Table 1. Relaxivities of Gd₄-TESMA and Gd-TESMA at 20 and 125 MHz (298 K, 3.8 mM HEPES, 150 mM NaCl, pH 7.2).

compound	r1mM (mM–1 s–1) at 20 MHz	r1mM (mM–1 s–1) at 125 MHz
Gd4-TESMA
per molecule	34.0 ± 0.8	32.4 ± 0.8
per Gd(III)	8.5 ± 0.2	8.1 ± 0.2
Gd-TESMA (1 mM)	10.0 ± 0.3	10.4 ± 0.3