Table 1. MS/MS conditions for choline-containing compounds.
A. SRM parameters and the retention time
| Compound | Category | Q1 (m/z) |
Q3 (m/z) |
DP (V) |
EP (V) |
CE (V) |
CXP (V) |
Retention time (min) |
|---|---|---|---|---|---|---|---|---|
| Choline | Analyte | 104 | 58 | 40 | 10 | 39 | 8 | 4.65 |
| Acetylcholine | Analyte | 146 | 87 | 20 | 10 | 19 | 4 | 4.23 |
| Betaine | Analyte | 118 | 58 | 20 | 10 | 37 | 12 | 4.89 |
| Phosphocholine | Analyte | 184 | 125 | 200 | 10 | 25 | 14 | 6.11 |
| Glycerophosphocholine | Analyte | 258 | 104 | 20 | 10 | 23 | 12 | 5.84 |
| LPC (sn-1, 16:0) | Analyte | 496 | 184 | 160 | 6 | 31 | 10 | 3.77 |
| LSM (d18:1/18:0) | Analyte | 465 | 184 | 140 | 4 | 29 | 8 | 4.69 |
| Choline-2H9 | IS | 113 | 66 | 30 | 6 | 35 | 12 | 4.65 |
| Betaine-2H11 | IS | 129 | 68 | 36 | 8 | 23 | 14 | 4.89 |
| Phosphocholine-2H9 | IS | 193 | 95 | 20 | 10 | 23 | 6 | 6.10 |
| Glycerophosphocholine-2H9 | IS | 267 | 113 | 20 | 8 | 23 | 26 | 5.84 |
| LSM (d18:1/17:0) | IS | 451 | 184 | 120 | 6 | 27 | 12 | 4.66 |
CE, collision energy; CXP, cell exit potential; DP, declustering potential; IS, internal standard; LPC, lysophosphatidylcholine; LSM, lysosphingomyelin; MS/MS, tandem mass spectrometry; SRM, selected reaction monitoring.