Table 1.

Retention time and MRM transitions of polyphenols.

Polyphenols	Retention Time (min)	Molecular Weight	Transition Time 1 (m/z)	Transition Time 2 (m/z)
Salicylic acid	8.17	138	139 → 95	139 → 77.1
Cinnamic acid	19.22	148	149 → 131	149 → 103
Benzoic acid	15.02	122	123 → 79.1	123 → 77.1
4-hydroxybenzoic acid	15.61	138	139 → 65	139 → 39