一种新型联吡啶钌配合物的电致化学发光性能

合成了一种多联吡啶钌配合物(bpy)2Ru(phenCl4)(PF6)2,bpy为2,2′-联吡啶,phenCl4为3,4,7,8-四氯-1,10-邻菲罗啉,并用元素分析、红外光谱、核磁共振谱测试技术对结构进行了表征. 化合物在紫外和可见光区均有吸收,在可见光区的最大吸收波长为440 nm,这是典型的金属到配体(MLCT)的跃迁,其光致发光性能也显示出MLCT迁移特征,并且随溶剂不同,其最大发射波长从630 nm变化至649 nm. 配合物的电致化学发光性能受pH值影响不大,与随pH值增大电致化学发光强度增大的联吡啶钌不同,尤其在强碱条件下,其背景电致化学发光很小.     

联吡啶钌修饰电极固相电致化学发光

由于电致化学发光(ECL)的连续可测性、高灵敏度、稳定和方法简单,被广泛应用于分子生物学、药学、化学和环保等领域.而将可电化学再生的ECL试剂固定于电极表面,可获得ECL传感器,从而减少分析过程中试剂的消耗并简化实验装置.联吡啶钌及其衍生物在电极表面的固定化研究成为ECL研究的重要方向.本文综述了2004年以来联吡啶钌及其衍生物修饰电极的固相ECL的研究进展,并简要介绍了各种固定方法及其相关的应用情况.     

金属离子对联吡啶钌电致化学发光影响的研究

在玻碳电极上, 联吡啶钌[Ru(bpy)₃^2＋]于＋1.50 V (vs. Ag/AgCl)左右被氧化为Ru(bpy)₃^3＋, 该氧化态离子与碱性水溶液中(pH 8.2)的OH•反应生成激发态的[Ru(bpy)₃^2＋*]而发光. 研究比较了15种金属离子对Ru(bpy)₃^2＋碱性水溶液电致化学发光的影响, 并对这些影响进行了初步的解释.     

槐定碱-联吡啶钌电致化学发光的研究

研究了槐定碱在碱性联吡啶钌(Ru(bpy)32 )水溶液(pH 9.0)中电致化学发光行为。在玻碳电极上,槐定碱中的氨基氮于 1.30 V(vs.Ag/AgCl)左右被氧化为氮正自由基离子,该自由基离子与Ru(bpy)32 反应生成激发态的Ru(bpy)32 *而发光。利用原位在线电致化学发光方法,槐定碱的检出限为1.0×10-10g/mL。     

基于MCM-41负载联吡啶钌的电致化学发光传感器

利用静电吸附作用将联吡啶钌[Ru(bpy)₃²⁺]负载到巯基化MCM-41介孔二氧化硅纳米颗粒上, 通过金-巯键修饰法将负载后的MCM-41固定在金电极表面, 发展了一种基于MCM-41负载联吡啶钌的电致化学发光传感器, 并研究了其电化学及电致化学发光行为. 基于三聚氰胺与增敏剂三正丙胺氨基结构的相似性, 将负载Ru(bpy)₃²⁺的MCM-41电致化学发光传感器用于三聚氰胺的检测, 获得了良好的检测效果, 为检测三聚氰胺提供了一种快速、简便的方法. 同时, 该研究为Ru(bpy)₃²⁺在电极表面的固定化提供了新思路.     

硅量子点为共反应剂的联吡啶钌电致化学发光研究及对多巴胺的检测

利用水热法合成了水溶性硅量子点(SiQDs),并探究了联呲啶钌(Ru(bpy)23-)在硅量子点修饰玻碳电极(SiQDs/GCE)上的电致化学发光(ECL)行为.结果表明,在中性条件下,SiQDs能够作为共反应剂明显增强Ru(bpy)32+的阳极ECL信号.研究了SiQDs修饰量、缓冲溶液pH等因素对该体系ECL信号的...     

