Design, synthesis, physical and chemical characterisation, and biological interactions of lectin-targeted latex nanoparticles bearing Gd-DTPA chelates: an exploration of magnetic resonance molecular imaging (MRMI).
The physical and chemical parameters involved in the design and synthesis of biospecifically targeted nanoparticulate contrast media for magnetic resonance molecular imaging (MRMI) were explored in this pilot investigation. Latex nanoparticles 100, 400 and 900 nm in diameter were doubly derivatised, first with tomato lectin and then with gadolinium(III)-diethylenetriamine pentaacetic acid (Gd-chelates) to target them to epithelial and endothelial glycocalyceal N-glycans and to generate contrast enhancement in magnetic resonance imaging (MRI). After intravenous injection into mice, human placental cotyledons or human Vena saphena magna, contrasty images of the vascular structures were obtained in 1.5 T MRI with spatial resolution 0.1 mm in the imaging plane and 0.6 mm in the z axis, persisting >60 min and resistant to washing out by buffer rinses. Ultrastructural analysis of the nanoparticles revealed the targeting groups at the nanoparticle surfaces and the distribution of the Gd-chelates within the nanoparticles and enabled counts for use in determining relaxivity. The relaxivity values revealed were extremely high, accounting for the strong MR signals observed. Occasionally, nanoparticles larger than 100 nm were seen in close spatial association with disrupted regions of cell membrane or of collagen fibrils in the extracellular matrix. The data suggest that 100-nm nanoparticles generate adequate contrast for MRMI and cause least disruption to endothelial cell surfaces.
Paschkunova-Martic
Irena
I
Institute of Inorganic Chemistry, University of Vienna, Währingerstrasse 42, 1090 Vienna, Austria.
Kremser
Christian
C
Mistlberger
Klaudia
K
Shcherbakova
Nadezhda
N
Dietrich
Hermann
H
Talasz
Heribert
H
Zou
Yiping
Y
Hugl
Beate
B
Galanski
Mathea Sophia
MS
Sölder
Elisabeth
E
Pfaller
Kristian
K
Höliner
Isabella
I
Buchberger
Wolfgang
W
Keppler
Bernhard
B
Debbage
Paul
P
D000818:Animals; D001808:Blood Vessels / Q000033:anatomy & histology / Q000648:ultrastructure; D003287:Contrast Media / Q000138:chemical synthesis / Q000737:chemistry*; D019786:Gadolinium DTPA / Q000008:administration & dosage / Q000737:chemistry*; D006801:Humans; D066298:In Vitro Techniques; D008279:Magnetic Resonance Imaging / Q000379:methods*; D009682:Magnetic Resonance Spectroscopy; D051379:Mice; D008855:Microscopy, Electron, Scanning; D008863:Microspheres; D037121:Plant Lectins / Q000737:chemistry; D011137:Polystyrenes / Q000737:chemistry
D003287:Contrast Media; D037121:Plant Lectins; D011137:Polystyrenes; C034981:tomato lectin; D019786:Gadolinium DTPA