Figure 3.

(A) Typical R_2.5 and R_1.95 curves extracted using the two-peak PLOF method. (B) The corresponding fitting results (Z_back and Z) of one Z-spectrum collected on a WT mouse (R² =0.9974) with 1 μT saturation power. The frequency range between 1.3 and 3.4 ppm was utilized for the fitting and three sections, i.e. 1.3–1.7 ppm, 2.25–2.35 ppm and 2.83–3.4 ppm, were selected for the background fitting. (C) The observed CEST signals (ΔZ) at 3.6 ppm, 2.5 ppm and 1.95 ppm as a function of saturation power. (D) The extracted $R_{2.5}^{max}$ and $R_{1.95}^{max}$ as a function of saturation power.