Binding constants (log Ka) and emission quenching efficiency (ΔIntb) for 2 and 3 with mononucleotides and ds-DNA/ds-RNA determined fluorometrically. Done in sodium cacodylate buffer (pH = 7.0, I = 0.05 M). Data given for referent 1 and 4 are published previously9.
| 1 c | 2 | 3 | 4 c | |
|---|---|---|---|---|
| CMP | — | 5.8 (0.7b) | 5.6 (0.3b) | 3.1 (0.2b) |
| AMP | 5.0 (0.8b) | 5.9 (0.7b) | 5.6 (0.3b) | 4.3 (0.9b) |
| UMP | 4.1 (0.6b) | 5.7 (0.2b) | 5.0 (0.7b) | 2.5 (0.4b) |
| GMP | 4.7 (0.8b) | 5.8 (0.2b) | 5.3 (0.6b) | 4.8 (0.6b) |
| ctDNA | — | 7.6 (0.3b) | 6.2 (0.1b) | 5.2c |
| p(dAdT)2 | — | 7.4 (0.2b) | 6.6 (0.3b) | 5.0c |
| pApU | — | 6.4 (0.2b) | 7.2 (0.2b) | 5.1c |
| p(dGdC)2 | — | 5.7 (0.3b) | 6.9 (0.2b) | 5.0c |
a
The best fit of experimental data was obtained for 1 : 1 stoichiometry of dye/NMP complex or for DNA/RNA by processing of titration data by means of Scatchard equation gave values of ratio n[bound dye]/[DNA/RNA] = 0.1 and 0.2, for easier comparison all log K values were re-calculated for fixed n = 0.2.
b
ΔInt = Int(100% complex)/Int0.
c
Published data.9 For DNA/RNA log K values estimated from competition experiments.