Table 2.

Examples for Eliminating False Positive MS/MS Compound Annotations in Human BioIVT Plasma by Predicting HILIC Retention Time Using Retip

false positive MS/MS spectrum	MS/MS score	retention time obsd (min)	retention time predicted (min)	Δ (retention time) (obsd – pred) (min)	true retention time HILIC library (min)
carnitine	981	9.6	7.6	2.0	7.7
nicotinamide	758	7.5	2.6	4.9	1.8
pipecolic acid	876	9.5	7.1	2.4	7.7
indole-3-carboxylic acid	656	7.9	1.8	6.1	1.4
amantadine	626	1.4	4.9	3.5	4.8
mepirizole	735	6.0	1.1	4.9	1.0
N-methylproline	878	9.6	7.3	2.3	7.0
phenethylamine	761	1.5	5.0	3.5	4.7