Surface functionalization of magnetoliposomes in view of improving iron oxide-based magnetic resonance imaging contrast agents: anchoring of gadolinium ions to a lipophilic chelate.
Small unilamellar phospholipid vesicles containing the phosphatidylethanolamine-diethylene triamine pentaacetic acid (PE-DTPA) conjugate as one of the building stones were constructed. The ability of these colloids to complex gadolinium(III) ions at the surface of both the inner and outer bilayer shells was verified using a colorimetric method with Arsenazo III as a dye indicator. On incubation of these functionalized vesicles with magnetoliposomes (MLs, nanometer-sized magnetite cores encapsulated in a phospholipid bilayer), PE-DTPA percolates into the ML coat. The PE-DTPA content could be fine-tuned by varying the conjugate concentration in the donor vesicles. In the experimental conditions applied, up to 500 Gd(3+) ions were immobilized per ML colloid. The resulting ML-Gd(3+) complexes might have great potential, for example, as a novel magnetic resonance imaging contrast agent.
De Cuyper
Marcel
M
Interdisciplinary Research Centre, Katholieke Universiteit Leuven-Campus Kortrijk, B-8500 Kortrijk, Belgium. marcel.decuyper@kuleuven-kortrijk.be
Soenen
Stefaan J H
SJ
Coenegrachts
Kenneth
K
Beek
Léon Ter
LT
D001150:Arsenazo III / Q000737:chemistry; D003287:Contrast Media / Q000737:chemistry*; D005290:Ferric Compounds / Q000737:chemistry*; D019786:Gadolinium DTPA / Q000737:chemistry*; D007700:Kinetics; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008280:Magnetics; D053768:Metal Nanoparticles / Q000737:chemistry; D004369:Pentetic Acid / Q000737:chemistry; D010714:Phosphatidylethanolamines / Q000737:chemistry*; D053835:Unilamellar Liposomes / Q000737:chemistry*
D003287:Contrast Media; D005290:Ferric Compounds; D010714:Phosphatidylethanolamines; D053835:Unilamellar Liposomes; C082531:gadolinium phosphatidylethanolamine-DTPA; D001150:Arsenazo III; C000499:ferric oxide; D004369:Pentetic Acid; D019786:Gadolinium DTPA; C018525:1,2-dimyristoylphosphatidylethanolamine