. Author manuscript; available in PMC: 2009 Jul 23.

Published in final edited form as: J Am Chem Soc. 2008 Jun 25;130(29):9260–9267. doi: 10.1021/ja800736h

Table 1.

Metal binding constants (Log K_a) and metal selectivity of DTPA, DTPA-BMA and CA1.CD2

Sample	Gd³⁺	Zn²⁺	Ca²⁺	Mg²⁺	Log (K_Gd/K_Zn)	Log (K_Gd/K_Ca)	Log (K_Gd/K_Mg)
DTPA⁴⁰	22.45	18.29	10.75	18.20	4.17	11.70	4.25
DTPA-BMA⁴⁹	16.85	12.04	7.17	na^*	4.81	9.68	na^*
CA1.CD2	12.06	6.72	<2.22	<2.0	5.34	>9.84	>10.06

na: not available.