Table 1.

Relaxometric Properties of Complexes 1–4 at pH 7.4 and 37 °C

	Relaxivity (mM−1s−1)a		q	τm (ns)c
	60 MHz (1.5 T)	600 MHz (14.1 T)b
(Gd(III)-DOTA-Arg8) 1	6.8	3.50	1.0	916
(Gd(III)-DTPA-Arg8) 2	7.8	3.45	1.2	1105
(Gd(III)-DOTA-SS-Arg8) 3	6.9	3.52	0.9	840
(Gd(III)-DTPA-SS-Arg8) 4	7.4	3.46	1.1	1327
Gd(III)-DOTA	3.2	2.12	1.2d	243e
Gd(III)-DTPA	3.8	2.09	1.2d	303e

^aMeasured in 100 mM phosphate buffer

^bmeasured at ambient temperature (~ 25 °C)

^ccalculated at 25 °C

^ddata from ref (51)

^edata from ref (52).