We found a way to film a single molecule for over 24 hours straight without it "fading out" like they usually do.
bioRxiv · March 13, 2026 · 10.64898/2026.03.13.711506
Why it matters
Normally, fluorescent labels 'burn out' (photobleach) within seconds or minutes, making it impossible to watch slow biological transitions. By using a rapid-exchange probe system, this technique allows for 24-hour uninterrupted observation of the smallest units of life.
From the abstract
Single-molecule fluorescence imaging enables direct tracking of molecular dynamics. Prolonged observation, however, is limited by photobleaching, restricting access to rare events and slow transitions. Exchangeable fluorogenic labeling has been developed to overcome this limitation, yet continuous single-molecule tracking has not been achieved. We define two quantitative kinetic conditions for continuous tracking: pre-bleach dissociation and within-frame rebinding. Mapping reported systems onto