Figure 3.

Compared titrations of compound 4 by different oligonucleotides. Compound 4 was prepared at a final concentration of 100 nM, and different oligonucleotides were tested (as indicated in the key). Excitation was set at 355 nm. The total emission (520–700) was summed, and the relative fluorescence intensity (arbitrary units) is given in comparison to free dye emission. The DNA concentration is expressed in nucleotides, as these oligonucleotides have heterogenous lengths. The temperature of the sample was fixed at 20°C.