Table 1.

Settings of the HPLC program.

Time (minutes)	Pump 1 (main column (MC))			Pumps 2 and 3 (trapping column (TC))
	%B	Flow (µL/min)	Comments	%B	Flow (µL/min)	Flow pump 5 (H2O + 0.1% HCOOH) (µL/min)	Switching valve
0	35	500	Start MS and pumps	50	300	800	TC → waste, MC → MS (loading)
0.5	35		Start gradient	50	300	800	TC → MC → MS (eluting)
0.6	↓			50	20	20
1	97.5
2	97.5						TC → waste, MC → MS
2.5	35			50	300	800	Reequilibration