125330-07-6Relevant articles and documents
Photoinduced electron transfer in supramolecular ruthenium-porphyrin assemblies
Rota Martir, Diego,Averardi, Mattia,Escudero, Daniel,Jacquemin, Denis,Zysman-Colman, Eli
, p. 2255 - 2262 (2017)
We present dynamic supramolecular systems composed of a Ru(ii) complex of the form of [Ru(dtBubpy)2(qpy)][PF6]2 (where dtBubpy is 4,4′-di-tert-butyl-2,2′-dipyridyl and qpy is 4,4′:2′,2′′:4′′,4′′′-quaterpyridine) and zinc t
Derivatives of Tris(2,2'-bipyridine)ruthenium(II) with Pendant Pyridyl or Phenol Ligands
Hayes, Martin A.,Meckel, Claudia,Schatz, Erik,Ward, Michael D.
, p. 703 - 708 (1992)
Reaction of 2,2':4',4''-terpyridine or 4-(4-pyridyl)-2,2':4',4''-terpyridine with (bipy = 2,2'-bipyridine) and of 4-(p-methoxyphenyl)-2,2'-bipyridine with followed by demethylation of the anisole with BBr3, yields derivatives of Ru(bipy)3(2+) which contain externally directed pendant pyridyl or phenol groups capable of ligation to other metals.These complexes are proposed as 'building blocks' for photoactive polynuclear complexes containing the Ru(bipy)3(2+) chromophore.Methylation of the pendant pyridyl rings with methyl iodide generates electron-accepting groups covalently attached to the Ru(bipy)3(2+) core.
Redox properties of ground and electronically excited states: [Ru(bpy)2Qbpy]2+ monolayers
Forster, Robert J.,Keyes, Tia E.
, p. 10004 - 10012 (1998)
Dense monolayers of [Ru(bpy)2Qbpy]2+, where bpy is 2,2′-bipyridyl and Qbpy is 2,2′:4,4″:4′4″-quarterpyridyl, have been formed by spontaneous adsorption onto clean platinum microelectrodes. Cyclic voltammetry of these monolayers is nearly ideal, and five redox states are accessible over the potential range from +1.3 to -2.0 V. Chronoamperometry conducted on a microsecond time scale has been used to measure the heterogeneous electron-transfer rate constant, k, for both metal- and ligand-based redox reactions. Heterogeneous electron transfer is characterized by a single unimolecular rate constant (k/s-1). Standard heterogeneous electron-transfer rate constants, k°, have been evaluated by extrapolating Tafel plots of In k vs overpotential, η, to zero driving force to yield values of (5.1 ± 0.3) × 105 s-1, (3.0 ± 0.1) × 106 s-1, and (3.4 ± 0.2) × 106 s-1 for k°3+/2+, k°2+/1+, and k°1+/0, respectively. Temperature-resolved measurements of k reveal that the electrochemical activation enthalpy, ΔH?, decreases from 12.1 ± 1.7 kJ mol-1 for the 3+/2+ reaction to 7.5 ± 0.8 kJ mol-1 for the 2+/1+ process. Probing the temperature dependence of the formal potential gives the reaction entropy, ΔSrc°. Significantly, the free energy of activation is constant at 6.9 ± 0.6 kJ mol-1 for all three redox couples investigated. The electronic transmission coefficient, Kel, describing the probability of electron transfer once the transition state has been reached, is considerably less than unity for all three redox processes. Following photoexitation using a laser pulse at 355 nm, emission is observed from the monolayers with an excited-state lifetime (6.2 μs) that exceeds that of the complex in solution (1.4 μs). It appears that weak electronic coupling between the adsorbates and the electrode means that the excited states are not completely deactivated by radiationless energy transfer to the metal. For the first time, we have used voltammetry conducted at megavolt per second scan rates to directly probe the redox potentials and electron-transfer characteristics of electronically excited species.
An iridium(III)-palladium(II) metal-organic cage for efficient mitochondria-targeted photodynamic therapy
Li, Chaojie,Wang, Yaping,Lu, Yulin,Guo, Jing,Zhu, Chengyi,He, Haozhe,Duan, Xiaohui,Pan, Mei,Su, Chengyong
, p. 1183 - 1187 (2020)
An Ir8Pd4-heteronuclear metal-organic cage (MOC-51) was assembled from bipodal metalloligand [Ir(ppy)2(qpy)(BF4)] (qpy = 4,4′:2′,2″:4″,4?-quaterpyridine; ppy = 2-phenylpridine) with Pd(II) salt. The cubic barrel shaped MOC shows one-photon and two-photon excited deep-red emission, as well as large singlet oxygen quantum yields under visible light irradiation, therefore exhibiting great potentials in organelles-targeted cell imaging and photodynamic therapy (PDT). Compared with the Ir(III) metalloligand, the Ir8Pd4-MOC showed less dark toxicity and higher mitochondria-targeting efficiency. The localization in mitochondria overcomes the limitation of short lifetime and diffusion distance of ROS in cell, thus improved PDT effect can be obtained in low light dose usage of the MOC. This study presents the first case of Ir-based metal-organic cages for bio-applications in successful integration of imaging diagnosis and photodynamic therapy
Phosphorescent soft salt for ratiometric and lifetime imaging of intracellular pH variations
Ma, Yun,Liang, Hua,Zeng, Yi,Yang, Huiran,Ho, Cheuk-Lam,Xu, Wenjuan,Zhao, Qiang,Huang, Wei,Wong, Wai-Yeung
, p. 3338 - 3346 (2016/05/19)
In contrast to traditional short-lived fluorescent probes, long-lived phosphorescent probes based on transition-metal complexes can effectively eliminate unwanted background interference by using time-resolved luminescence imaging techniques, such as photoluminescence lifetime imaging microscopy. Hence, phosphorescent probes have become one of the most attractive candidates for investigating biological events in living systems. However, most of them are based on single emission intensity changes, which might be affected by a variety of intracellular environmental factors. Ratiometric measurement allows simultaneous recording of two separated wavelengths instead of measuring mere intensity changes and thus offers built-in correction for environmental effects. Herein, for the first time, a soft salt based phosphorescent probe has been developed for ratiometric and lifetime imaging of intracellular pH variations in real time. Specifically, a pH sensitive cationic complex (C1) and a pH insensitive anionic complex (A1) are directly connected through electrostatic interaction to form a soft salt based probe (S1), which exhibits a ratiometric phosphorescent response to pH with two well-resolved emission peaks separated by about 150 nm (from 475 to 625 nm). This novel probe was then successfully applied for ratiometric and lifetime imaging of intracellular pH variations. Moreover, quantitative measurements of intracellular pH fluctuations caused by oxidative stress have been performed for S1 based on the pH-dependent calibration curve.
Phosphorescence iridium complex possessing multiple stimulation responding characteristic and application thereof
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Paragraph 0030; 0031; 0032; 0033; 0034, (2017/01/26)
The invention relates to a preparation method for an ionic type transition metal complex containing viologen derivative and application. The ionic type transition metal complex is composed of a cyclometalated ligand and an auxiliary ligand containing a viologen derivative composition, and the structural general formula is shown in the specification. The ionic type transition metal complex is strong in electron capturing capability and good in stimulation responding property, reversible adjusting on luminescence property can be realized by changing the main ligand structure and the alkyl chain structure on the auxiliary ligand. The complex is applicable to high-temperature detection, sensing devices and electroluminescent devices.
