Abstract Ultrafine Gd 2 O 3 :Eu 3+ nanocrystals were successfully prepared by a simple reverse microemulsion method and subsequent calcination. Their structural, optical and magnetic properties were investigated using scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray diffraction (XRD), Fourier transform infrared (FTIR), photoluminescence (PL), and magnetic property measurement system (MPMS). The amorphous Gd 2 (CO 3 ) 3 :Eu 3+ colloidal spheres were proved as an intermediate product, and gradually transformed into crystallized Gd 2 O 3 :Eu 3+ with average diameter less than 100 nm. The paramagnetic property of the synthesized Gd 2 O 3 :Eu 3+ nanocrystals were confirmed with its linear hysteresis plot ( M - H ). And Gd 2 O 3 :Eu 3+ nanocrystals showed high contrast T 1 -enhancing modality due to the presence of the Gd 3+ ions onto the particle surface. In addition, the application of the Gd 2 O 3 :Eu 3+ nanocrystals as biotag for cell labeling was reported, red fluorescence from Eu 3+ ions observed by fluorescence microscopy showed that the nanocrystals could permeate the cell membrane. Cytotoxicity studies of the Gd 2 O 3 :Eu 3+ nanocrystals showed no adverse effect on cell viability, evidencing their high biological compatibility. Therefore, the nanoprobe formed from Gd 2 O 3 :Eu 3+ nanocrystals provided the dual modality of optical and magnetic resonance imaging.

中文翻译：

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双功能Gd2O3:Eu3+纳米晶的合成及其在生物医学成像中的应用

摘要 通过简单的反微乳液法和后续煅烧，成功制备了超细Gd 2 O 3 :Eu 3+ 纳米晶。使用扫描电子显微镜 (SEM)、透射电子显微镜 (TEM)、X 射线衍射 (XRD)、傅里叶变换红外 (FTIR)、光致发光 (PL) 和磁性能测量系统研究了它们的结构、光学和磁性能。 MPMS）。无定形Gd 2 (CO 3 ) 3 :Eu 3+ 胶体球被证明是中间产物，并逐渐转化为平均直径小于100 nm的结晶Gd 2 O 3 :Eu 3+ 。合成的 Gd 2 O 3 :Eu 3+ 纳米晶体的顺磁性通过其线性磁滞曲线 (M - H) 得到证实。和 Gd 2 O 3 ：由于颗粒表面上存在 Gd 3+ 离子，Eu 3+ 纳米晶体显示出高对比度 T 1 增强模式。此外，还报道了Gd 2 O 3 :Eu 3+ 纳米晶体作为生物标签用于细胞标记的应用，荧光显微镜观察到的Eu 3+ 离子的红色荧光表明纳米晶体可以渗透细胞膜。Gd 2 O 3 :Eu 3+ 纳米晶体的细胞毒性研究显示对细胞活力没有不利影响，证明它们具有高生物相容性。因此，由Gd 2 O 3 :Eu 3+ 纳米晶体形成的纳米探针提供了光学和磁共振成像的双重模态。通过荧光显微镜观察到的来自 Eu 3+ 离子的红色荧光表明纳米晶体可以渗透细胞膜。Gd 2 O 3 :Eu 3+ 纳米晶体的细胞毒性研究显示对细胞活力没有不利影响，证明它们具有高生物相容性。因此，由Gd 2 O 3 :Eu 3+ 纳米晶体形成的纳米探针提供了光学和磁共振成像的双重模态。通过荧光显微镜观察到的来自 Eu 3+ 离子的红色荧光表明纳米晶体可以渗透细胞膜。Gd 2 O 3 :Eu 3+ 纳米晶体的细胞毒性研究显示对细胞活力没有不利影响，证明它们具有高生物相容性。因此，由Gd 2 O 3 :Eu 3+ 纳米晶体形成的纳米探针提供了光学和磁共振成像的双重模态。