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Manipulating the Power of an Additional Phase: A Flower-like Au-Fe3O4 Optical Nanosensor for Imaging Protease Expressions In vivo

Laboratory of Molecular Imaging and Nanomedicine, National Institute of Biomedical Imaging and Bioengineering, National Institutes of Health, Bethesda, Maryland 20892, USA.
ACS Nano (Impact Factor: 12.88). 03/2011; 5(4):3043-51. DOI: 10.1021/nn200161v
Source: PubMed

ABSTRACT We and others have recently proposed the synthesis of composite nanoparticles that offer strongly enhanced functionality. Here we have used a flower-shaped Au-Fe(3)O(4) nanoparticle as a template to construct an optical probe containing Cy5.5-GPLGVRG-TDOPA on the iron oxide surface and SH-PEG(5000) on the gold surface that can be specifically activated by matrix metalloproteinases expressed in tumors. Gold nanoparticles have excellent quenching properties, but labile surface chemistry in vivo; on the other hand, iron oxide nanoparticles afford robust surface chemistry, but are suboptimal as energy receptors. By a marriage of the two, we have produced a unified structure with performance that is unachievable with the separate components. Our results are a further demonstration that the architecture of nanoparticles can be modulated to tailor their function as molecular imaging/therapeutic agents.

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Available from: Ki Young Choi, Aug 28, 2015
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    • "In particular, Au-Fe x O y MP-NHs have attracted a lot of attention and are thought of as potential candidates for applications in magnetic resonance imaging, magnetic/photo-induced hyperthermia, DNA sensing, cell sorting by method of magnetic separation, etc [7] [9]. Recent reports have shown evidence of direct interaction due to spin polarization transfer between the magnetic moment and the non-magnetic–plasmonic counterpart, thereby inducing finite magnetization in Au [4]. "
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    • "In particular, Au-Fe x O y MP-NHs have attracted a lot of attention and are thought of as potential candidates for applications in magnetic resonance imaging, magnetic/photo-induced hyperthermia, DNA sensing, cell sorting by method of magnetic separation, etc [7] [9]. Recent reports have shown evidence of direct interaction due to spin polarization transfer between the magnetic moment and the non-magnetic–plasmonic counterpart, thereby inducing finite magnetization in Au [4]. "
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