Table 1.
Values for longitudinal relaxation (T1) of water at 288K and 298K and varying buffer conditions measured by the saturation-recovery method, unless otherwise indicated. The reference sample was described as “ordinary water”, where the oxygen has been removed by flushing the sample with helium. A sample (3 or 1 mm tube) of deionized H2O/D2O 95:5, degassed, was used for comparison. The Sucrose standard sample (5mm tube) contains 2 mM sucrose, 0.5 mM 4,4-dimethyl-4-silapentane-1-sulfonic acid (DSS), 2 mM sodium azide (NaN3) in H2O/D2O 9:1. The DNA sample (3 or 1 mm tube) contained the above described NMR buffer, with or without 10 mM NH3, respectively. Additional tests showed consistent T1-values regardless of the tube diameter used, including 5 mm and 1.7 mm tubes.
| T1 [sec], 288K | T1 [sec], 298K | |
|---|---|---|
| Reference (Simpson and Carr 1958) | 2.55 | 3.37 |
| Water sample (H2O/D2O 95:5), 3mm | 2.64± 0.01 | 3.53 ± 0.01 |
| Water sample (H2O/D2O 95:5), 1mm | 2.65± 0.02 | 3.56 ± 0.01 |
| Water sample (H2O/D2O 95:5), 1mm* | 2.71 ± 0.01 | 3.55 ± 0.01 |
| Sucrose standard sample | 2.66 ± 0.01 | 3.46 ± 0.09 |
| DNA Sample in NMR buffer, 3mm | 2.61 ± 0.03 | 3.48 ± 0.01 |
| DNA Sample in NMR buffer, 1mm | 2.67± 0.07 | 3.46 ± 0.03 |
| DNA Sample in NMR buffer, 1mm* | 2.73± 0.01 | 3.49 ± 0.01 |
| DNA Sample in NMR buffer and 10 mM NH3 | 2.50 ± 0.05 | 3.14 ± 0.01 |
Measured by the standard inversion recovery method