C. Glogard et al., Synthesis and physicochemical characterisation of new amphiphilic gadolinium DO3A complexes as contrast agents for MRI, J CHEM S P2, 5, 2000, pp. 1047-1052
Citations number
18
Categorie Soggetti
Physical Chemistry/Chemical Physics
Journal title
JOURNAL OF THE CHEMICAL SOCIETY-PERKIN TRANSACTIONS 2
Two approaches were employed in the syntheses of four 1,4,7-tris(carboxymet
hyl)-10-(2-hydroxyalkyl)-1,4,7,10-tetraazacyclododecanes (4) with alkyl cha
in lengths from 4 to 16 carbons. Physicochemical properties, such as critic
al micelle concentration (CMC), micelle size, partition coefficient (P) bet
ween water and octan-1-ol and T-1 relaxivity (r(1)), were investigated for
the corresponding gadolinium (Gd) complexes. The Gd complexes containing th
e shortest alkyl chains (5a and 5b) showed properties typical of water-solu
ble Gd complexes. On the other hand, the long-chained chelates (5c and 5d)
were found to possess amphiphilic properties and to form micelles. The rela
xivities of these amphiphilic complexes were found to be concentration depe
ndent, consistent with the formation of micelles. An unexpectedly high rela
xivity was measured for compound 5d below its CMC. This feature is probably
caused by cluster formation due to low solubility in water.