Molecular structure and DNA binding mode of unsymmetric cyanine dyes RiboGreen and OliGreen.

Molecular structures of RiboGreen, OliGreen, and PicoGreen reveal they are unsymmetric cyanine dyes with specific benzazolium and quinolinium components, crucial for nucleic acid detection.

• Why it matters: Understanding the precise molecular structures of these dyes fills a critical knowledge gap, enabling better interpretation of their fluorogenic behavior and improving nucleic acid imaging techniques.
• What they did: Using high-field NMR spectroscopy and mass spectrometry, the study determined the structures of RiboGreen and OliGreen, confirmed PicoGreen's structure, and analyzed their binding modes with DNA and RNA.
• The result: Findings show that RiboGreen interacts with double-stranded DNA mainly through electrostatic and π-π stacking interactions, providing insights for designing improved nucleic acid probes and imaging tools.