title: Enhanced dual contrast agent, Co(2+)-doped NaYF4:Yb(3+),Tm(3+) nanorods, for near infrared-to-near infrared upconversion luminescence and magnetic resonance imaging.
abstract: Dual-modality imaging with magnetic resonance (MR) and upconversion luminescence (UCL) is a promising technique for molecular imaging in biomedical research. Multifunctional lanthanide-based nanoparticles have been widely investigated as agents for contrast enhanced MR and fluorescence imaging. However, the use of rare earth fluoride nanoparticles for dual-modality imaging of T2-weighted MR and UCL is rarely reported. We find that NaYF4:Yb(3+),Tm(3+),Co(2+) (MUC) nanorods can be applied as a high-performance dual contrast agent for both T2-weighted MR and UCL dual-modality imaging. After modification with 6-O-carboxymethyl chitosan (OCC), MUC nanorods can be endocytosed by cells without showing signs of cytotoxicity. High-quality UCL images of living cells incubated with MUC-OCC nanorods were acquired on a near-infrared (NIR) confocal microscopy under the excitation at 980 nm. Moreover, MUC-OCC nanorods display high transverse (r2) relaxivities in vitro. The application of low-dose MUC-OCC nanorods for NIR-to-NIR UCL and MR dual-modality in vivo imaging was also carried out successfully. In addition, the toxicity of MUC-OCC nanorods was evaluated by MTT assay, serological tests and histological analysis of visceral organs.
authors.affiliation: Jiangsu Collaborative Innovation Center of Biomedical Functional Materials, Jiangsu Key Laboratory of Biomedical Materials, College of Chemistry and Materials Science, Nanjing Normal University, 1 Wenyuan Road, Nanjing 210046, China; School of Chemistry & Chemical Engineering, Nanjing University, 22 Hankou Road, Nanjing 210093, China.
authors.forename: Ao
authors.initials: A
authors.lastname: Xia
authors.affiliation: Jiangsu Collaborative Innovation Center of Biomedical Functional Materials, Jiangsu Key Laboratory of Biomedical Materials, College of Chemistry and Materials Science, Nanjing Normal University, 1 Wenyuan Road, Nanjing 210046, China.
authors.forename: Xiaofeng
authors.initials: X
authors.lastname: Zhang
authors.affiliation: Jiangsu Collaborative Innovation Center of Biomedical Functional Materials, Jiangsu Key Laboratory of Biomedical Materials, College of Chemistry and Materials Science, Nanjing Normal University, 1 Wenyuan Road, Nanjing 210046, China.
authors.forename: Jun
authors.initials: J
authors.lastname: Zhang
authors.affiliation: Jiangsu Collaborative Innovation Center of Biomedical Functional Materials, Jiangsu Key Laboratory of Biomedical Materials, College of Chemistry and Materials Science, Nanjing Normal University, 1 Wenyuan Road, Nanjing 210046, China.
authors.forename: Yunyun
authors.initials: Y
authors.lastname: Deng
authors.affiliation: School of Chemistry & Chemical Engineering, Nanjing University, 22 Hankou Road, Nanjing 210093, China.
authors.forename: Qiang
authors.initials: Q
authors.lastname: Chen
authors.affiliation: School of Chemistry & Chemical Engineering, Nanjing University, 22 Hankou Road, Nanjing 210093, China.
authors.forename: Shishan
authors.initials: S
authors.lastname: Wu
authors.affiliation: Jiangsu Collaborative Innovation Center of Biomedical Functional Materials, Jiangsu Key Laboratory of Biomedical Materials, College of Chemistry and Materials Science, Nanjing Normal University, 1 Wenyuan Road, Nanjing 210046, China. Electronic address: huangxiaohuabio@hotmail.com.
authors.forename: Xiaohua
authors.initials: X
authors.lastname: Huang
authors.affiliation: Jiangsu Collaborative Innovation Center of Biomedical Functional Materials, Jiangsu Key Laboratory of Biomedical Materials, College of Chemistry and Materials Science, Nanjing Normal University, 1 Wenyuan Road, Nanjing 210046, China; School of Chemistry & Chemical Engineering, Nanjing University, 22 Hankou Road, Nanjing 210093, China. Electronic address: shenjianbio@hotmail.com.
authors.forename: Jian
authors.initials: J
authors.lastname: Shen
mesh_terms: D000818:Animals; D045744:Cell Line, Tumor; D002470:Cell Survival; D048271:Chitosan / Q000031:analogs & derivatives / Q000737:chemistry; D003287:Contrast Media / Q000737:chemistry*; D005260:Female; D056945:Hep G2 Cells; D006801:Humans; D028581:Lanthanoid Series Elements / Q000737:chemistry; D049449:Luminescence; D008279:Magnetic Resonance Imaging / Q000379:methods*; D051379:Mice; D008819:Mice, Nude; D018613:Microscopy, Confocal / Q000379:methods; D053758:Nanoparticles / Q000737:chemistry; D043942:Nanotubes / Q000737:chemistry*; D019265:Spectroscopy, Near-Infrared / Q000379:methods*; D018675:Toxicity Tests
chemical_list: D003287:Contrast Media; D028581:Lanthanoid Series Elements; C504164:O-carboxymethylchitosan; D048271:Chitosan
keywords: Lanthanide nanoparticle; Magnetic resonance imaging; Multi-modality imaging; Nanorod; Rare earth nanomaterials; Upconversion luminescence