title: Fabrication of MPEG-b-PMAA capped YVO4:Eu nanoparticles with biocompatibility for cell imaging.
abstract: 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.
authors.affiliation: 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. Electronic address: nkcmliu@yahoo.com.
authors.forename: Yue
authors.initials: Y
authors.lastname: Liu
authors.affiliation: 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.
authors.forename: Xiao-Shuang
authors.initials: XS
authors.lastname: Li
authors.affiliation: Beijing Guodian Futong Science and Technology Development CO., LTD, Beijing 100070, China.
authors.forename: Jia
authors.initials: J
authors.lastname: Hu
authors.affiliation: Department of Chemistry, Nankai University, Tianjin 300071, China. Electronic address: guomiao@nankai.edu.cn.
authors.forename: Miao
authors.initials: M
authors.lastname: Guo
authors.affiliation: Integrated Chinese and Western Medicine, Institute of Acute Abdominal Diseases, Tianjin Nankai Hospital, Tianjin 300100, China.
authors.forename: Wei-Jun
authors.initials: WJ
authors.lastname: Liu
authors.affiliation: 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.
authors.forename: Yi-Mei
authors.initials: YM
authors.lastname: Feng
authors.affiliation: 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.
authors.forename: Jing-Ran
authors.initials: JR
authors.lastname: Xie
authors.affiliation: 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.
authors.forename: Gui-Xiang
authors.initials: GX
authors.lastname: Du
mesh_terms: D001672:Biocompatible Materials; D005063:Europium / Q000737:chemistry*; D006863:Hydrogen-Ion Concentration; D046529:Microscopy, Electron, Transmission; D053758:Nanoparticles; D009994:Osmolar Concentration; D011092:Polyethylene Glycols / Q000737:chemistry*; D011109:Polymethacrylic Acids / Q000737:chemistry*; D066244:Proton Magnetic Resonance Spectroscopy; D013997:Time Factors
chemical_list: D001672:Biocompatible Materials; D011109:Polymethacrylic Acids; C030613:polymethacrylic acid; D011092:Polyethylene Glycols; D005063:Europium; C028210:monomethoxypolyethylene glycol
keywords: Biocompatibility; Cell imaging; Fluorescent probe; YVO(4):Eu nanoparticle