Table 1. Model parameters estimated by using eq. (1) to fit data for fluorescence quenching of different dye-bipy-DNA by Cu²⁺.

dye label	log K a	fPQ, bulk b	χ2	fPQ,sm c
TMR	6.95±0.05	0.05±0.002	0.9256	0.11±0.07
ATTO620	6.53±0.08	0.37±0.01	0.9552	0.17±0.08
ATTO633	6.01±0.07	0.17±0.01	1.1474	0.18±0.07

^aStability constant for probe/Cu(II) complex and.

^bquantum yield of probe/metal cation complex as determined from bulk data.

^cQuantum yield as determined from single-molecule experiments from 10–20 sample traces each.