Table 1. Correlation (Pearson’s r) between Metabolites Detected and Quantified in 132 Urine Samples by UPLC–HRMS and DI–nESI–HRMS and Passing–Bablok regression parameters.
Passing–Bablok
regression |
|||
---|---|---|---|
metabolite | Pearson correlation r | slope | intercept |
caffeic acid | 0.58 | 31.8 | 0.2 |
carnitine | 0.96 | 1.2 | 16.6 |
cholate | 0.71 | 19.8 | –0.4 |
citrate | 0.9 | 1.04 | 49.6 |
cotinineb | 0.97 | 1.6 | 0.2 |
creatine | 0.98 | 1.2 | 73.2 |
creatinine | 0.95 | 1.3 | –31.2 |
glutamate | 0.68 | 0.3 | 18.0 |
glycocholate | 0.7 | 24.6 | –0.8 |
hippurate | 0.97 | 0.8 | –23.1 |
homovanillatea | 0.56 | 22.4 | –17.4 |
3-hydroxycinnamatea | 0.39 | 56.3 | 0.1 |
indoxyl sulfate | 0.98 | 0.6 | –0.5 |
isovalerylglycine | 0.78 | 3.2 | 0.7 |
kynureninea | 0.49 | 59.9 | 7.4 |
leucine | 0.69 | 18.8 | 0.6 |
N-acetylneuraminate | 0.88 | 1.2 | 1.1 |
nicotineb | 0.35 | 1.4 | 1.9 |
phenylacetylglutamine | 0.95 | 0.9 | –12.3 |
phenylacetatea | 0.55 | 21.6 | –15.0 |
proline betaine | 0.99 | 1.05 | 3.3 |
propionylcarnitine | 0.89 | 1.03 | 0.2 |
saccharin | 0.98 | 1.06 | –0.01 |
succinate | 0.6 | 6.03 | 4.5 |
tyraminea | 0.34 | 42.03 | 5.1 |
vanillilmandelate | 0.58 | 1.97 | 5.0 |
Metabolites showing weak or moderately weak (r < 0.6) correlation between the two MS methods.
Passing–Bablok regression was done between the samples from smokers only.