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Nano Research 2014, 7(5): 658-669 https://doi.org/10.1007/s12274-014-0420-4
Research Article | Issue | Published: 23 April 2014

AS1411 aptamer-conjugated Gd2O3: Eu nanoparticles for target-specific computed tomography/magnetic resonance/fluorescence molecular imaging

Show Author's Information Tsungrong Kuo1,2,  Weiyun Lai3,4,  Chenghung Li1,  Yanjhan Wun1,  Huancheng Chang2,  Jinnshiun Chen5,  Panchyr Yang6,  Chiachun Chen1,2( )
Department of Chemistry"National Taiwan Normal University", Taipei 116TaiwanChina
Institute of Atomic and Molecular Science"Academia Sinica", Taipei, 106TaiwanChina
Molecular Medicine ProgramTaiwan International Graduate ProgramInstitute of Biomedical Sciences"Academia Sinica", Taipei, 115TaiwanChina
Institute of Biochemistry and Molecular BiologySchool of Life Sciences"National Yang-Ming University", Taipei, 112TaiwanChina
Division of Colorectal SurgeryChang Gung Memorial HospitalChang Gung University, Taoyuan, 333TaiwanChina
College of Medicine"National Taiwan University", Taipei, 106TaiwanChina
Keywords:
aptamer, contrast agent, molecular imaging, Gd2O3 nanoparticles, nanoparticles synthesis
Cite this article:
Kuo T, Lai W, Li C, et al. AS1411 aptamer-conjugated Gd2O3: Eu nanoparticles for target-specific computed tomography/magnetic resonance/fluorescence molecular imaging. Nano Research, 2014, 7(5): 658-669. https://doi.org/10.1007/s12274-014-0420-4
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Abstract Full text About this article

Europium-doped gadolinium oxide (Gd2O3: Eu) nanoparticles have been synthesized, and then their surfaces have been conjugated with nucleolintargeted AS1411 aptamer to form functionalized target-specific Gd2O3: Eu nanoparticles (A-GdO: Eu nanoparticles). The A-GdO: Eu nanoparticles present strong fluorescence in the visible range, high magnetic susceptibility, X-ray attenuation and good biocompatibility. The A-GdO: Eu nanoparticles have been applied to test molecular expression of nucleolin highly expressed CL1-5 lung cancer cells under a confocal microscope. Fluorescence imaging clearly reveals that the nanoparticles can be applied as fluorescent tags for cancer-targeting molecular imaging. Furthermore, taking together their excellent T1 contrast and strong computed tomography (CT) signal, the A-GdO: Eu nanoparticles demonstrate a great capability for use as a dual modality contrast agent for CT and magnetic resonance (MR) molecular imaging. Animal experiments also show that the A-GdO: Eu nanoparticles are able to contrast the tissues of BALB/c mice using CT modality. Moreover, the obvious red fluorescence of A-GdO: Eu nanoparticles can be visualized in a tumor by the naked eye. Overall, our results demonstrate that the A-GdO: Eu nanoparticles can not only serve as new medical contrast agents but also as intraoperative fluorescence imaging probes for guided surgery in the near future.


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About this article

AS1411 aptamer-conjugated Gd2O3: Eu nanoparticles for target-specific computed tomography/magnetic resonance/fluorescence molecular imaging

Show Author's information Tsungrong Kuo1,2, Weiyun Lai3,4, Chenghung Li1, Yanjhan Wun1, Huancheng Chang2, Jinnshiun Chen5, Panchyr Yang6, Chiachun Chen1,2( )
Department of Chemistry"National Taiwan Normal University", Taipei 116TaiwanChina
Institute of Atomic and Molecular Science"Academia Sinica", Taipei, 106TaiwanChina
Molecular Medicine ProgramTaiwan International Graduate ProgramInstitute of Biomedical Sciences"Academia Sinica", Taipei, 115TaiwanChina
Institute of Biochemistry and Molecular BiologySchool of Life Sciences"National Yang-Ming University", Taipei, 112TaiwanChina
Division of Colorectal SurgeryChang Gung Memorial HospitalChang Gung University, Taoyuan, 333TaiwanChina
College of Medicine"National Taiwan University", Taipei, 106TaiwanChina

Abstract

Europium-doped gadolinium oxide (Gd2O3: Eu) nanoparticles have been synthesized, and then their surfaces have been conjugated with nucleolintargeted AS1411 aptamer to form functionalized target-specific Gd2O3: Eu nanoparticles (A-GdO: Eu nanoparticles). The A-GdO: Eu nanoparticles present strong fluorescence in the visible range, high magnetic susceptibility, X-ray attenuation and good biocompatibility. The A-GdO: Eu nanoparticles have been applied to test molecular expression of nucleolin highly expressed CL1-5 lung cancer cells under a confocal microscope. Fluorescence imaging clearly reveals that the nanoparticles can be applied as fluorescent tags for cancer-targeting molecular imaging. Furthermore, taking together their excellent T1 contrast and strong computed tomography (CT) signal, the A-GdO: Eu nanoparticles demonstrate a great capability for use as a dual modality contrast agent for CT and magnetic resonance (MR) molecular imaging. Animal experiments also show that the A-GdO: Eu nanoparticles are able to contrast the tissues of BALB/c mice using CT modality. Moreover, the obvious red fluorescence of A-GdO: Eu nanoparticles can be visualized in a tumor by the naked eye. Overall, our results demonstrate that the A-GdO: Eu nanoparticles can not only serve as new medical contrast agents but also as intraoperative fluorescence imaging probes for guided surgery in the near future.

Keywords: aptamer, contrast agent, molecular imaging, Gd2O3 nanoparticles, nanoparticles synthesis

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Publication history
Copyright
Acknowledgements

Publication history

Received: 08 July 2013
Revised: 10 January 2014
Accepted: 16 January 2014
Published: 23 April 2014
Issue date: May 2014

Copyright

© Tsinghua University Press and Springer-Verlag Berlin Heidelberg 2014

Acknowledgements

Acknowledgements

The paper is dedicated to the memory of Dr. Konan Pei who contributed to the main idea of the experiment and passed away in 2011. This work was supported by the "National Science Council", Taiwan, China (NSC 100-2113-M-003-010-MY3). We thank the Taiwan Mouse Clinic which is funded by the "National Research Program for Biopharmaceuticals" (NRPB) at the "National Science Council" (NSC) of Taiwan, China for technical support in CT imaging experiments.

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