Table 2. Calibration curves for choline-related compounds.
| Analyte | IS | Slope | Intercept | Correlation coefficient | Weighting | LLOQ (ng/mL) |
ULOQ (ng/mL) |
|---|---|---|---|---|---|---|---|
| Choline | Choline-2H9 | 0.27984 | 2.46808 | 0.99575 | 1/x2 | 1 | 10,000 |
| Acetylcholine | Choline-2H9 | 0.99342 | −0.04749 | 0.99779 | 1/x2 | 3 | 10,000 |
| Betaine | Betaine-2H11 | 0.0262 | 0.61983 | 0.99681 | 1/x | 5 | 10,000 |
| Phosphocholine | Phosphocholine-2H9 | 0.00095 | 0.11448 | 0.99541 | 1/x2 | 10 | 10,000 |
| Glycerophosphocholine | Glycerophosphocholine-2H9 | 0.00535 | 0.00073 | 0.99708 | 1/x2 | 2 | 10,000 |
| LPC (sn-1, 16:0) | Glycerophosphocholine-2H9 | 0.00172 | 0.03764 | 0.98973 | 1/x2 | 30 | 10,000 |
| LSM (d18:1/18:0) | LSM (d18:1/17:0) | 0.0087 | −0.01043 | 0.99487 | 1/x2 | 2 | 5,000 |
IS, internal standard; LLOQ, lower limit of quantification; LPC, lysophosphatidylcholine; LSM, lysosphingomyelin; ULOQ, upper limit of quantification.