title: X-ray computed tomography imaging of a tumor with high sensitivity using gold nanoparticles conjugated to a cancer-specific antibody via polyethylene glycol chains on their surface.
abstract: Contrast agents are often used to enhance the contrast of X-ray computed tomography (CT) imaging of tumors to improve diagnostic accuracy. However, because the iodine-based contrast agents currently used in hospitals are of low molecular weight, the agent is rapidly excreted from the kidney or moves to extravascular tissues through the capillary vessels, depending on its concentration gradient. This leads to nonspecific enhancement of contrast images for tissues. Here, we created gold (Au) nanoparticles as a new contrast agent to specifically image tumors with CT using an enhanced permeability and retention (EPR) effect. Au has a higher X-ray absorption coefficient than does iodine. Au nanoparticles were supported with polyethylene glycol (PEG) chains on their surface to increase the blood retention and were conjugated with a cancer-specific antibody via terminal PEG chains. The developed Au nanoparticles were injected into tumor-bearing mice, and the distribution of Au was examined with CT imaging, transmission electron microscopy, and elemental analysis using inductively coupled plasma optical emission spectrometry. The results show that specific localization of the developed Au nanoparticles in the tumor is affected by a slight difference in particle size and enhanced by the conjugation of a specific antibody against the tumor.
authors.affiliation: Department of Nano-Medical Science, Graduate School of Medicine, Tohoku University , Sendai , Japan.
authors.forename: Tomohiko
authors.initials: T
authors.lastname: Nakagawa
authors.affiliation: Department of Nano-Medical Science, Graduate School of Medicine, Tohoku University, Sendai, Japan; Department of Medical Physics, Graduate School of Medicine, Tohoku University, Sendai, Japan.
authors.forename: Kohsuke
authors.initials: K
authors.lastname: Gonda
authors.affiliation: Department of Advanced Surgical Science and Technology, Graduate School of Medicine, Tohoku University , Sendai , Japan.
authors.forename: Takashi
authors.initials: T
authors.lastname: Kamei
authors.affiliation: Department of Nano-Medical Science, Graduate School of Medicine, Tohoku University , Sendai , Japan.
authors.forename: Liman
authors.initials: L
authors.lastname: Cong
authors.affiliation: Department of Nano-Medical Science, Graduate School of Medicine, Tohoku University , Sendai , Japan.
authors.forename: Yoh
authors.initials: Y
authors.lastname: Hamada
authors.affiliation: Department of Nano-Medical Science, Graduate School of Medicine, Tohoku University , Sendai , Japan.
authors.forename: Narufumi
authors.initials: N
authors.lastname: Kitamura
authors.affiliation: Department of Surgical Oncology, Graduate School of Medicine, Tohoku University , Sendai , Japan.
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Tada
authors.affiliation: Department of Surgical Oncology, Graduate School of Medicine, Tohoku University , Sendai , Japan.
authors.forename: Takanori
authors.initials: T
authors.lastname: Ishida
authors.affiliation: Development Department 4, Business Development Division, Business Development Headquarters, Konica Minolta, Inc. , Tokyo , Japan.
authors.forename: Takuji
authors.initials: T
authors.lastname: Aimiya
authors.affiliation: Development Department 4, Business Development Division, Business Development Headquarters, Konica Minolta, Inc. , Tokyo , Japan.
authors.forename: Naoko
authors.initials: N
authors.lastname: Furusawa
authors.affiliation: Development Department 4, Business Development Division, Business Development Headquarters, Konica Minolta, Inc. , Tokyo , Japan.
authors.forename: Yasushi
authors.initials: Y
authors.lastname: Nakano
authors.affiliation: Department of Nano-Medical Science, Graduate School of Medicine, Tohoku University, Sendai, Japan; Department of Surgical Oncology, Graduate School of Medicine, Tohoku University, Sendai, Japan.
authors.forename: Noriaki
authors.initials: N
authors.lastname: Ohuchi
keywords: 30 Bio-inspired and biomedical materials; 504 X-ray / Neutron diffraction and scattering; CT; contrast agent; gold; nanoparticle; tumor