联吡啶钌-草酸体系电致化学发光猝灭法检测苯胺和联苯胺

利用苯胺和联苯胺对联吡啶钌 草酸体系电致化学发光的强猝灭作用 ,建立了电致化学发光猝灭的流动注射检测苯胺和联苯胺的方法。该方法具有良好的重现性和稳定性。在所选定的实验条件下 ,苯胺和联苯胺的检出限分别为 5 .0× 10 -7mol/L和 2 .0× 10 -7mol/L。对 1.0× 10 -5mol/L的苯胺和联苯胺 ,测定的标准偏差分别为 3%和 2 .5 % (n =6 )。对苯胺和联苯胺对联吡啶钌 草酸体系电致化学发光的猝灭机理进行了初步的探讨。     

毛细管电泳-电致化学发光测定诺氟沙星的研究

基于诺氟沙星对联吡啶钌在铂电极上的电致发光信号有增敏作用，与毛细管电泳结合，建立了一种测定诺氟沙星的电化学发光分析新方法。研究了工作电极电位、磷酸盐缓冲液浓度及其pH值、进样电压和进样时间等实验参数对诺氟沙星测定的影响。在优化的实验条件下，其浓度线性范围为0．02～10μmol／L；检出限（3σ）为0.0048μmol／L；峰面积的相对标准偏差为2．6％（1．0μmol／L，n=11）。本法可直接用于尿液中诺氟沙星（NFLX）含量的测定。回收率为92．7％～97．9％，结果满意。     

某些含氮神经药物的流动注射联吡啶钌电致化学发光研究

利用联吡啶钌 [Ru(bpy) 3Cl2 ]对几种胺类神经药物的电致化学发光 (ECL)流动注射分析进行了研究。使用改进的流动电解池 ,建立了原位在线的ECL方法 ,提高了检测的灵敏度。在浓度为 0 .0 5mol L的磷酸盐缓冲溶液 (pH =9.0 )中 ,甲基安非它明 (METH)的ECL最强。发光强度与浓度在 6.8× 1 0 - 1 1 ～ 6.8× 1 0 - 3mol L范围内具有良好的线性 ,检出限达 2× 1 0 - 1 6 mol/L ,优越于一般的检测方法 ;比较了METH与安非它明 (APM)的电致化学发光 ;研究了可待因、可卡因、吗啡和咖啡因等毒品的ECL行为 ,并利用循环伏安法对它们不同的发光强度进行了分析。实验结果表明 :该系统简单、方便 ,测定灵敏度高 ,尤其是不需要过氧化物 ,能更方便应用于流动分析体系 ,并为刑侦破案提供了一定的依据。     

一系列Ru(II)配合物电致化学发光性质的比较研究

比较研究了以C₂O₄^2－为共反应物时5个结构相关的Ru(II)配合物[Ru(bpy)₂L¹]^2＋, [Ru(bpy)₂L²]^2＋, [Ru(bpy)₂L³]^2＋, [Ru(phen)₂L¹]^2＋和[Ru(phen)₂L²]^2＋(其中bpy＝2,2′-联吡啶, phen＝1,10-邻菲啰啉, L¹＝4-羧基苯基咪唑[4,5-f][1,10]邻菲啰啉, L²＝3-羧基-4-羟基苯基咪唑[4,5-f][1,10]邻菲啰啉, L³＝3,4-二羟基苯基咪唑[4,5-f][1,10]邻菲啰啉)的电致化学发光(ECL)性质. 结果表明, 酚羟基的存在能有效地淬灭Ru(II)配合物[Ru(bpy)₂L²]^2＋, [Ru(bpy)₂L³]^2＋和[Ru(phen)₂L²]^2＋的ECL, 其它Ru(II)配合物的ECL量子效率与[Ru(bpy)₃]^2＋相差不大.     

Photoluminescent and electrochemiluminescent dual-signaling probe for bio-thiols based on a ruthenium(II) complex

Photoluminescence (PL) and electrochemiluminescence (ECL) detection techniques are highly sensitive and widely used methods for clinical diagnostics and analytical biotechnology. In this work, a unique ruthenium(II) complex, [Ru(bpy)₂(DNBSO-bpy)](PF₆)₂ (bpy: 2,2′-bipyridine; DNBSO-bpy: 2,4-dinitrobenzenesulfonate of 4-(4-hydroxyphenyl)-2,2′-bipyridine), has been designed and synthesized as a highly sensitive and selective PL and ECL dual-signaling probe for the recognition and detection of bio-thiols in aqueous media. As a thiol-responsive probe, the complex can specifically and rapidly react with bio-thiols in aqueous solutions to yield a bipyridine-Ru(II) complex derivative, [Ru(bpy)₂(HP-bpy)]²⁺ (HP-bpy: 4-(4-hydroxyphenyl)-2,2′-bipyridine), accompanied by the remarkable PL and ECL enhancements. The complex was used as a probe for the PL and ECL detections of cysteine (Cys) and glutathione (GSH) in aqueous solutions. The dose-dependent PL and ECL enhancements showed good linear relationships against the Cys/GSH concentrations with the detection limits at nano-molar concentration level. Moreover, the complex-loaded HeLa cells were prepared for PL imaging of the endogenous intracellular thiols. The results demonstrated the practical utility of the complex as a cell-membrane permeable probe for PL imaging detection of bio-thiols in living cells.     

