Table 3.
Potential biomarkers confirmed using tandem mass spectrometry. List of metabolites that showed significant alterations in early vs late stages of EC. (m/z = mass/charge; ppm = parts per million; RT = retention time; p-v = p-value; FC = fold change; FDR = false discovery rate; AUC = area under the curve).
| Metabolite | m/z | Mass error (ppm) | RT (min) | Early vs late EC stages | FC (early/late) | p-value | FDR | AUC | Formula | Ionization mode | Column | Major CID fragments |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Arachidonic Acid | 303.2325 | 1 | 6.8246 | ↓ | 0.1402 | 6.24E-03 | 8.74E-03 | 0.778 | C20H32O2 | Negative | C18_BEH | 259.25, 216.99, 205.19 |
| PC(16:0/20:5) | 780.5545 | 0 | 8.8476 | ↓ | 0.3311 | 3.13E-03 | 5.48E-03 | 0.750 | C44H78NO8P | Positive | C18_BEH | 88.11, 184.07, 255.21, 393.24 |
| PC(16:0/22:6) | 806.5709 | 1 | 9.0460 | ↑ | 3.0814 | 7.86E-04 | 5.48E-03 | 0.807 | C46H80NO8P | Positive | C18_BEH | 184.07, 267.21, 478.32, 550.32, 623.50 |
| PE(16:0/22:6) | 762.5106 | 3 | 9.0937 | ↑ | 2.0349 | 8.36E-03 | 9.75E-03 | 0.752 | C43H74NO8P | Negative | C18_BEH | 140.01, 255.23, 283.24, 327.23, 452.27 |
| PE(18:1/22:6) | 788.5258 | 2 | 9.1145 | ↑ | 15.2799 | 2.2E-02 | 2.20E-02 | 0.676 | C45H76NO8P | Negative | CSH and C18_BEH | 78.95 140.01, 152.99, 281.24, 283.26, 327.23, 460.26, 478.29, 506.26 |
| PE(22:6/P-18:1) | 772.5278 | 1 | 9.3001 | ↓ | 0.4065 | 1.86E-03 | 5.48E-03 | 0.800 | C45H76NO7P | Negative | CSH and C18_BEH | 140.01, 283.24, 327.23, 444.28, 462.29 |
| UDP-N-acetyl-D-galactosamine | 606.0739 | 0 | 0.5454 | ↓ | 0.3765 | 2.97E-02 | 5.48E-03 | 0.688 | C17H27N3O17P2 | Negative | C18_BEH | 111.0222, 158.92, 176.93, 282.04, 362.00, 385.00 |