十二烷基磺酸钠-盐酸维拉帕米-联吡啶钌体系电化学发光及其应用

在十二烷基磺酸钠(SDS)中,考察了盐酸维拉帕米-Ru(bpy)3(2+)体系在金电极上的电化学及其发光行为.结果表明:SDS对体系的电化学反应和电化学发光强度具有显著的增敏作用.据此,建立了一种高效、简便的测定盐酸维拉帕米的电化学发光新方法.在最佳实验条件下,盐酸维拉帕米浓度在1.0×10(-4)～1.0×10(-2...     

大尺寸石墨烯量子点组装体的制备及电化学发光性能

对氧化石墨烯纳米材料进行HNO₃氧化处理, 制备了水溶性好且具有强电化学发光(ECL)活性的大尺寸石墨烯量子点组装体(Large-sized graphene quantum dot assemblies, LSGQD-NAs). 利用透射电子显微镜(TEM)、 原子力显微镜(AFM)、 傅里叶变换红外光谱(FTIR)和拉曼光谱(Raman)等方法对其进行了表征, 结果表明, 石墨烯量子点组装体的平均高度为20 nm, 且富含大量的羟基和羧基. 电化学测试结果显示, 在共反应物K₂S₂O₈存在下, LSGQD-NAs在阴极产生很强的ECL(峰值约在685 nm); 并推测了其ECL反应机理, 发现LSGQD-NAs容易通过中心未氧化的石墨烯π-π作用于GC电极表面进行组装修饰. 本研究为基于石墨烯量子点ECL传感器的研究提供了新方法.     

Scanning electrochemical microscopy study of ion annihilation electrogenerated chemiluminescence of rubrene and [Ru(bpy)3]2+

Scanning electrochemical microscopy (SECM) was used for the study of electrogenerated chemiluminescence (ECL) in the radical annihilation mode. The concurrent steady-state generation of radical ions in the microgap formed between a SECM probe and a transparent microsubstrate provides a distance-dependent ECL signal that can provide information about the kinetics, stability, and mechanism of the light emission process. In the present study, the ECL emission from rubrene and [Ru(bpy)(3)](2+) was used to model the system by carrying out experiments with the SECM and light-detecting apparatus inside an inert atmosphere box. We studied the influence of the distance between the two electrodes, d, and the annihilation kinetics on the ECL light emission profiles under steady-state conditions, as well as the ECL profiles when carrying out cyclic voltammetry (CV) at a fixed d. Experimental results are compared to simulated results obtained through commercial finite element method software. The light produced by annihilation of the ions was a function of d; stronger light was observed at smaller d. The distance dependence of the ECL emission allows the construction of light approach curves in a similar fashion as with the tip currents in the feedback mode of SECM. These ECL approach curves provide an additional channel to describe the reaction kinetics that lead to ECL; good agreement was found between the ECL approach curve emission profile and the simulated results for a fast, diffusion-limited second-order annihilation process (k(ann) > 10(7) M(-1) s(-1)). In the CV mode at fixed distance, the ECL emission of rubrene showed two distinct signals at different potentials when fixing the substrate to generate the radical cation and scanning the tip to generate the radical anion. The first signal (pre-emission) corresponded to an emission well before reaching the generation of the radical anion and was more intense on Au than on Pt. The second ECL signal showed the expected steady-state behavior from the second-order annihilation reaction and agreed well with the simulation. A comparison of the emission obtained with rubrene and [Ru(bpy)(3)](2+) to test the direct formation of lower energy triplets directly at the electrode showed that triplets are not the cause of the pre-emission observed. Wavelength selection experiments for the rubrene system showed that the pre-emission ECL signal also appeared slightly red-shifted with respect to the main luminophore emission; a possible explanation for this phenomenon is inverse photoemission, where the injection of highly energetic holes by the oxidized species into the negatively biased tip electrode causes emission of states in the metal that appear at a different wavelength than the singlet emission from the ECL luminophore.     

