Table 1.
Chemical shifts, spin-lattice relaxation constants (T1), percentage of yield, and hyperpolarized signal enhancement for amino acid mixture data (3.5 mM amino acid)
| Product | Chemical shift, ppm | T1, s | Yield, % | Enhancement |
|---|---|---|---|---|
| N-acetylglycine | 177.13 | 14.7 (0.4) | 91.7 (4.5) | 1,391 (220) |
| N-acetylserine | 177.00 | 10.9 (0.2) | 97.0 (3.0) | 775 (86) |
| N-acetylvaline | 176.79 | 10.0 (0.2) | 93.3 (2.3) | 551 (43) |
| N-acetylleucine | 176.62 | 8.9 (0.6) | 85.0 (4.6) | 412 (70) |
| N-acetylalanine | 176.41 | 14.7 (0.4) | 82.0 (3.6) | 654 (96) |
Data was obtained in triplicate, with averages reported and the corresponding SD indicated in parentheses. Chemical shifts were referenced to acetic anhydride (172.60 ppm).