Fig. 3. (a) One set of serial Fourier-transformed spectra for the CPMG experiments of free ligand (131 ± 6 μM reporter only), non-competition (reporter and 5.7 ± 0.3 μM protein), and competition (reporter, protein, and 42.5 ± 3.8 μM competitor). (b) The fitting results of R₂ relaxation rates for these experiments. The fitted rates for these data sets are 0.556 s⁻¹, 1.43 s⁻¹ and 1.23 s⁻¹ from left to right.