Electrogenerated chemiluminescence using solution phase and immobilized tris(4,7-diphenyl-1,10-phenanthrolinedisulfonic acid)ruthenium(II)

Electrogenerated chemiluminescence (ECL) with tris(4,7-diphenyl-1,10-phenanthrolinedisulfonic acid)rathenium(II) (RuBPS) in solution and immobilized on an electrode surface is investigated. Flow injection analysis with a thin layer electrochemical cell modified for ECL detection is used to determine the analytical utility of solution phase RuBPS and RuBPS immobilized in a cationic polypyrrole derivative. The solution phase reaction of RuBPS with oxalate is investigated with regard to the dependence of ECL emission on RuBPS concentration, carrier stream flow rate, and pH. In the parameter range studied, ECL intensity is not linear with the concentration of RuBPS in the sample. A maximum ECL intensity is observed with a RuBPS concentration of approximately 250 M. Slower linear velocities give greater ECL intensities which is the opposite of what is observed for Ru(bpy) ₃ ³⁺ and oxalate. Greater ECL intensity is observed at lower pHs for oxalate and at higher pHs for proline. RuBPS ECL with oxalate yields a working curve with a linear range from 0.1–100 M oxalate. Solution phase ECL is observed for RuBPS and other amines such as NADH, proline, tripropylamine, and antibiotics including streptomycin and gentamicin. RuBPS is also immobilized by electrochemical polymerization of 1-methyl-3-(pyrrol-1-ylmethyl)pyridinium chloride (MPP) in the presence of RuBPS. This polymer-modified electrode yields ECL for oxalate and for amines.Deceased     

A novel electrogenerated chemiluminescence sensor for pyrogallol with core-shell luminol-doped silica nanoparticles modified electrode by the self-assembled technique

The core-shell luminol-doped SiO₂ nanoparticles were synthesized and immobilized on the surface of chitosan film coating graphite electrode by the self-assembled technique. Then, a novel electrogenerated chemiluminescence (ECL) sensor for pyrogallol was developed based on its ECL enhancing effect for the core-shell luminol-doped silica nanoparticles. The ECL analytical performances and the sensing mechanism of this ECL sensor for pyrogallol were investigated in detail. The corresponding results showed that: compared with the conventional ECL reaction procedures by luminol ECL reaction system, the electrochemical (EC) reaction of pyrogallol and its subsequent chemiluminescence (CL) reaction occurred in the different spatial region whilst offering a high efficiency to couple the EC with the CL reaction to form the ECL procedures. In this case, this new sensing scheme offered more potential to improve the analytical performances of the ECL reaction. Under the optimum experimental conditions, this ECL sensor showed less than 5% decrease in continuums over 100 times ECL measurements, the detection limit was 1.0 × 1.0⁻⁹ mol/L for pyrogallol. The linear range extended from 3.0 × 10⁻⁹ mol/L to 2.0 × 10⁻⁵ mol/L for pyrogallol.     

Electrogenerated chemiluminescence of luminol on a gold-nanorod-modified gold electrode

Electrogenerated chemiluminescence (ECL) of luminol on a gold-nanorod-modified gold electrode was studied, and five ECL peaks were obtained under conventional cyclic voltammetry in both neutral and alkaline solutions. Among them, four ECL peaks (ECL-1-4) were also observed on a gold-nanosphere-modified gold electrode, but the intensities of these ECL peaks were enhanced about 2-10-fold on a gold-nanorod-modified gold electrode in neutral solution. One new strong ECL peak (ECL-5) was obtained at -0.28 V (vs SCE) on a gold-nanorod-modified gold electrode in both neutral and alkaline solutions and enhanced with an increase in pH. In strong alkaline solutions, ECL-1 and ECL-2 on a gold-nanosphere-modified electrode were much stronger than those on a gold-nanorod-modified gold electrode, while ECL-3-5 appeared to only happen on a gold-nanorod-modified gold electrode. The emitter of all the ECL peaks was identified as 3-aminophthalate. The ECL peaks were found to depend on the scan direction, the electrolytes, the pH, and the presence of O(2) and N(2). The reaction pathways for ECL-4 have been further elucidated, and the mechanism of the new ECL peak (ECL-5) has been proposed. The results indicate that a gold-nanorod-modified gold electrode has a catalytic effect on luminol ECL different from that of a gold-nanosphere-modified gold electrode, revealing that the shape of the metal nanoparticles has an important effect on the luminol ECL behavior. The strong ECL of luminol in neutral solution obtained on a gold-nanorod-modified electrode may be used for the sensitive detection of biologically important compounds in physiological conditions.     

