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Controlled intracellular self-assembly of gadolinium nanoparticles as smart molecular MR contrast agents.

ABSTRACT: Herein we developed a new "smart" Gd-based MR contrast agent (i.e., 1) which is susceptive to furin, a protease overexpressed in tumor. Under the action of furin, 1 condenses to form dimers (1-Ds) and the latter self-assemble into gadolinium nanparticles (Gd-NPs). Relaxivity of 1-D is more than 2 folds of those of 1 and magnevist at 1.5?T, and 1.4 folds of that of 1 at 3?T. Intracellular condensation of 1 in furin-overexpressed MDA-MB-468 cells was proven with direct two-photon laser microscopy (TPLM) fluorescence imaging of the cells incubated with the europium analog of 1 (i.e., 2). Intracellular Gd-NPs of 1 were uncovered and characterized for the first time. MRI of MDA-MB-468 tumors showed that 1 has enhanced MR contrast within the tumors than that of its scrambled control 1-Scr.

SUBMITTER: Cao CY

PROVIDER: S-EPMC3535584 | biostudies-literature | 2013

REPOSITORIES: biostudies-literature

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Controlled intracellular self-assembly of gadolinium nanoparticles as smart molecular MR contrast agents.

Cao Chun-Yan CY Shen Ying-Ying YY Wang Jian-Dong JD Li Li L Liang Gao-Lin GL

Scientific reports 20130103

Herein we developed a new "smart" Gd-based MR contrast agent (i.e., 1) which is susceptive to furin, a protease overexpressed in tumor. Under the action of furin, 1 condenses to form dimers (1-Ds) and the latter self-assemble into gadolinium nanparticles (Gd-NPs). Relaxivity of 1-D is more than 2 folds of those of 1 and magnevist at 1.5 T, and 1.4 folds of that of 1 at 3 T. Intracellular condensation of 1 in furin-overexpressed MDA-MB-468 cells was proven with direct two-photon laser microscopy ...[more]

PMID: 23289066

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Controlled intracellular self-assembly of gadolinium nanoparticles as smart molecular MR contrast agents.

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Controlled intracellular self-assembly of gadolinium nanoparticles as smart molecular MR contrast agents.

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