To understand the mechanisms by which molecules act in cells, or the effects of drugs on them, it would be ideal to be able to track individual molecules, including where in the cell they are located and what modifications they undergo when conditions in the cell change. However, this has proven difficult with existing technologies, particularly given the amount of time required to perform such monitoring.

A research team centered at Osaka University, in collaboration with RIKEN, has developed a system that can overcome these difficulties by automatically searching for, focusing on, imaging, and tracking single molecules within living cells. The team showed that this approach could analyze hundreds of thousands of single molecules in hundreds of cells in a short period, providing reliable data on the status and dynamics of molecules of interest.

For the development of this method, reported in the journal Nature Communications, the team used an artificial intelligence-based system, involving the training of neural networks to learn to focus correctly on a sample and to automatically search for cells, followed by the tracking of single fluorescently labeled molecules with a total internal reflection fluorescence microscope.