Immobilization of tris(1,10-phenanthroline)ruthenium with graphene oxide for electrochemiluminescent analysis

Electrochemiluminescence (ECL) of ruthenium complexes has broad applications and the immobilization of Ru(bpy)₃²⁺ has received extensive attention. In comparison with Ru(bpy)₃²⁺, Ru(phen)₃²⁺ can be immobilized more easily because of its better adsorbability. In this study, immobilization of Ru(phen)₃²⁺ for ECL analysis has been demonstrated for the first time by using graphene oxide (GO) as an immobilization matrix. The immobilization of Ru(phen)₃²⁺ is achieved easily by mixing Ru(phen)₃²⁺ with GO without using any ion exchange polymer or covalent method. The strong binding of Ru(phen)₃²⁺ with GO is attributed to both the π–π stacking interaction and the electrostatic interaction. The Ru(phen)₃²⁺/GO modified electrode was characterized by using tripropylamine (TPA) as the coreactant. The linear range of TPA is from 3 × 10⁻⁷ to 3 × 10⁻² mol L⁻¹ with the detection limit of 3 × 10⁻⁷ mol L⁻¹. The ECL sensor demonstrates outstanding long-term stability. After the storage in the ambient environment for 90 days, the ECL response remains comparable with its original signal.     

DNA interaction studies of ruthenium(II) polypyridyl complex : [Ru(dmb)2(ITAP)](ClO4)2 (ITAP = isatino [1,2-b]-1,4,8,9-tetraazatriphenylene)

A new ligand ITAP and its complex [Ru(dmb)₂(ITAP)](ClO₄)₂ (ITAP = isatino [1,2-b]-1,4,8, 9-tetraazatriphenylene, dmb = 4,4′-dimethyl-2,2′-bipyridine) have been synthesized and characterized by elemental analysis, Fast atom bombardment mass spectra, Electrospray mass spectra, and ¹H NMR. Thermal denaturation and absorption titration experiments show the complex binds to calf thymus DNA (CT-DNA) with moderate affinities. Viscosity measurements and thermal denaturation indicate that the DNA-binding mode could be intercalative interaction. The Ru(II) complex in the presence of plasmid pBR322 DNA has been found to promote the cleavage of plasmid pBR322 DNA from the supercoiled Form I to the open circular Form II upon irradiation. Mechanisms for DNA cleavage by the complex were also investigated.     

Synthesis and characterization of electrochemiluminescent ruthenium(II) complexes containing o-phenanthroline and various alpha-diimine ligands

A series of o-phenanthroline-substituted ruthenium(II) complexes containing 2,2′-dipyridyl, 2-(2-pyridyl)benzimidazole, 2-(2-pyridyl)-N-methylbenzimidazole, 4-carboxymethyl-4′-methyl-2,2′-dipyridyl, and/or 4,4′-dimethyl-2,2′-dipyridyl ligands were synthesized and examined as potent electrochemiluminescent (ECL) materials. The characteristics of these complexes, regarding their electrochemical redox potentials and relative ECL intensities for tripropylamine were studied. As found in a 2,2′-bipyridyl-substituted ruthenium(II) complexes, a good correlation between the observed ECL intensity and the donor ability of α-diimine ligands was observed, i.e., the ECL intensity of the Ru(II) complex decreased with an increase in the ligand donor ability. The ECL efficiency increased as the number of substitutions of o-phenanthroline (o-phen) to metal complexes increased.     

Synthesis and characterization of a mononuclear ruthenium(III) triazole complex

A mononuclear ruthenium(III) complex containing ethylenediaminetetraacetate (edta), [Ru(Hedta)(Htrz)] · 4H₂O (1) (Htrz = 1H-1,2,4-triazole), has been synthesized and the structure was determined by single-crystal X-ray diffraction. The complex crystallizes in the triclinic space group P 1, with the unit cell parameters a = 7.212(3) Å, b = 9.873(4) Å, c = 13.806(6) Å, α = 91.945(6)°, β = 100.078(6)°, γ = 97.230(7) and Z = 2. The complex was also characterized by elemental analysis, IR, UV–Vis and ESR spectra. Cyclic voltammetry for the complex shows a ruthenium(III)/ruthenium(IV) oxidation and a ruthenium(III)/ruthenium(II) reduction within the range of ?1.5–0.5 V. Magnetic susceptibility data give an effective moment of 1.81 B.M. at room temperature.     

