Paramagnetic Silica-Coated Nanocrystals as an Advanced MRI Contrast Agent
| Autor: | Joe W. Gray, John Kurhanewicz, Robert Maxwell, Thomas F. Budinger, Daniele Gerion, Erick Ramon, Robert Bok, Fanqing Frank Chen, Marc A. Shuman, Julie L. Herberg, Erica Gjersing |
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| Rok vydání: | 2007 |
| Předmět: |
Materials science
MRI contrast agent Gadolinium Analytical chemistry chemistry.chemical_element Nanoparticle Surfaces Coatings and Films Electronic Optical and Magnetic Materials Paramagnetism chemistry.chemical_compound General Energy chemistry Ionic strength Quantum dot Colloidal gold DOTA Physical and Theoretical Chemistry |
| Zdroj: | The Journal of Physical Chemistry C. 111:12542-12551 |
| ISSN: | 1932-7455 1932-7447 |
| DOI: | 10.1021/jp074072p |
| Popis: | We present a robust and general method for embedding nanoparticles, such as quantum dots (QD) or colloidal gold (Au) nanocrystals, into a highly water-soluble thin silica shell doped with paramagnetic gadolinium (Gd3+) ions without negatively impacting the optical properties of the QD or Au nanoparticle cores. The ultrathin silica shell has been covalently linked to Gd3+ ions chelator, tetraazacyclododecanetetraacetic acid (DOTA). The resulting complex has a diameter of 8 to 15 nm and is soluble in high ionic strength buffers at pH values ranging from approximately 4 to 11. For this system, nanoparticle concentrations exceed 50 μM, while most other nanoparticles might aggregate. In magnetic resonance imaging (MRI) experiments at clinical magnetic field strengths of 1.4 T (1H resonance frequency of 60 MHz), the gadolinium−DOTA (Gd−DOTA) attached to SiO2-coated QDs has a spin−lattice (T1) particle relaxivity (r1) and a spin−spin (T2) particle relaxivity (r2) of 1019 ± 19 mM-1s-1 and 2438 ± 46 mM-1 s-1, resp... |
| Databáze: | OpenAIRE |
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