Figure 2. Molecular paints rapidly coat native proteins in solution.

(a–c) Association (blue) and dissociation (red) binding curves (moles of paint per mole of protein) for paint molecules (structures are shown inset) associating with CA II. Molecular paints have unusually high association rates and low dissociation rates: saturation is reached within 5 min and the off rate is <10% dissociation after 2 h. (d) Calibration data for RBB associated to CA (absorbance spectra for RBB, CA and the complex is reported in Supplementary Fig. 7). (e) Scatchard plot of CA and AO50 shows the number of binding sites to be five, confirming the saturation point of the binding kinetics in (b). (f) Scatchard plot of CA and ANSA shows the number of binding sites to be three.