Table 1.
Summary of the dependence of room-temperature liquid-state 89Y NMR enhancement on the choice of glassing agents and radicals. The NMR enhancements (N = 3) were measured in a 9.4 T magnet at 298 K after dissolution of samples polarized for 9 hours at 1.4 K and 3.35 T. Maximum soluble concentration of Y-DOTA were used in different glassing agents mixed with 50 % water by volume. The error bar in the enhancement is within 5–8 %.
| Glassing matrix | Radical/conc (mM) | YDOTA (M) | Enhancement | % Polarization |
|---|---|---|---|---|
| Pure water | Trityl/15 | 0.48 | 2,200 | 0.35 |
| Glycerol:water | Trityl/15 | 0.28 | 17,700 | 2.79 |
| Glycerol:water | TEMPO/40 | 0.28 | 4,600 | 0.73 |
| Glycerol:water | TEMPO-d16/40 | 0.28 | 5,400 | 0.85 |
| 18-Crown-6:water | Trityl/15 | 0.27 | 20,400 | 3.22 |
| Ethylene glycol:water | Trityl/15 | 0.24 | 12,600 | 1.99 |
| DMSO:water | Trityl/15 | 0.24 | 2,900 | 0.46 |
| 1,3-propanediol:water | Trityl/15 | 0.24 | 18,500 | 2.92 |
| Methanol:water | Trityl/15 | 0.24 | 3,000 | 0.47 |