Proton relaxation enhancement by means of serum albumin and poly-L-lysine labeled with DTPA-Gd3+: relaxivities as a function of molecular weight and conjugation efficiency.
A series of poly-L-lysine chains, with molecular weight ranging from 3300 up to 102,000 Da, were labeled with DTPA-Gd3+. No significant differences in longitudinal and transversal relaxivity, could be demonstrated as a function of the chain length. The R1 and R2 relaxivities were respectively 2.5 and 5 times superior to those of plain DTPA-Gd3+ (at 2.4 T). Bovine serum albumin was also labeled in a way that a wide (DTPA-Gd3+)/BSA range (3-39) was obtained. The longitudinal relaxivity, of these paramagnetically labeled albumins, increased with increasing (DTPA-Gd3+)/BSA ratios. This effect was most pronounced at very low (DTPA-Gd3+)/BSA ratios.
Spanoghe
M
M
Department of Organic Chemistry, University of Antwerp (RUCA), Belgium.
Lanens
D
D
Dommisse
R
R
Van der Linden
A
A
Alderweireldt
F
F
D019786:Gadolinium DTPA; D007553:Isotope Labeling / Q000379:methods; D009682:Magnetic Resonance Spectroscopy; D008970:Molecular Weight; D009942:Organometallic Compounds; D004369:Pentetic Acid; D011107:Polylysine; D011522:Protons; D012710:Serum Albumin, Bovine
D009942:Organometallic Compounds; D011522:Protons; D011107:Polylysine; D012710:Serum Albumin, Bovine; D004369:Pentetic Acid; D019786:Gadolinium DTPA