Stereospecific binding of MRI contrast agents to human serum albumin: the case of Gd-(S)-EOB-DTPA (Eovist) and its (R) isomer.
The water proton relaxation rate enhancement of the hepatospecific Gd-(S)-EOB-DTPA (Eovist) and of its (R) isomer in aqueous solutions free of protein, in serum and in 4% human serum albumin solution, are compared. In the absence of proteins, both compounds exhibit, as expected, the same proton relaxivity, as measured by the nuclear magnetic relaxation dispersion (NMRD) profiles. In serum and albumin solution, non-covalent binding of the paramagnetic complexes to macromolecules is observed. Both isomers are likely to bind to the same site of human serum albumin, but the affinity of the (S) isomer is larger than for the (R) isomer.
Vander Elst
L
L
Department of Organic Chemistry, University of Mons-Hainaut, Belgium.
Chapelle
F
F
Laurent
S
S
Muller
R N
RN
D003287:Contrast Media / Q000737:chemistry* / Q000378:metabolism; D019786:Gadolinium DTPA; D006801:Humans; D008279:Magnetic Resonance Imaging / Q000379:methods*; D009942:Organometallic Compounds / Q000737:chemistry / Q000378:metabolism; D011485:Protein Binding; D012709:Serum Albumin / Q000737:chemistry* / Q000378:metabolism; D013237:Stereoisomerism; D014867:Water
D003287:Contrast Media; D009942:Organometallic Compounds; D012709:Serum Albumin; C073590:gadolinium ethoxybenzyl DTPA; D014867:Water; D019786:Gadolinium DTPA