TY - JOUR
T1 - Contrast agents for magnetic resonance angiographic applications
T2 - 1H and 17O NMR relaxometric investigations on two gadolinium(III) DTPA-like chelates endowed with high binding affinity to human serum albumin
AU - Aime, Silvio
AU - Chiaussa, Monica
AU - Digilio, Giuseppe
AU - Gianolio, Eliana
AU - Terreno, Enzo
N1 - Funding Information:
Fig. 8 Plot of the relaxivity values (r1b) for Gd(III) complexes/ HSA adducts versus temperature at pH 5.5 and pH 8.5: A MS-325; B [Gd(BOM)3DTPA(H2O)]2–. The profiles of the HSA-bound complexes were calculated from solutions containing 0.1 mM of the complex and a large excess (1.7 mM) of HSA Acknowledgements We thank Dr. Pierfrancesco Morosini and Mr. Andrea Beltrami (Bracco S.p.a., Milan, Italy) for the syntheses of the samples of MS-325 and [Gd(BOM)3DTPA (H2O)]2– which were used in this study. We gratefully acknowledge the stimulating discussions with Drs. P.L. Anelli, L. Calabi, and F. Uggeri. Financial support from Bracco S.p.a., MURST, and CNR (Biotechnology Program L 95/95) is also gratefully acknowledged.
PY - 1999/12
Y1 - 1999/12
N2 - The relaxometric properties of two Gd(III) DTPA-like complexes (DTPA = diethylenetriamine-N,N',N,N'-pentaacetic acid) bearing different substituents for binding to human serum albumin (HSA) are compared. In spite of the structural differences of the recognition synthon and of the residual electric charge, the two chelates display an analogous binding affinity for the serum protein. Upon formation of the adducts with HSA, the exchange rates of the coordinated water appear slowed down by an amount corresponding to ca. 50% of the rates found for the free complexes. The relaxivity of [Gd(BOM)3DTPA (H2O)]2- is significantly higher than that of MS-325 either in the free complex or in the macromolecular adduct. Finally, the effect of pH on the stability of the HSA adducts and on the values of their relaxivities has been investigated.
AB - The relaxometric properties of two Gd(III) DTPA-like complexes (DTPA = diethylenetriamine-N,N',N,N'-pentaacetic acid) bearing different substituents for binding to human serum albumin (HSA) are compared. In spite of the structural differences of the recognition synthon and of the residual electric charge, the two chelates display an analogous binding affinity for the serum protein. Upon formation of the adducts with HSA, the exchange rates of the coordinated water appear slowed down by an amount corresponding to ca. 50% of the rates found for the free complexes. The relaxivity of [Gd(BOM)3DTPA (H2O)]2- is significantly higher than that of MS-325 either in the free complex or in the macromolecular adduct. Finally, the effect of pH on the stability of the HSA adducts and on the values of their relaxivities has been investigated.
KW - Contrast agents
KW - Gadolinium(III) complexes
KW - Human serum albumin
KW - Magnetic resonance imaging
KW - Proton relaxation enhancement
UR - http://www.scopus.com/inward/record.url?scp=0032714162&partnerID=8YFLogxK
U2 - 10.1007/s007750050349
DO - 10.1007/s007750050349
M3 - Article
SN - 0949-8257
VL - 4
SP - 766
EP - 774
JO - Journal of Biological Inorganic Chemistry
JF - Journal of Biological Inorganic Chemistry
IS - 6
ER -