title: Phosphorescent polymeric nanoparticles by coordination cross-linking as a platform for luminescence imaging and photodynamic therapy.
abstract: Water-soluble phosphorescent polymeric nanoparticles with an average diameter of approximately 100 nm were synthesized by a coordination cross-linking reaction. The pyridine blocks in poly(4-vinyl pyridine-b-ethylene oxide) (P4VP-b-PEO) were cross-linked by the iridium chloride-bridged dimer in DMF solution. Owing to the presence of an iridium complex with different ligands in the core of the polymeric nanoparticles, NP-1, NP-2, and NP-3 showed bright green, yellow, and red phosphorescence, respectively. PEG chains in the shell gave the polymeric nanoparticles solubility and biocompatibility, which was confirmed by an MTT assay using HeLa cells as a model cancer cell line. The flow cytometry and laser confocal fluorescence microscopy results revealed NP-2, as an example, could be effectively uptaken by HeLa cells. Therefore, these polymeric nanoparticles can be used as luminescent probes for living cells. In addition, (1) O2 could be effectively generated in the presence of NP-2 upon irradiation with visible light (λ>400 nm, 300 mW cm(-2) ), which was confirmed by a clear decrease in the fluorescence intensity of 9,10-dimethylanthracene (DMA). After incubation with NP-2 at a concentration of 200 μg mL(-1) for 6 h, approximately 90 % of HeLa cells were effectively ablated upon irradiation with visible light for only 10 min, indicating the potential for photodynamic therapy with polymeric nanoparticles.
authors.affiliation: The Key Laboratory of Resource Chemistry of Ministry of Education, Shanghai Key Laboratory of Rare Earth Functional Materials, Shanghai Municipal Education Committee, Key Laboratory of Molecular Imaging Probes and Sensors, Shanghai Normal University, Shanghai 200234 (P.R. China), Fax: (+86) 21-6432-2511.
authors.forename: Yang
authors.initials: Y
authors.lastname: Lu
authors.forename: Fengfeng
authors.initials: F
authors.lastname: Xue
authors.forename: Zhiguo
authors.initials: Z
authors.lastname: Zhou
authors.forename: Min
authors.initials: M
authors.lastname: Shi
authors.forename: Yuping
authors.initials: Y
authors.lastname: Yan
authors.forename: Lijie
authors.initials: L
authors.lastname: Qin
authors.forename: Hong
authors.initials: H
authors.lastname: Yang
authors.forename: Shiping
authors.initials: S
authors.lastname: Yang
mesh_terms: D056831:Coordination Complexes / Q000737:chemistry / Q000627:therapeutic use*; D006367:HeLa Cells; D006801:Humans; D007495:Iridium / Q000737:chemistry / Q000627:therapeutic use*; D049449:Luminescence; D018613:Microscopy, Confocal; D053758:Nanoparticles / Q000737:chemistry / Q000627:therapeutic use*; D009369:Neoplasms / Q000175:diagnosis* / Q000188:drug therapy*; D061848:Optical Imaging; D010778:Photochemotherapy; D011092:Polyethylene Glycols / Q000737:chemistry / Q000627:therapeutic use; D014753:Vinyl Compounds / Q000737:chemistry / Q000627:therapeutic use
chemical_list: D056831:Coordination Complexes; D014753:Vinyl Compounds; C520176:poly(4-vinylpyridine)-block-poly(ethylene oxide); D011092:Polyethylene Glycols; D007495:Iridium
keywords: iridium; luminescence imaging; nanoparticles; phosphorescence; photodynamic therapy