title: A europium(III) complex as an efficient singlet oxygen luminescence probe.
abstract: A new europium(III) complex, [4'-(10-methyl-9-anthryl)-2,2':6',2"-terpyridine-6,6"-diyl]bis(methylenenitrilo) tetrakis(acetate)-Eu(3+), was designed and synthesized as a highly sensitive and selective time-gated luminescence probe for singlet oxygen ((1)O2). The new probe is highly water soluble with a large stability constant of approximately 10(21) and a wide pH available range (pH 3-10), and can specifically react with (1)O2 to form its endoperoxide (EP-MTTA-Eu(3+)) with a high reaction rate constant at 10(10) M(-1) s(-1), accompanied by the remarkable increases of luminescence quantum yield from 0.90% to 13.8% and lifetime from 0.80 to 1.29 ms, respectively. The wide applicability of the probe was demonstrated by detection of (1)O2 generated from a MoO(4)(2-)/H(2)O2 system, a photosensitization system of 5,10,15,20-tetrakis(1-methyl-4-pyridinio)porphyrin tetra(p-toluenesulfonate) (TMPyP), and a horseradish peroxidase catalyzed aerobic oxidation system of indole-3-acetic acid (IAA). In addition, it was found that the new probe could be easily transferred into living HeLa cells by incubation with TMPyP. A time-gated luminescence imaging technique that can fully eliminate the short-lived background fluorescence from TMPyP and cell components has been successfully developed for monitoring the time-dependent generation of (1)O2 in living cells.
authors.affiliation: Department of Analytical Chemistry, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian 116023, P. R. China.
authors.forename: Bo
authors.initials: B
authors.lastname: Song
authors.forename: Guilan
authors.initials: G
authors.lastname: Wang
authors.forename: Mingqian
authors.initials: M
authors.lastname: Tan
authors.forename: Jingli
authors.initials: J
authors.lastname: Yuan
mesh_terms: D002384:Catalysis; D002412:Cations; D005063:Europium / Q000737:chemistry*; D006367:HeLa Cells; D006735:Horseradish Peroxidase / Q000378:metabolism; D006801:Humans; D006863:Hydrogen-Ion Concentration; D049408:Luminescent Agents / Q000138:chemical synthesis*; D008163:Luminescent Measurements; D015335:Molecular Probes / Q000138:chemical synthesis*; D009942:Organometallic Compounds / Q000138:chemical synthesis*; D010084:Oxidation-Reduction; D010100:Oxygen / Q000737:chemistry / Q000378:metabolism; D012680:Sensitivity and Specificity; D026082:Singlet Oxygen / Q000737:chemistry*; D012995:Solubility; D013997:Time Factors; D014867:Water / Q000737:chemistry
chemical_list: C522821:(4'-(10-methyl-9-anthryl)-2,2'-6',2''-terpyridine-6,6''-diyl)bis(methylenenitrilo) tetrakis(acetate)-Eu(3+); D002412:Cations; D049408:Luminescent Agents; D015335:Molecular Probes; D009942:Organometallic Compounds; D014867:Water; D026082:Singlet Oxygen; D005063:Europium; D006735:Horseradish Peroxidase; D010100:Oxygen