Fig. 2. A linear relationship between the emission intensity and the number of CF on a single DNA origami scaffold (rec-Ori). (a) Illustrations of a series of rec-Ori loaded with various numbers of CF molecules (0: rec-0; 1: rec-CF1; 3: rec-CF3; 5: rec-CF5; 10: rec-CF10; 15: rec-CF15). (b) Fluorescence emission spectra of a series of CF loaded rec-Ori with excitation at 470 nm. (c) A plot of fluorescence emission intensities of a series of CF loaded rec-Ori at 518 nm against the number of CF assembled on each rec-Ori (5.0 nM) in a buffer (pH 7.6) containing 40 mM Tris–HCl, 20 mM acetic acid, and 12.5 mM MgCl₂ at ambient temperature.