Fig. 1: FRETfluor concept and design.
a, FRETfluor design for ABN constructs (A strand, cyan; B strand, blue; unpaired bases, orange), shown here with a bridge (green) for the sequence-specific labelling of nucleic acids. b, FRETfluor design variations ABsk, AcB and ABin, used to create additional unique spectroscopic signatures. Key changes for each construct are highlighted with a dotted red circle. c, Bulk emission spectra of ABN constructs demonstrate that FRET tunes the emission, as expected. d, Fluorescence lifetime measurements of aggregated single-molecule data show that the Cy3 lifetime depends on the local DNA sequence and attachment chemistry (single-exponential fits are shown in solid lines; data, open circles; IRF, grey dotted line).
