A Simple and Rapid LC-MS/MS Method for Quantification of Total Daidzein, Genistein, and Equol in Human Urine

Table 1

Summary of the monitored protonated ions and the optimised MS operating parameters of the analytes.

Analytes	(M-H)^− (m/z)	Precursor ion (Q1)	Product ion (Q3)	DP (volts)	CE (volts)	CXP (volts)
Taxifolin (IS)	303	303	125	−80	−30	−9
Equol	241	241	121	−75	−20	−7
Genistein	269	269	133	−90	−42	−9
Daidzein	253	253	91	−95	−50	−13
Equol-glucuronide	417	417	241	−75	−20	−7
Equol-diglucuronide	593	593	241	−75	−20	−7
Equol-sulfate	321	321	241	−75	−20	−7
Equol-disulfate	401	401	241	−75	−20	−7
Genistein-glucuronide	445	445	269	−90	−42	−9
Genistein-diglucuronide	621	621	269	−90	−42	−9
Genistein-sulfate	349	349	269	−90	−42	−9
Genistein-disulfate	429	429	269	−90	−42	−9
Daidzein-glucuronide	429	429	253	−95	−50	−13
Daidzein-diglucuronide	605	605	253	−95	−50	−13
Daidzein-sulfate	333	333	253	−95	−50	−13
Daidzein-disulfate	413	413	253	−95	−50	−13
Daidzein-sulfoglucuronide	509	509	253	−95	−50	−13
Genistein-sulfoglucuronide	525	525	269	−90	−42	−9
Equol-sulfoglucuronide	497	497	241	−75	−20	−7