Can Metal Ion Complexes Be Used As Polarizing Agents for Solution DNP? a Theoretical Discussion

Can metal ion complexes be used as polarizing agents for solution DNP? A theoretical discussion

Claudio Luchinat,* Giacomo Parigi, Enrico Ravera

1CERM, University of Florence, Via Luigi Sacconi 6, 50019, Sesto Fiorentino, Italy and Department of Chemistry “U. Schiff”, University of Florence, via della Lastruccia 3, 50019, Sesto Fiorentino, Italy;

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SUPPLEMENTARY MATERIAL

Materials and Methods

Stock solutions of the aquaions were prepared by dissolving the salts (CuSO4, MnCl2 and GdCl3) at a concentration of 1 M in aqueous solutions containing the corresponding acid (sulfuric and hydrochloric respectively) at a concentration of 1 M. The stock solution was successively diluted in aqueous solutions of the same acid.

The NMRD relaxation profiles were obtained using a fast field cycling relaxometer (Bertini et al., 2005b; Ferrante and Sykora, 2005; Bertini et al., 2005a) by recording the 1H relaxation rates in a range of 0.01 to 40 MHz. Errors in the nuclear relaxation rate measurements were less than 1%.

Proton relaxivity was calculated after subtraction of the relaxation rates of the buffer and division by the paramagnetic ion concentration.

Figure S1. Paramagnetic enhancements to solvent 1H NMRD profiles for Cu2+ aqua ion solutions at 25 (solid symbols) and 40 (empty symbols) °C. The dotted lines represent the best fit curves obtained from the parameters in Table 1 and the SBM theory; the solid lines represent the best fit curves obtained with including the outer-sphere contribution to relaxation in the fit.

Figure S2. Paramagnetic enhancements to solvent 1H NMRD profiles for Mn(H2O)62+ solutions at 25 (solid symbols) and 40 (empty symbols) °C. The dotted lines represent the best fit curves obtained from the parameters in Table 1 and the SBM theory; the solid lines represent the best fit curves obtained with including the outer-sphere contribution to relaxation in the fit.

Figure S3. Paramagnetic enhancements to solvent 1H NMRD profiles for Gd(H2O)83+ solutions at 25 (solid symbols) and 40 (empty symbols) °C. The dotted lines represent the best fit curves obtained from the parameters in Table 1 and the SBM theory; the solid lines represent the best fit curves obtained with including the outer-sphere contribution to relaxation in the fit.

Figure S4. Paramagnetic enhancements to solvent 1H NMRD profiles for VO(H2O)52+ solutions at 25 (solid symbols) and 35 (empty symbols) °C. The dotted lines represent the best fit curves obtained from the parameters in Table 3 and the SBM theory; the solid lines represent the best fit curves obtained with including the outer-sphere contribution to relaxation in the fit.

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