Water-soluble superparamagnetic magnetite nanoparticles with biocompatible coating for enhanced magnetic resonance imaging.
ACS Nano
; 5(8): 6315-24, 2011 Aug 23.
Article
em En
| MEDLINE
| ID: mdl-21790153
ABSTRACT
Ultrasmall superparamagnetic Fe(3)O(4) nanoparticles (USIRONs) were synthesized by a novel, easily scalable chemical reduction of colloidal iron hydroxide under hydrothermal conditions. The average crystallite size (5.1 ± 0.5 nm) and good crystallinity of the samples were supported by HR-TEM analysis and the saturation magnetization value (47 emu g(-1)). Vitamin C, used as a chemical reducing agent, also served as a capping agent in the oxidized form (dehydroascorbic acid, DHAA) to impart nanoparticles with exceptional solubility and stability in water, PBS buffer, and cell culture medium. Detailed physicochemical analysis of the USIRON suspensions provided insight into the magnetic ordering phenomena within the colloid, arising from the formation of uniform clusters displaying a hydrodynamic size of 41 nm. Phantom experiments on the contrast agent (clinical 3 T MRI scanner) revealed an enhanced r(2)/r(1) ratio of 36.4 (r(1)= 5 s(-1) mM(-1) and r(2)= 182 s(-1) mM(-1)) when compared to the clinically approved agents. The potential of the DHAA-Fe(3)O(4) nanoparticles as negative contrast agents for MRI with optimal hydrodynamic size for extended blood circulation times was confirmed by strong contrast observed in T(2)- and T(2)*-weighted images. The cell tests performed with primary human immune-competent cells confirmed the excellent biocompatibility of USIRONs.
Texto completo:
1
Base de dados:
MEDLINE
Assunto principal:
Materiais Biocompatíveis
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Imageamento por Ressonância Magnética
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Água
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Meios de Contraste
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Nanopartículas de Magnetita
Limite:
Humans
Idioma:
En
Revista:
ACS Nano
Ano de publicação:
2011
Tipo de documento:
Article
País de afiliação:
Alemanha