title: Magnetic PEGylated Pt3Co nanoparticles as a novel MR contrast agent: in vivo MR imaging and long-term toxicity study.
abstract: Magnetic resonance (MR) imaging using magnetic nanoparticles as the contrast agent has been extensively explored in biomedical imaging and disease diagnosis. Herein, we develop biocompatible polymer coated ultra-small Pt3Co magnetic nanoparticles as a new T2-weighted MR imaging contrast agent. A unique class of alloy Pt3Co nanoparticles is synthesized through a thermal decomposition method. After being modified with polyethylene glycol (PEG), the obtained Pt3Co-PEG nanoparticles exhibit an extremely high T2-weighted relaxivity rate (r2) up to 451.2 mM s(-1), which is much higher than that of Resovist®, a commercial T2-MR contrast agent used in the clinic. In vitro experiments indicate no obvious cytotoxicity of Pt3Co-PEG nanoparticles to various cell lines. After intravenous injection of Pt3Co-PEG nanoparticles, in vivo T2-weighted MR imaging of tumor-bearing mice reveals strong tumor contrast, which is much higher than that offered by injecting Resovist®. We further study the long-term biodistribution and toxicology of this new type of MR contrast nanoparticles after intravenous injection into healthy mice. Despite the significant retention of Pt3Co-PEG nanoparticles in the mouse liver and spleen, no appreciable toxicity of these nanoparticles to the treated animals has been noted in our detailed histological and hematological analysis over a course of 60 days. Our work demonstrates that functionalized Pt3Co nanoparticles may be a promising new type of T2-weighted MR contrast agent potentially useful in biomedical imaging and diagnosis.
authors.affiliation: Department of Radiology, The First Affiliated Hospital of Soochow University, Suzhou, Jiangsu 215006, China. liyonggang224@163.com ilguoliang@sohu.com.
authors.forename: Shengnan
authors.initials: S
authors.lastname: Yin
authors.forename: Zhiwei
authors.initials: Z
authors.lastname: Li
authors.forename: Liang
authors.initials: L
authors.lastname: Cheng
authors.forename: Chao
authors.initials: C
authors.lastname: Wang
authors.forename: Yumeng
authors.initials: Y
authors.lastname: Liu
authors.forename: Qian
authors.initials: Q
authors.lastname: Chen
authors.forename: Hua
authors.initials: H
authors.lastname: Gong
authors.forename: Liang
authors.initials: L
authors.lastname: Guo
authors.forename: Yonggang
authors.initials: Y
authors.lastname: Li
authors.forename: Zhuang
authors.initials: Z
authors.lastname: Liu
mesh_terms: D000818:Animals; D002478:Cells, Cultured; D003035:Cobalt / Q000737:chemistry* / Q000633:toxicity; D003287:Contrast Media / Q000138:chemical synthesis* / Q000737:chemistry / Q000633:toxicity; D057809:HEK293 Cells; D006801:Humans; D008279:Magnetic Resonance Imaging / Q000379:methods*; D059346:Magnets / Q000737:chemistry / Q000633:toxicity; D008422:Materials Testing; D053768:Metal Nanoparticles / Q000737:chemistry* / Q000633:toxicity; D051379:Mice; D008807:Mice, Inbred BALB C; D017671:Platinum Compounds / Q000737:chemistry* / Q000633:toxicity; D011092:Polyethylene Glycols / Q000737:chemistry* / Q000633:toxicity; D013997:Time Factors
chemical_list: D003287:Contrast Media; D017671:Platinum Compounds; D003035:Cobalt; D011092:Polyethylene Glycols