Two helper molecules, NADH and FAD, oversee this process. Previously, they were detected by their faint glow, but it was dim, and signals from different molecules overlapped.
The new microscope works differently. It sends two light beams into the cell and captures the tiny heat that arises when a molecule absorbs light. It's like finding a sun-warmed coin in the grass by touch — even if it doesn't shine. This method is a thousand times more sensitive than the old one and does not confuse NADH with FAD.
Using the new microscope, scientists observed how the shape of mitochondria affects their function. They also tracked how mitochondria in cancer cells change during chemotherapy. This could help tailor treatments more precisely and monitor their effects at the level of a single organelle.
Mitochondria are the only parts of the cell (besides the nucleus) that have their own DNA. They came to us from ancient bacteria that once settled inside our ancestors.
In the series 'Star Trek,' the medical tricorder scans a patient without touching them — the new microscope does something similar for living cells, but instead of sound waves, it uses light and heat.