‘FRET’ not – detecting cancer biomarkers using fluorescence blinking

By exploiting a ‘flaw’ in fluorescence spectroscopy, researchers from Osaka University (Osaka, Japan) can detect ultrasmall concentrations of an RNA molecule that serves as a biomarker for cancer. Using a photo-stabilizing molecule – cyclooctatetraene (COT) – as a triplet energy acceptor, researchers were able to modulate fluorescence blinking in biochemical assays. Fluorescence blinking was thus monitored as a measure of oligonucleotide dynamics at the single-molecule level, allowing for the single-molecule detection of a model microRNA biomarker. COT was used to increase fluorescence by suppressing fluorescence blinking as compared with more traditional fluorescence techniques such as fluorescence resonance energy transfer, or...