Hu Hao, Huang Peng, Weiss Orit Jacobson, Yan Xuefeng, Yue Xuyi, Zhang Molly Gu, Tang Yuxia, Nie Liming, Ma Ying, Niu Gang, Wu Kaichun, Chen Xiaoyuan
State Key Laboratory of Cancer Biology & Xijing Hospital of Digestive Diseases, Fourth Military Medical University, Xi'an, China; Laboratory of Molecular Imaging and Nanomedicine (LOMIN), National Institute of Biomedical Imaging and Bioengineering (NIBIB), National Institutes of Health (NIH), Bethesda, MD, USA.
Laboratory of Molecular Imaging and Nanomedicine (LOMIN), National Institute of Biomedical Imaging and Bioengineering (NIBIB), National Institutes of Health (NIH), Bethesda, MD, USA.
Biomaterials. 2014 Dec;35(37):9868-9876. doi: 10.1016/j.biomaterials.2014.08.038. Epub 2014 Sep 15.
Self-illuminating fluorescence imaging without autofluorescence background interference has recently aroused more research interests in molecular imaging. Currently, only a few self-illuminating probes were developed, based mainly on toxic quantum dots such as CdSe, CdTe. Herein, we report a novel design of nontoxic self-illuminating gold nanocluster ((64)Cu-doped AuNCs) for dual-modality positron emission tomography (PET) and near-infrared (NIR) fluorescence imaging based on Cerenkov resonance energy transfer (CRET). PET radionuclide (64)Cu was introduced by a chelator-free doping method, which played dual roles as the energy donor and the PET imaging source. Meanwhile, AuNCs acted as the energy acceptor for NIR fluorescence imaging. (64)Cu-doped AuNCs exhibited efficient CRET-NIR and PET imaging both in vitro and in vivo. In a U87MG glioblastoma xenograft model, (64)Cu-doped AuNCs showed high tumor uptake (14.9 %ID/g at 18 h) and produced satisfactory tumor self-illuminating NIR images in the absence of external excitation. This self-illuminating nanocluster with non-toxicity and good biocompatibility can be employed as a novel imaging contrast agent for biomedical applications, especially for molecular imaging.
无自发荧光背景干扰的自发光荧光成像最近在分子成像领域引起了更多的研究兴趣。目前，仅开发了少数几种自发光探针，主要基于有毒的量子点，如CdSe、CdTe。在此，我们报道了一种基于切伦科夫共振能量转移（CRET）的用于双模态正电子发射断层扫描（PET）和近红外（NIR）荧光成像的新型无毒自发光金纳米团簇（（64）Cu掺杂的AuNCs）的设计。PET放射性核素（64）Cu通过无螯合剂掺杂方法引入，其作为能量供体和PET成像源发挥双重作用。同时，AuNCs作为NIR荧光成像的能量受体。（64）Cu掺杂的AuNCs在体外和体内均表现出高效的CRET-NIR和PET成像。在U87MG胶质母细胞瘤异种移植模型中，（64）Cu掺杂的AuNCs显示出高肿瘤摄取（18小时时为14.9 %ID/g），并且在没有外部激发的情况下产生了令人满意的肿瘤自发光NIR图像。这种具有无毒和良好生物相容性的自发光纳米团簇可作为一种新型成像造影剂用于生物医学应用，特别是分子成像。
