Nowadays, it is highly desired to develop dual-modal fluorescence and magnetic resonance imaging (FI/MRI) probes in medical imaging because it unites the respective advantages of each imaging modality: high sensitivity of FI and superior spatial resolution of MRI. In this study, a facile strategy to fabricate a new bimodal imaging nanoprobe (Gd-CQDs@N-Fe3O4) was reported by integrating the fluorescence ability of carbon quantum dots (CQDs) and T1 and T2 contrast-enhancing functionality of Gd(III) ions and Fe3O4 nanoparticles into a single hybrid nanostructure. The hybrid composites were investigated by FT-IR, XRD, TEM, XPS, VSM, and so on, which confirmed that Gd-CQDs@N-Fe3O4 nanoparticles were successfully obtained and exhibited superparamagnetic property at room temperature. The derived nanoprobes presented an excitation wavelength-independent emission behavior. In addition, r1 and r2 relaxivities of the synthesized imaging nanoprobes were measured to be 5.16 and 115.6 mM-1 s-1, which nominated Gd-CQDs@N-Fe3O4 nanocomposites as a suitable T1-T2 contrast agent. The Gd-CQDs@N-Fe3O4 nanoparticles combining two synergetic imaging modalities showed great potential in FI/MRI dual-modal imaging for a more complementary and accurate detection.

中文翻译：

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fluorescence掺杂的碳量子点将磁铁矿纳米粒子负载为双峰纳米探针，用于荧光成像和磁共振成像。

如今，非常需要在医学成像中开发双峰荧光和磁共振成像（FI / MRI）探针，因为它结合了每种成像方式的各自优点：FI的高灵敏度和MRI的出色空间分辨率。在这项研究中，通过整合碳量子点（CQDs）的荧光能力以及Gd（III）的T1和T2对比度增强功能，报道了一种制备新的双峰成像纳米探针（Gd-CQDs @ N-Fe3O4）的简便策略。离子和Fe3O4纳米颗粒形成单个杂化纳米结构。通过FT-IR，XRD，TEM，XPS，VSM等对杂化复合材料进行了研究，证实了成功获得了Gd-CQDs @ N-Fe3O4纳米粒子，并在室温下表现出超顺磁性。派生的纳米探针呈现出与激发波长无关的发射行为。另外，测得合成成像纳米探针的r1和r2弛豫度分别为5.16和115.6 mM-1 s-1，从而提名了Gd-CQDs @ N-Fe3O4纳米复合材料作为合适的T1-T2造影剂。结合了两种协同成像方式的Gd-CQDs @ N-Fe3O4纳米粒子在FI / MRI双模式成像中显示出巨大的潜力，可用于更互补和更准确的检测。