Ratiometric DNA sensing with a host-guest FRET pair

Area of Science:

• Supramolecular Chemistry
• Analytical Chemistry
• Biotechnology

Background:

• Fluorescence resonance energy transfer (FRET) is a powerful tool for molecular sensing.
• Existing DNA sensing methods, like SYBR Green I, have limitations in dynamic range and signal linearity.
• Supramolecular chemistry offers unique platforms for designing novel sensor architectures.

Purpose of the Study:

• To develop a novel supramolecular host-guest FRET pair for DNA sensing.
• To create a ratiometric sensor with enhanced linearity and a wider detection range.
• To compare the performance of the developed sensor with commercial DNA intercalating dyes.

Main Methods:

• Fabrication of a FRET pair using carboxyfluorescein-labelled cucurbit[7]uril (CB7-CF) as acceptor and 4',6-diamidino-2-phenylindole (DAPI) as donor.
• Utilizing a host-guest interaction between cucurbit[7]uril and DNA.
• Measuring dual-emission signals for ratiometric analysis of DNA concentration.

Main Results:

• The developed CB7-CF/DAPI FRET pair successfully detected DNA.
• The sensor exhibited dual-emission signals, enabling a ratiometric response.
• A linear ratiometric response was observed over a wide DNA concentration range.
• The new sensor demonstrated superior performance compared to SYBR Green I.

Conclusions:

• A novel supramolecular host-guest FRET pair based on CB7-CF and DAPI is effective for DNA sensing.
• The dual-emission ratiometric approach provides a linear response across a broad concentration range.
• This chemosensing ensemble offers a promising alternative to conventional DNA staining dyes.