Electrochemiluminescence Behavior of Ru(bpy)32+/Carbofuran System on an Electrically Heated Microelectrode Chip

An electrically heated microelectrode chip (HMEC) was designed and the Ru(bpy)₃²⁺/carbofuran electrochemiluminescence (ECL) systems were applied to characterize the performance of the HMEC. The ECL intensities increase at elevated electrode temperature, and the detection limit at 60°C (electrode surface temperature) was about 10 times lower than that at 30°C. The results indicate that new heated electrode can be handled easily and can be mass produced, the difference between the electrodes was little. The stability of the HMEC was good since the electrode surface can hardly be destroyed during detection and storage.     

The electrochemiluminescent behavior of nickel phthalocyanine（NiTSPc）/H2O2 system on a heated ITO electrode

In this study,the electrochemiluminescent（ECL） behavior of Nickel（Ⅱ） tetrasulfophthalocyanine（NiTSPc）/H₂O₂ on a heated indium tin oxide（ITO） electrode was investigated.The effect of pH value,electrochemical scan mode,concentration of NiTSPc and electrode surface temperature on the ECL intensities had been studied in detail.Based on the fact that the ECL of NiTSPc can be greatly enhanced by hydrogen peroxide at the ITO electrode,a new ECL biosensor for hydrogen peroxide has been developed.The possible mechanism for the ECL of NiTSPc has also been proposed.     

Ligand and surfactant effects on a novel electrochemiluminescent reaction involving cadmium

Electrochemiluminescence (ECL) is the generation of light during a chemical reaction with at least one of the reagents being generated in situ at an electrode. Recently, a host of methods have been developed employing ECL reactions as an analytical technique where one of the ECL reagents is the analyte. Electrochemiluminescent reactions involving aqueous metal ions can offer an alternative method for quantitation of dissolved metals. Previous work developed an ECL system using 1,10-phenanthroline as an ECL reagent in conjunction with Cd²⁺ ions providing sufficient emission for reliable cadmium detection. This paper explores the effects of ligand modification, choice of surfactant, and the interaction between the surfactant and the co-reactant tripropylamine (TPA). The effectiveness of the reagents tested can be ranked as phenanthroline, bathophenanthroline salt, terpyridine, dimethylphenanthroline, and bipyridine in order of decreasing Cd²⁺ specific ECL emissions. The non-ionic surfactants Triton X-100, Thesit, and Nonidet P40 were surveyed.     

十二烷基苯磺酸钠-盐酸苯海索-Ru(bpy)2+3体系的电化学发光行为研究及应用

在十二烷基苯磺酸钠(SDBS)存在下,考察了盐酸苯海索(BH)-Ru(bpy)32+体系的电化学及其发光行为。结果表明,BH对Ru(bpy)32+体系的电化学发光具有增敏效应;在SDBS存在下,BH对Ru(bpy)32+体系电化学发光的增敏效应显著增强,发光强度提高约16倍。据此建立了一种高效、简便的BH电化学发光新方法。在最佳实验条件下,BH的浓度在4.0×10-7～1.0×10-4 mol/L范围内与相对发光强度呈线性关系(r=0.995 5),检出限(S/N=3)为1.11×10-9 mol/L;连续平行测定1.0×10-5 mol/L BH溶液10次,发光强度的RSD为3.2%。样品的回收率为96%～108%,RSD为4.3%。该方法样品前处理简单,具有较高的选择性和灵敏度,用于实际样品中BH的测定,结果满意。     

Transparent Carbon Nanotube Network for Efficient Electrochemiluminescence Devices

A carbon nanotube‐based electrode that combines transparency and good conductivity was used for the first time to develop an electrochemiluminescence (ECL) device. It resulted in an excellent material for ECL applications thanks to the very favorable overpotential of amine oxidation that represents the rate‐determining step for the signal generation in both research systems and commercial instrumentation. The use of carbon nanotubes resulted in a ten times higher emission efficiency compared with commercial transparent indium tin oxide (ITO) electrodes. Moreover, application of this material for proof‐of‐principle ECL imaging was demonstrated, in which micro‐beads were used to mimic a real biological sample in order to prove the possibility of obtaining single cell visualization.     

Electrochemiluminescence Characterization of Poly(luminol‐benzidine) Composite Films and Their Analytical Application

A composite film of poly(luminol‐benzidine) was prepared on the graphite electrode surface by electropolymerizing luminol and benzidine in acidic medium. It was found that the poly(luminol‐benzidine) composite film presented better electrochemiluminescence (ECL) analytical performances for H₂O₂ than that of the polyluminol film. Based on these findings, a more sensitive ECL sensor for H₂O₂ was developed. At the same time, our investigating results on this composite film revealed that, as a real ECL luminophor in this composite film, the polymeric 3‐aminophthalate presented higher fluorescence quantum yield than that in the pure polyluminol film, which suggested that the excellent ECL performances of the composite film may originate from the enhancement of the ECL luminophor quantum yield. Based on these results, a new method to improve the ECL analytical performances of the polymeric luminol was also proposed.     

