Proton relaxation enhancement by means of serum albumin and poly- l-lysine labeled with DTPA-Gd 3+: Relaxivities as a function of molecular weight and conjugation efficiency

• Published in: Magnetic resonance imaging Vol. 10; no. 6; pp. 913 - 917
• Main Authors: Spanoghe, M., Lanens, D., Dommisse, R., Van der Linden, A., Alderweireldt, F.
• Format: Journal Article
• Language: English
• Published: Elsevier Inc 1992
• Subjects: (DTPA-Gd)-labeling; Macromolecular contrast agents; Magnetic resonance imaging; Magnetic resonance imaging; (DTPA-Gd)-labeling; Macromolecular contrast agents
• ISSN: 0730-725X; 1873-5894
• DOI: 10.1016/0730-725X(92)90445-6

A series of poly- l-lysine chains, with molecular weight ranging from 3300 up to 102,000 Da, were labeled with DTPA-Gd 3+. No significant differences in longitudinal and transversal relaxivity, could be demonstrated as a function of the chain length. The R 1 and R 2 relaxivities were respectively 2.5 and 5 times superior to those of plain DTPA-Gd 3+ (at 2.4 T). Bovine serum albumin was also labeled in a way that a wide (DTPA-Gd 3+) BSA range (3–39) was obtained. The longitudinal relaxivity, of these paramagnetically labeled albumins, increased with increasing (DTPA-Gd 3+) BSA ratios. This effect was most pronounced at very low (DTPA-Gd 3+) BSA ratios.