Star-shaped electrochemiluminescent metallodendrimers with central polypyridyl Ru(II) complexes: Synthesis and their photophysical and electrochemical properties

Several dendritic bridging ligands were designed and synthesized to develop more sensitive and efficient electrochemiluminescent (ECL) polynuclear Ru(II) complexes. Various types of novel two-armed, four-armed and six-armed tris(bipyridyl)ruthenium core dendrimers were synthesized by coordinating dendritic polybipyridyl ligands with Ru(II) complexes, and the effect of the ligand and the dendritic network on the ECL characteristics were studied. Their electrochemical redox potentials, UV, photoluminescence (PL), and relative ECL intensities were also investigated in detail. The synthesized metallodendrimers exhibited strong metal-to-ligand charge transfer (MLCT) absorption at 428-451 nm and emission at 591-601 nm. Most of the newly synthesized metallodendrimers showed enhanced ECL intensities compared to the reference complex, [Ru(o-phen)₃](PF₆)₂. In particular, the ECL intensities of the six-armed heptanuclear ruthenium complexes were almost four times greater than that of [Ru(o-phen)₃]²⁺. These metallodendrimers could be utilized as efficient ECL materials and light emitting devices.     

A fluorescent chemosensor for cobalt ions based on a multi-substituted phenol-ruthenium(II) tris(bipyridine) complex

An amide-linked 2,6-bis{[(2-hydroxy-5-tert-butylbenzyl)(pyridyl-2-methyl)-amino]-methyl}-4-methylphenol-ruthenium(II) tris(bipyridine) 2PF₆⁻ complex, 1, was first used to recognize Co(II) in EtOH/H₂O (1:1, v/v) solution, with the ruthenium(II) tris(bipyridine) moiety selected as a fluorophore and the multi-substituted phenol unit chosen as a receptor. The fluorescence quenching of 1 was attributed to the formation of an inclusion complex between multi-substituted phenol unit and Co(II) by 1:1 complex ratio (K = 2.5 × 10⁵), which has been utilized as the basis of the fabrication of the Co(II)-sensitive fluorescent chemosensor. The analytical performance characteristics of the proposed Co(II)-sensitive chemosensor were investigated. The sensor can be applied to the quantification of Co(II) with a linear range covering from 1.0 × 10⁻⁷ to 5.0 × 10⁻⁵ M and a detection limit of 5 × 10⁻⁸ M. The experiment results show that the response behavior of 1 to Co(II) is pH-independent in medium condition (pH 4.5–9.5) and show excellent selectivity for Co(II) over transition metal cations except Cu(II). The chemosensor has been used for determination of Co(II) in water samples.     

Luminescence and oxygen sensing properties of ORMOSILs covalently grafted with a novel ruthenium(II) complex

A series of VTES/TEOS composite xerogels covalently grafted with a novel complex Ru(phen)₂(Dppz-Si)Cl₂ were prepared, using the alkoxysilane-modified dipyrido[3,2-a:2′,3′-c]phenazine compound (denoted as Dppz-Si) as the second ligand of the Ru(phen)₂Cl₂ (phen = 1,10-phenanthroline) complex and a precursor of the sol–gel process. Bulk xerogels were obtained by co-hydrolyzing and co-condensation from a mixture of triethoxysilane (TEOS), Ru(phen)₂(Dppz-Si)Cl₂ and Vinyltriethoxysilane (VTES). The luminescence intensity of composite xerogels is enhanced by 18.2 times, and the sensitivity is improved from 1.1 to 3.1 by optimizing the molar ratio of VTES to TEOS. The composite xerogel containing 80% VTES in precursor was optimal, exhibiting the maximum luminescence intensity and sensitivity. These results indicate that the complex Ru(phen)₂(Dppz-Si)Cl₂ is sensitive to oxygen concentration, VTES is a kind of excellent organic modifier and can greatly improved photoluminescent (PL) and oxygen sensing performances.