Efficient and Monochromatic Electrochemiluminescence of Aqueous‐Soluble Au Nanoclusters via Host–Guest Recognition

Inspired by the enhanced photoluminescence of Au nanoclusters (AuNCs) with a rigid shell, the formation of rigid host–guest assemblies on AuNC surfaces was employed to screen novel electrochemiluminophores with 6‐aza‐2‐thiothymine(ATT)‐protected AuNCs (ATT‐AuNCs) and l ‐arginine (ARG) as models for the first time. The rigid host–guest assemblies formed between ARG and ATT on the ATT‐AuNC surface enabled aqueous‐soluble ARG/ATT‐AuNCs with a dramatically enhanced electrochemiluminescence (ECL) compared to ATT‐AuNCs. This includes one cathodic ECL process (?1.30 V) and three anodic ECL processes (+0.78, 0.90, and 1.05 V) in a so‐called half‐scan experiment without a co‐reactant, as well as a 70‐fold enhanced oxidative‐reduction ECL at +0.78 V with tri‐n‐propylamine as a co‐reactant. Importantly, the ECL of the ARG/ATT‐AuNCs is highly monochromatic with an emission maximum around 532 nm and a full width at half‐maximum of 36 nm, which is of great interest for color‐selective ECL assays.     

磺基水杨酸修饰电极联吡啶钌电化学发光体系测定可待因的研究

基于磷酸可待因对联吡啶钌在该电极上的电化学及其发光行为的增敏作用,建立了一种直接测定磷酸可待因的电化学发光新方法。在最佳实验条件下,磷酸可待因在1.0×10-4～4.0×10-6mol/L和4.0×10-6～2.0×10-7mol/L与相对发光强度呈线性关系,检出限为1.0×10-7mol/L(S/N=3)。连续测定4.0×10-7mol/l磷酸可待因5次,发光强度的RSD为2.7%。方法用于模拟尿样中磷酸可待因的测定,结果满意。     

Analytical applications of electrochemiluminescence: an overview

The chemical transformations of electrogenerated ion-radicals of a number of complex organic compounds may be accompanied by emission of photons. An electrochemiluminescence (ECL) quantum contains information both on the kinetics of the heterogeneous electrode processes and on the subsequent homogeneous chemical reactions in the solution. Application of ECL to solution analysis provides advantages in comparison to electrochemical methods. Using ECL for electrode surface analysis allows information to be obtained on the rate of an electrochemical process simultaneously at all points of the electrode under analysis in real time, and that is the main difference between this method and the point-by-point testing specific to electrochemical methods. The potential of ECL for analytical chemistry is examined concerning the homogeneous ECL-analysis of solutions and the heterogeneous ECL-analysis of electrode surfaces. Received: 6 April 2000 / Revised: 23 June 2000 / Accepted: 27 June 2000     

基于碳纳米管修饰电极的胆碱电化学发光生物传感器研制

在碳纳米管(CNTs)和K3Fe(CN)6修饰的铂电极上吸附固定胆碱氧化酶,以鲁米诺为发光试剂,研制了胆碱电化学发光(ECL)生物传感器。CNTs可有效提高电极表面的电荷传输能力、提高电极表面的生物相容性和对酶分子的固载能力;K3Fe(CN)6对酶活性具有激活作用,同时对H2O2增敏的鲁米诺ECL有增强作用,均有利于提高传感器的检测灵敏度。研究表明,将CNTs分散液与K3Fe(CN)6混合,滴涂修饰在Pt电极上,吸附固定胆碱氧化酶,制备传感器。此传感器在含有8×10-6mol/L鲁米诺的磷酸盐缓冲液(pH7.4)、30℃条件下产生的ECL强度与胆碱浓度在1×10-7～4×10-3mol/L范围内呈线性关系,相关系数为0.994,检出限为1.2×10-8 mol/L。此生物传感器应用于鼠血样中胆碱的测定,测得结果为2.68 mg/L,平均回收率为101.1%。传感器具有快速、稳定和重现性好等特点,有望应用于常规分析。     

