Du Qijun, Huang Zhongbing, Wu Zhi, Meng Xianwei, Yin Guangfu, Gao Fabao, Wang Lei
College of Materials Science and Engineering, Sichuan University, Chengdu, 610065, People's Republic of China.
Dalton Trans. 2015 Mar 7;44(9):3934-40. doi: 10.1039/c4dt03444a.
The biocompatibility of multifunctional nanomaterials is very important for their clinical applications. Herein, the hexagonal crystal Eu-doped GdPO4 nanorods (NRs) in the template of silk fibroin (SF) peptides are successfully synthesized via a mineralization process. The sizes of the Eu-doped GdPO4 NRs with SF peptides (SF-NRs) are ∼150 nm in length and ∼10 nm in diameter. The Eu-doped SF-NRs have strong pink luminescence and a mass magnetic susceptibility value of 1.27 emu g(-1) in 20,000 G of magnetic field due to Eu ion doping. The cell test indicates that the Eu-doped SF-NRs obviously promote the viability of cells at an NR concentration of 25-200 μg mL(-1). A growth mechanism of Eu-doped GdPO4 SF-NRs is proposed to explain their strong cellular luminescence, magnetic resonance (MR) imaging and good cyto-compatibility. Compared to NRs without SF, the Eu-doped SF-NRs not only exhibit a higher effective positive signal-enhancement ability (the longitudinal relaxivity r1 value is 1.38 (Gd mM s)(-1)) and in vivo T1 weighted MR imaging enhancement under a 7.0 T MRI system, but also show the better luminescence imaging of living cells under the fluorescence microscope. This indicates that the Eu-doped SF-NRs have potential as T1 MRI contrast agents and optical imaging probes.
多功能纳米材料的生物相容性对其临床应用非常重要。在此，通过矿化过程成功合成了丝素蛋白（SF）肽模板中的六方晶系铕掺杂磷酸钆纳米棒（NRs）。含SF肽的铕掺杂磷酸钆纳米棒（SF-NRs）长度约为150 nm，直径约为10 nm。由于铕离子掺杂，铕掺杂的SF-NRs具有强烈的粉红色发光，在20,000 G磁场中的质量磁化率值为1.27 emu g(-1)。细胞测试表明，在NR浓度为25 - 200 μg mL(-1)时，铕掺杂的SF-NRs明显促进细胞活力。提出了铕掺杂磷酸钆SF-NRs的生长机制来解释其强烈的细胞发光、磁共振（MR）成像和良好的细胞相容性。与不含SF的纳米棒相比，铕掺杂的SF-NRs不仅在7.0 T MRI系统下表现出更高的有效正信号增强能力（纵向弛豫率r1值为1.38 (Gd mM s)(-1)）和体内T1加权MR成像增强效果，而且在荧光显微镜下对活细胞的发光成像效果更好。这表明铕掺杂的SF-NRs有潜力作为T1 MRI造影剂和光学成像探针。
