Yi Zhigao, Li Xiaolong, Lu Wei, Liu Hongrong, Zeng Songjun, Hao Jianhua
College of Physics and Information Science and Key Laboratory of Low-dimensional Quantum Structures and Quantum Control of the Ministry of Education, Hunan Normal University, Changsha 410081, Hunan, China.
J Mater Chem B. 2016 Apr 21;4(15):2715-2722. doi: 10.1039/c5tb02375k. Epub 2016 Apr 5.
Lanthanide nanoparticles (NPs), which are known as upconversion fluorescence probes for multimodal bioimaging, including magnetic resonance imaging (MRI), have attracted much attentions. In MRI, conventional contrast agents are generally employed separately in a single type of MRI. T- and T-weighted MRI alone have unique limitations; therefore, it is urgently necessary to combine the two modalities so as to be able to provide more comprehensive and synergistic diagnostic information than the single modality of MRI. Unfortunately, there is a lack of advanced materials as enhancing agents which are fully suitable for bimodal MRI. Here, we report a new class of hybrid lanthanide nanoparticles as synergistic contrast agents in T/T dual-weighted MRI and imaging-directed tumor diagnosis. The r/r value of BaGdF NPs can be readily adjusted from 2.8 to 334.8 by doping with 0%, 50%, or 100% Ln (Ln = Yb, Er, or Dy), respectively. Among these, BaGdF:50% Er NPs were successfully used as binary contrast agents for T/T dual-weighted MRI and synergistic tumor diagnosis in vivo. These findings reveal that the longitudinal and transverse relaxivities of these Gd-based NPs can be controlled by tuning the Ln dopants and their concentrations, providing a simple and general method for designing simultaneous T/T enhancing agents.
镧系纳米颗粒（NPs）作为用于多模态生物成像（包括磁共振成像（MRI））的上转换荧光探针，已引起了广泛关注。在MRI中，传统的造影剂通常在单一类型的MRI中单独使用。单独的T加权和T加权MRI都有其独特的局限性；因此，迫切需要将这两种模式结合起来，以便能够提供比单一MRI模式更全面和协同的诊断信息。不幸的是，缺乏完全适用于双模态MRI的先进增强剂材料。在此，我们报道了一类新型的混合镧系纳米颗粒，作为T/T双加权MRI和成像引导肿瘤诊断中的协同造影剂。通过分别掺杂0%、50%或100%的Ln（Ln = Yb、Er或Dy），BaGdF NPs的r/r值可以很容易地从2.8调整到334.8。其中，BaGdF:50% Er NPs成功地用作T/T双加权MRI的二元造影剂，并在体内实现了协同肿瘤诊断。这些发现表明，这些基于Gd的NPs的纵向和横向弛豫率可以通过调整Ln掺杂剂及其浓度来控制，为设计同时增强T/T的试剂提供了一种简单通用的方法。
