Liu Yue, Li Xiao-Shuang, Hu Jia, Guo Miao, Liu Wei-Jun, Feng Yi-Mei, Xie Jing-Ran, Du Gui-Xiang
Tianjin Key Laboratory of Structure and Performance for Functional Molecules, Key Laboratory of Inorganic-Organic Hybrid Functional Material Chemistry, Ministry of Education, College of Chemistry, Tianjin Normal University, Tianjin 300387, China.
Tianjin Key Laboratory of Structure and Performance for Functional Molecules, Key Laboratory of Inorganic-Organic Hybrid Functional Material Chemistry, Ministry of Education, College of Chemistry, Tianjin Normal University, Tianjin 300387, China.
Colloids Surf B Biointerfaces. 2015 Dec 1;136:721-8. doi: 10.1016/j.colsurfb.2015.10.020. Epub 2015 Oct 17.
A novel nanoparticle with multilayer core-shell architecture for cell imaging is designed and synthesized by coating a fluorescent YVO4:Eu core with a diblock copolymer, MPEG-b-PMAA. The synthesis of YVO4:Eu core, which further makes MPEG-b-PMAA-YVO4:Eu NPs adapt for cell imaging, is guided by the model determined upon the evaluation of pH and CEu%. The PMAA block attached tightly on the YVO4:Eu core forms the inner shell and the MPEG block forms the biocompatible outermost shell. Factors including reaction time, reaction temperature, CEu% and pH are optimized for the preparation of the YVO4:Eu NPs. A precise defined model is established according to analyzing the coefficients of pH and CEu% during the synthesis. The MPEG-b-PMAA-YVO4:Eu NPs, with an average diameter of 24 nm, have a tetragonal structure and demonstrate luminescence in the red region, which lies in a biological window (optical imaging). Significant enhancement in luminescence intensity by MPEG-b-PMAA-YVO4:Eu NPs formation is observed. The capping copolymer MPEG-b-PMAA improves the dispersibility of hydrophobic YVO4:Eu NPs in water, making the NPs stable under different conditions. In addition, the biocompatibility MPEG layer reduces the cytotoxicity of the nanoparticles effectively. 95% cell viability can be achieved at the NPs concentration of 800 mgL(-1) after 24h of culture. Cellular uptake of the MPEG-b-PMAA-YVO4:Eu NPs is evaluated by cell imaging assay, indicating that the NPs can be taken up rapidly and largely by cancerous or non-cancerous cells through an endocytosis mechanism.
通过用二嵌段共聚物MPEG-b-PMAA包覆荧光YVO4:Eu核，设计并合成了一种用于细胞成像的具有多层核壳结构的新型纳米颗粒。YVO4:Eu核的合成是在对pH值和铕含量（CEu%）进行评估后确定的模型指导下进行的，这进一步使MPEG-b-PMAA-YVO4:Eu纳米颗粒适用于细胞成像。紧密附着在YVO4:Eu核上的PMAA嵌段形成内壳，而MPEG嵌段形成生物相容性的最外层壳。对反应时间、反应温度、铕含量（CEu%）和pH值等因素进行了优化，以制备YVO4:Eu纳米颗粒。通过分析合成过程中pH值和铕含量（CEu%）的系数，建立了一个精确的定义模型。平均直径为24 nm的MPEG-b-PMAA-YVO4:Eu纳米颗粒具有四方结构，并在红色区域发光，该区域位于生物窗口（光学成像）内。观察到形成MPEG-b-PMAA-YVO4:Eu纳米颗粒后发光强度显著增强。封端共聚物MPEG-b-PMAA提高了疏水性YVO4:Eu纳米颗粒在水中的分散性，使纳米颗粒在不同条件下保持稳定。此外，生物相容性的MPEG层有效地降低了纳米颗粒的细胞毒性。培养24小时后，在纳米颗粒浓度为每升800毫克（mgL(-1)）时，细胞活力可达到95%。通过细胞成像分析评估了MPEG-b-PMAA-YVO4:Eu纳米颗粒的细胞摄取情况，结果表明纳米颗粒可以通过内吞机制被癌细胞或非癌细胞快速大量摄取。
