Gold nanoparticles functionalized by gadolinium–DTPA conjugate of cysteine as a multimodal bioimaging agent

• Published in: Bioorganic & medicinal chemistry letters Vol. 20; no. 7; pp. 2287 - 2291
• Main Authors: Park, Ji-Ae, Kim, Hee-Kyung, Kim, Joo-Hyun, Jeong, Sang-Won, Jung, Jae-Chang, Lee, Gang-Ho, Lee, Jongmin, Chang, Yongmin, Kim, Tae-Jeong
• Format: Journal Article
• Language: English
• Published: Amsterdam Elsevier Ltd 01.04.2010; Elsevier
• Subjects: Animals; Biological and medical sciences; Contrast Media - chemistry; Contrast media. Radiopharmaceuticals; Cysteine - chemistry; DTPA–cysteine; Gadolinium chelate; Gadolinium DTPA - chemistry; Gold - chemistry; Gold nanoparticles; Investigative techniques, diagnostic techniques (general aspects); Magnetic Resonance Imaging - methods; Medical sciences; Mice; Miscellaneous. Technology; MRI-CT bimodality; Nanoparticles - chemistry; Nanoparticles - ultrastructure; Pharmacology. Drug treatments; Radiodiagnosis. Nmr imagery. Nmr spectrometry; T1 agent; DTPA–cysteine; MRI-CT bimodality; T1 agent; Gadolinium chelate; Gold nanoparticles; Cysteine; Intravenous administration; Nanoparticle; Paramagnetic contrast agent; Gadolinium Complexes; DTPA-cysteine; Surface structure; Characterization; Tissue; Pentetic acid; Modified material; Gold; Rodentia; Organic ligand; Transition metal; Core-shell particle; X ray diffraction; Nuclear magnetic resonance imaging; Sulfur containing aminoacid; Vertebrata; Mammalia; Transmission electron microscopy; Mouse; Animal; Morphology; Distribution; Chelating agent; Lanthanide Complexes; Conjugated compound
• ISSN: 0960-894X; 1464-3405
• DOI: 10.1016/j.bmcl.2010.02.002

The work describes the synthesis and in vivo application of Au@GdL (L = DTPA-bis(amide) conjugate of cysteine) as a highly efficient MRI/CT multimodal contrast agent. The synthesis and characterization of gold nanoparticles coated with Gd-chelate (Au@GdL), where L is a conjugate of DTPA and cysteine, is described. These particles are obtained by the replacement of citrate from the gold nanoparticle surfaces with gadolinium chelate (GdL). The average size of Au@GdL is 14 nm with a loading of GdL reaching up to 2.9 × 10 3 per particles, and they demonstrate very high R1 relaxivity (∼10 5 mM −1 s −1) as well as X-ray attenuation. The R1 relaxivity per [Gd] is 17.9 mM −1 s −1. The present system also exhibits macrophage-specific property, as demonstrated by histological and TEM images as well as CT and MR, rendering itself as a new class of T1 multimodal CT/MR contrast agent.