Electrochemiluminescence of SDBS‐Ru(bpy)32+‐CPM System and Its Application

When the concentration of dodecyl benzene sulfonic acid sodium salt (SDBS) is 0.7 mmol·L^?1, the electrochemical and electrochemiluminescence (ECL) intensity of Ru(bpy)₃²⁺‐chlorpheniramine maleate (CPM) system at the Au electrode were studied. The results showed that compared with the absence of SDBS, enhancement of the ECL intensity was 14‐fold at Au electrode. Base on this, an ECL method was established for efficient and simple determination of CPM at Au electrode. Under the optimum experimental condition, the enhanced ECL intensities had good linear relationship with the concentration of CPM in the range of 1.0×10^?4–1.0×10^?7 mol·L^?1, and a linear regression equation was obtained as follows: I (counts)=48.805×10⁶c+394.03 (r=0.9975), the detection limit for CPM was 1.4×10^?8 mol·L^?1. The RSD for 5 times determinations of 1.0×10^?5 mol·L^?1 CPM was 3.2%. The results of recovery test were between 96.3%–102.5%, and the RSD of recovery test (n=5) was 2.7%. In addition, eleven kinds of tertiary amines‐Ru(bpy)₃²⁺ systems were investigated in the absence and presence of SDBS. The results showed that the enhancement of SDBS on ECL intensity of tertiary amines‐Ru(bpy)₃²⁺ systems was universal.     

Electrogenerated Chemiluminescence (ECL) Determination of Ephedrine with a Self-Assembly Multilayer Ni(II)-Polyluminol Modified Electrode

By combining the layer-by-layer (LBL) self-assembly technique with the electrochemical polymerization method, multilayer Ni(II)-polyluminol films were modified on the surface of a vaseline-impregnated graphite electrode. It was found that, compared with an electrode modified by direct electrochemical polymerization, this modified electrode offered a suitable ECL reaction micro-environment created by the special multilayer films, which was beneficial to the ephedrine hydrochloride enhancing effect for luminol ECL intensity. The ECL enhancing effect of ephedrine hydrochloride on the electro-oxidation luminol was improved on this modified electrode. Based on this finding, a new sensitive ECL method was developed for ephedrine hydrochloride determination under the optimal conditions. At the same time, a new idea is proposed for improving the analytical performance of the luminol ECL system by modifying the ECL reaction micro-environment with the layer-by-layer self- assembly method. Under the optimum experimental conditions, the ephedrine hydrochloride concentration in the range of 2.0 × 10⁻⁸–7.0 × 10⁻⁶ mol L⁻¹ was proportional to the enhanced ECL signal, and it offered an 8.0 × 10⁻⁹ mol L⁻¹ detection limit for ephedrine hydrochloride.     

Comparative study of ruthenium(II) tris(bipyridine) derivatives for electrochemiluminescence application

Several [Ru(bpy)3]2+ (bpy = 2,2'-bipyridine and its derivatives) complexes were synthesized and compared electrochemically and spectroscopically in the search for better luminophores for electrochemiluminescence (ECL)-based analytical applications. ECL measurement in [Ru(bpy)3]2+/tripropylamine (TPA) aqueous buffer solutions has led to a conclusion that due to the complexity of the ECL generation process, the photoluminescence efficiency cannot be used to predict ECL intensity and there is no obvious relationship between the photoluminescence quantum yield and the ECL intensity. Under the present experimental condition, when compared with the pristine [Ru(bpy)3]2+, the ethoxycarbonyl-substituted derivative, [Ru(bpy-COOEt)3]2+, one of the most efficient luminophores under photoexcitation, did not generate reasonably intense ECL, whereas luminophores with lower photoluminescence quantum yields demonstrated higher ECL. These findings are useful for further efforts in the search for more efficient ECL luminophores.     

聚鲁米诺-金属离子复合物膜的电化学发光特性及其分析应用研究

建立了一种基于电聚合和配位效应构建聚鲁米诺-金属离子复合物膜修饰电极测定尿素的电化学发光分析新方法, 并且提出了一种优化聚鲁米诺电化学发光分析特性的新思路. 在最佳条件下, 增敏电化学发光信号与尿素的质量浓度在2.0×10-9—1.0×10-7 g/mL 范围内呈线性关系, 检出限为1.7×10-10 g/mL.