Table 1. Spectroscopic DNP properties of CoQ0-and PQQ-mediated AFR, 14N-CmP, Oxo63, and FMNH.
| Radical conc. (c) (μ M) | Peak location (MHz) | Half width (MHz) | Intensity (OFF): I0 (a.u.) | Intensity (ON): IZ (a.u.) | Enhancement: ε | Ratio: ε/c (/μ M) | |
|---|---|---|---|---|---|---|---|
| CoQ0-med. AFR | 25~10 (17A) | 198.7 (236.2**) | |||||
| Left peak | 525.0 | 2.0 (1.8*) | 844.4 (934.8**) | 4.2 (4.0**) | 0.2~0.4 (0.25B) | ||
| Right peak | 520.0 | 1.8 (1.9*) | 896.8 (911.3**) | 4.5 (3.9**) | 0.2~0.5 (0.27D) | ||
| 14N-CmP | 150 | 206.1 | |||||
| Center peak | 526.5 | 3.8 | 907.5 | 4.4 | 0.03 | ||
| Oxo63 | 60 | 177.9 | |||||
| Center peak | 522.0 | 1.6 | 831.2 | 4.7 | 0.08 | ||
| FMNH | 120 | – | – | 228.1 | 835.7 | 3.7 | 0.03 |
| PQQ-med. AFR | 11~9 (10F) | 277.5 (253.4) | |||||
| Left peak | 525.0 | 2.0 | 698.2 (648.4) | 2.5 (2.6) | 0.2~0.3 (0.25G) | ||
| Right peak | 520.0 | 2.0 | 642.2 (645.2) | 2.3 (2.5) | 0.2~0.3 (0.23H) |
The spans of the radical concentrations and the values of ε/c for the CoQ0- and PQQ- mediated AFR were obtained with the doublet AFR spectra recorded at 30 and 105 s after the mixing (A, Fvalues were obtained with the the doublet AFR spectra recorded at 60 s). B, D, G, HValues are calculated with A, Fvalues, respectively. Values with no asterisk, *values, and **values of mean (n = 3) were obtained with Figs 2(b) and 1(d,f), respectively. Values for FMNH are obtained with Figure S-7d (DNP OFF and 525 MHz). Values for the PQQ-mediated AFR are from Table S-1.