TABLE 1.
LC-MS/MS parameters for quinoxaline quantitation
| Quinoxaline and letter assignment (see Fig. 2) | Retention time | Precursor ion |
Product ion 1a |
Product ion 2b |
Product ion 3b |
|||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| m/z | DPc | m/z | CEd | CXPe | m/z | CE | CXP | m/z | CE | CXP | ||
| min | amuf | V | amu | eV | V | amu | eV | V | amu | eV | V | |
| 2,3-DKG (a) | 9.5 | 265.1 | 40 | 185.1 | 23.0 | 11.0 | 221.1 | 17.0 | 17.0 | 161.0 | 27.0 | 11.0 |
| Glucosone (b) | 9.9 | 251.1 | 55 | 173.1 | 24.0 | 16.0 | 161.1 | 30.0 | 13.0 | 233.2 | 19.0 | 16.0 |
| Oxalic acid (c) | 10.5 | 162.9 | 70 | 90.1 | 42.0 | 15.0 | 145.1 | 25.0 | 10.0 | 117.1 | 31.0 | 7.0 |
| Pentosone (d) | 11.2 | 221.1 | 50 | 173.1 | 22.0 | 14.0 | 161.0 | 27.0 | 13.0 | 132.1 | 45.0 | 10.0 |
| 1-DG (e) | 11.9 | 235.2 | 55 | 175.1 | 28.0 | 12.0 | 187.1 | 27.0 | 11.0 | 217.2 | 18.0 | 16.0 |
| DHA (f) | 12.0 | 247.1 | 55 | 229.0 | 18.0 | 20.0 | 185.3 | 20.0 | 15.0 | 171.1 | 33.0 | 10.0 |
| 3-DG (g) | 13.9 | 235.2 | 55 | 199.1 | 24.0 | 17.0 | 145.0 | 31.0 | 9.0 | 157.1 | 12.0 | 30.0 |
| Threosone (h) | 14.0 | 191.2 | 45 | 173.1 | 17.5 | 14.0 | 144.1 | 37.0 | 11.0 | 161.2 | 24.0 | 12.0 |
| 1-DP (i) | 16.8 | 205.1 | 50 | 187.1 | 21.0 | 14.0 | 145.1 | 27.0 | 12.0 | 169.2 | 30.0 | 11.0 |
| Glyoxylic acid (j) | 17.1 | 147.1 | 65 | 129.0 | 26.5 | 9.0 | 119.1 | 30.0 | 10.0 | 102.1 | 39.0 | 8.5 |
| 3-DP (k) | 17.1 | 205.1 | 50 | 187.2 | 19.5 | 10.0 | 158.1 | 34.0 | 14.0 | 174.1 | 32.5 | 13.0 |
| Lederer's glucosone | 18.4 | 363.3 | 65 | 187.1 | 27.0 | 16.0 | 159.1 | 29.0 | 10.0 | 219.1 | 24.0 | 12.0 |
| 3-DT (l) | 19.2 | 175.1 | 55 | 157.2 | 24.0 | 10.0 | 129.2 | 35.0 | 9.0 | 145.0 | 25.5 | 10.0 |
| DHA precursor (m) | 19.5 | 355.3 | 52 | 109.2 | 19.0 | 8.0 | 247.2 | 15.0 | 16.0 | 337.2 | 15.0 | 12.0 |
| Pyruvic acid (n) | 19.5 | 160.9 | 60 | 133.1 | 28.0 | 10.0 | 91.9 | 40.0 | 7.0 | 64.9 | 54.0 | 11.0 |
| Pyruvic acid-13C2 | 19.5 | 163.1 | 60 | 134.0 | 28.0 | 10.0 | 92.1 | 40.0 | 7.0 | 64.9 | 54.0 | 11.0 |
| 1-DT (o) | 19.6 | 175.1 | 45 | 157.1 | 22.0 | 7.0 | 156.1 | 35.0 | 15.0 | 89.1 | 55.0 | 5.0 |
| 3,4-DDP (p) | 20.5 | 189.1 | 55 | 171.2 | 25.0 | 15.0 | 145.1 | 25.0 | 11.0 | 102.1 | 52.0 | 16.0 |
| GO (q) | 20.9 | 131.1 | 32 | 77.0 | 40.0 | 6.0 | 104.0 | 30.0 | 8.0 | |||
| MGO (r) | 22.3 | 145.0 | 50 | 77.0 | 41.0 | 5.0 | 118.1 | 30.5 | 7.0 | 65.0 | 45.0 | 5.0 |
a MRM transition used for quantitation (quantifier).
b MRM transition used for confirmation (qualifier).
c DP, declustering potential.
d CE, collision energy.
e CXP, collision cell exit potential.
f amu, atomic mass units.