Adjusted parameters of the proposed LC-MS/MS methodology.

LC parameters			MS/MS parameters
HPLC	Agilent 1200		Mass spectrometer	Agilent 6410 QqQ
Gradient mobile phase	A: 10 mM NH4COOH in H2O		Ionization source	Positive ESI
	B: ACN			Drying gas: N2 gas
	Flow rate: 0.4 mL min−1			Flow rate (12 L min−1)
	Run time: 75 min			Pressure (60 psi)
Agilent eclipse plus C18 column	Length	150 mm		ESI temperature: 350 °C
	Internal diameter	2.1 mm		Capillary voltage: 4000 V
	Particle size	3.5 µm	Collision gas	High purity N2
	Temperature:	22 ± 1 °C	Modes	Mass scan and product ion (PI)
Gradient system	Time	% B	Analyte	DCB and its reactive metabolites
	0	5
	5	5	Mass parameters	Fragmentor voltage: 140 V
	40	60
	70	90
	75	5		Collision energy of 20 eV