Polyaminocarboxylate

Miller SC, Bruenger FW, Kuswik-Rabiega G, et al. 1992. Decorporation of plutonium by oral administration of a partially lipophilic polyaminocarboxylic acid. Health Phys 63(2) 83-85. 

Figure 3 Expanded acyclic polyaminocarboxylates ligands for Galn and In111.

When not complexed, lanthanide ions have a high affinity for bone in vivo because they act as calcium ion mimics. Because the lanthanides undergo hydrolysis above a pH of 4, they readily form radiocolloids when not complexed, and are then taken up by the liver. This bone and liver uptake results in non-specific radiation doses to non-target (normal) tissues and organs and is undesirable.91 The polyaminocarboxylate class of ligands are considered to be the optimal choice for the basis of BFCAs for the+3 metal cations, including the lanthanides. It is essential that the... 

There are several methods used to conjugate DOTA and other polyaminocarboxylate ligands to biomolecules.140,141 The simplest method, commonly used in solid-phase peptide synthesis, is the... 

The oxidation state +3 of bismuth is of primary interest for radiotherapy applications. As such, various polyaminocarboxylate ligands have been investigated as chelates for 212Bi and 213Bi. 

The Ru(IV)/Ru(III) redox potential is 0.78 V, so that Ru(III) or even Ru(II) species may be present in vivo. Indeed, the related Ru(III) complex 32 is also active (171), and the pendant arms in these octahedral polyaminocarboxylate complexes increase the rate of substitution reactions. Complex 32 binds rapidly to the blood proteins albumin and transferrin (172), and the ruthenium ion appears to remain in the... 

Fig. 2. Plot of the relaxivity (20 MHz an 25°C) for monoaquo polyaminocarboxylate Gd(III) complexes (Charts 2 and 3) versus molecular weight. The correlation coefficient R is 0.988.

The mean residence lifetime of coordinated water protons represents one of the most important parameters that control the relaxivity of Gd(III) complexes 18). For several years it had been assumed that xm for the low molecular weight polyaminocarboxylate Gd(III) complexes was of the order of a few ns, as found for the octaaqua ion. In 1993, Merbach reported the first direct measurement of the water exchange rate for [GdDTPA(H20)] and [GdD0TA(H20)] and found that for these CAs the rate of water exchange was nearly three orders of magnitude lower than that for [Gd(H20)8] 49). 

Reactions of iron-polyaminocarboxylates with nitric oxide have already been covered, in Section 5.4.3.8 bi- and polynuclear complexes containing polyaminocarboxylate ligands will be found in Section 5.4.5.4 below. 

Extensive efforts have been made to establish and rationalize the kinetics of dioxygen oxidation of iron(II) polyaminocarboxylate complexesThe kinetics of dioxygen oxidation of iron(II) complexes of 1,2- and of 1,3-propylenetetraacetate show the influence of steric factors on these electron transfer reactions7 " ... 

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