Table 2.

Comparison of methods performances on the basis of Si score [19] for the set of n = 34 analytical standards. The delta score between the two methods is calculated as the AF score – the AA score. The blue background color indicates AF score >> AA score (> 0.3). The green background color indicates the AF score > AA score. The red background color indicates AF score < AA score.

Compounds	Pos. Ionization Si Score			Neg. Ionization Si Score
	AA	AF	Δ Score	AA	AF	Δ Score
betaine	0.06	0.58	0.52	0.00	0.00	0.00
valine	0.04	0.35	0.32	0.13	0.57	0.44
leucine	0.05	0.39	0.34	0.10	0.36	0.26
isoleucine	0.07	0.36	0.29	0.10	0.43	0.33
l-phenyllactic acid	0.00	0.00	0.00	0.14	0.10	–0.04
myo-inositol	0.00	0.00	0.00	0.65	0.64	–0.01
fumaric acid	0.00	0.00	0.00	0.42	0.36	–0.06
fructose-6-phosphate	0.23	0.43	0.20	0.39	0.23	–0.16
citric acid	0.00	0.00	0.00	0.00	0.28	0.28
uracil	0.00	0.07	0.07	0.38	0.04	–0.34
nicotinamide-n-oxide	0.12	0.20	0.09	0.55	0.39	–0.16
uridine	0.06	0.20	0.14	0.33	0.43	0.11
5-hydroxy-indole acetic acid	0.00	0.29	0.29	0.43	0.90	0.47
taurine	0.17	0.35	0.18	0.72	0.36	–0.35
mannitol	0.00	0.00	0.00	0.00	0.88	0.88
sorbitol	0.00	0.07	0.07	0.09	0.88	0.80
hydroxy-hippuric acid	0.00	0.00	0.00	0.05	0.20	0.15
tetradecanoic acid	0.00	0.00	0.00	0.00	0.10	0.10
3-indole acetic acid	0.00	0.00	0.00	0.53	0.06	–0.46
hippuric acid	0.01	0.14	0.14	0.67	0.30	–0.37
glycourso-dexoycholic acid	0.07	0.35	0.28	0.28	0.83	0.55
inosine	0.09	0.65	0.56	0.14	0.73	0.58
d-homophenylalanine	0.18	0.73	0.56	0.21	0.74	0.54
l-phenylalanine	0.15	0.70	0.55	0.20	0.74	0.54
l-kynurenine	0.16	0.71	0.55	0.16	0.63	0.47
biotin	0.14	0.66	0.52	0.14	0.65	0.51
d-,l-pantotheic acid	0.00	0.00	0.00	0.29	0.72	0.43
glu-val-phe	0.16	0.38	0.22	0.23	0.70	0.47
l-tryptophan	0.17	0.69	0.52	0.00	0.74	0.74
d,l-pantotheic acid	0.11	0.62	0.51	0.00	0.00	0.00
adipic acid	0.00	0.00	0.00	0.38	0.10	–0.28
cis-4-hydroxy-d-proline	0.16	0.75	0.59	0.57	0.37	–0.19
2-hydroxy-indole acetic acid	0.00	0.67	0.67	0.00	0.00	0.00
deoxyguanosine-5-phosphate	0.00	0.00	0.00	0.44	0.58	0.14