Table 1.

Liquid chromatography and mass spectrometry selected parameters.

Mobile phase	Binary system of 0.1% Formic acid in H2O (A) and ACN (B)		ESI source	Positive ESI
				High purity N2 gas Drying gas at 10 L/min with pressure (60 psi)
	0.5 mL/min.
	Elution time: 55 min.
Agilent Zorbax eclipse plus C18Column	Length	150 mm		ESI temperature: 350 °C
	ID	4.6 mm		Capillary voltage: 4000 V
	Particle size	3.5 μm	Modes	Mass scan and MS2
	T	22 ± 1 °C	Collision gas	High purity N2
Gradient elution system	Time in min.	% ACN	Analytes	SPB and its reactive metabolites
	0	5	Mass parameters	Fragmentor voltage (FV): 145 V Amplitude: 1.25 V
	25	75
	40	75
	55	5