X-ray imaging of newly-developed gadolinium compound/silica core–shell particles

• Published in: Journal of sol-gel science and technology 2011-09, Vol.59 (3), p.650-657
• Main Authors: Morimoto, Hikaru, Minato, Marie, Nakagawa, Tomohiko, Sato, Masahide, Kobayashi, Yoshio, Gonda, Kohsuke, Takeda, Motohiro, Ohuchi, Noriaki, Suzuki, Noboru
• Format: Article
• Language: English
• Subjects: Anhydrides; Carboxyl group; Ceramics; Chemistry; Chemistry and Materials Science; Colloidal gels. Colloidal sols; Colloidal state and disperse state; Colloiding; Colloids; Composites; Contrast agents; Core-shell structure; Exact sciences and technology; Gadolinium; Gadolinium compounds; General and physical chemistry; Glass; Image contrast; Inorganic Chemistry; Light scattering; Materials Science; Nanoparticles; Nanotechnology; Natural Materials; Optical and Electronic Materials; Organs; Original Paper; Physical and chemical studies. Granulometry. Electrokinetic phenomena; Silicon dioxide; Sodium hydroxide; X ray imagery
• ISSN: 0928-0707; 1573-4846
• DOI: 10.1007/s10971-011-2540-6

A preparation method for gadolinium compound (Gd) nanoparticles coated with silica (Gd/SiO 2 ) is proposed. Gd nanoparticles were prepared with a homogeneous precipitation method at 80 °C using 1.0 × 10 −3 M Gd(NO 3 ) 3 and 0.5 M urea in the presence of 1.0 g/L stabilizer. Among stabilizers examined. Sodium n-dodecyl sulfate (SDS) was suitable as the stabilizer for preparing small Gd nanoparticles, and consequently Gd nanoparticles with a size of 46.2 ± 12.4 nm were prepared using the SDS. Silica-coating of the Gd nanoparticles was performed by a Stöber method at room temperature using 0.013 M TEOS and 2.0 × 10 −3  M NaOH in water/1-propanol solution in the presence of 1.0 × 10 −3  M Gd nanoparticles, which resulted in production of Gd/SiO 2 particles with an average size of 64.2 ± 14.4 nm. The Gd/SiO 2 particles were surface-modified with 3-aminopropyltrimethoxysilane and succinic anhydride. It was confirmed by measurement of electrophretic light scattering that amino group or carboxyl group was introduced onto the Gd/SiO 2 particles. The gadolinium concentration of 1.0 × 10 −3  M in the as-prepared colloid solution was increased up to a gadolinium concentration of 0.4 M by centrifugation. The core–shell structure of Gd/SiO 2 particles was undamaged, and the colloid solution was still colloidally stable, even after the concentrating process. The concentrated Gd/SiO 2 colloid solution showed an X-ray image with contrast as high as a commercial Gd complex contrast agent. Internal organs in a mouse could be imaged injecting the concentrated colloid solution into it.