Table 1: Performed experiments with SUC at 7 T and pH 2.9 using buffer B.1.

The hyperpolarization was investigated in three experimental series: In SUC.E1, ECHO was applied and the polarization was measured as a function of the hydrogenation duration by variation of t_delay with a fixed free evolution interval. In SUC.E2, the free evolution interval t_E was varied while t_delay was fixed. To investigate the polarization scheme of the ADAPT sequence, the free evolution interval t_AD,90° was varied with fixed hydrogenation duration t_hydr = 5 s (SUC.E3).

	SOT	Timings / Parameters
SUC.E1	ECHO	tpH2 = 2 s, Variation of tdelay tE = 70.0 ms Setup 1, 90° C
SUC.E2	ECHO	tpH2 = 2 s, tdelay = 3 s Variation of tE Setup 1, 90° C
SUC.E3	ADAPT	tpH2 = 2 s, tbypass = 3 s αx = 90°, nα = 2 Variation of tAD,90° Setup 2, 90° C tMLEV(90°) = 1 ms