首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 158 毫秒
1.
研究了苦豆子中主要生物碱槐定碱、苦参碱,以及神经兴奋药物甲基安非他命 、安非他命等化合物,在碱性联吡啶钌[Ru(bpy)_3~(2+)]水溶液(pH 9.0)中的电 致化学发光(ECL)行为。在玻碳电极上,生物碱中的氨基氮于+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)_3~(2+)反应生 成激发态的Ru(bpy)_3~(2+*)而发光。研究比较了取代基性质、氨基氮周围的三维 空间结构对各生物碱ECL的影响,并结合生物碱氨基氮的电离势和键角的计算,对 这些影响进行了解释。  相似文献   

2.
研究了CdS量子点(CdS QDs)对三联吡啶钌(Ru(bpy)_3~(2+))电致化学发光(ECL)信号的作用,发现CdS QDs对Ru(bpy)_3~(2+)的ECL信号有良好的增敏作用,基于此建立了高灵敏的CdS QDs/Ru(bpy)_3~(2+)ECL体系。探讨了该体系的ECL机理,考察了CdS QDs的浓度、缓冲溶液p H值、扫描速率等实验参数对ECL信号的影响,优化了体系的ECL条件。基于邻苯二酚对该体系ECL信号的抑制作用,建立了邻苯二酚的ECL检测方法。在1.0×10~(-8)~1.0×10~(-5)mol/L范围内,邻苯二酚的浓度与ECL信号的变化值呈良好的线性关系,检出限(S/N=3)为5.5 nmol/L,将本方法用于茶叶中邻苯二酚的检测,结果令人满意。  相似文献   

3.
采用简单的方法合成了氮掺杂石墨烯量子点(NG QDs),并分别用荧光光谱仪和透射电子显微镜进行了表征。研究了NG QDs对Ru(bpy)_3~(2+)电致化学发光(ECL)体系的增敏作用。实验优化了体系pH、Ru(bpy)_3~(2+)用量、NG QDs用量以及扫速等条件。在最优条件下,根据邻苯二酚对NG QDs/Ru(bpy)_3~(2+)耦合ECL体系信号的猝灭作用,建立了测定邻苯二酚的新方法。邻苯二酚浓度(1.0×10~(-8)~1.0×10~(-5) mol/L)的对数值与ECL信号强度差之间呈线性关系,检测限低至5.0×10~(-9) mol/L,而且选择性和重现性好,实际样品检测结果令人满意。  相似文献   

4.
Ru(bpy)_(3~(2 )) electrochemiluminescence (ECL) was applied to determination of rutin. ECL intensity of Ru(bpy)_(3~(2 ))could be enhanced in the presence of rutin in basic solution on platinum electrode. At pH 9.9, light emission intensity was found to be linear with rutin in the range of 1-50 mmol/L.  相似文献   

5.
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。  相似文献   

6.
依据多壁碳纳米管(MWNT)导电性优良和纳米银(nano-Ag)电催化特性,以硅溶胶(silica sol)为成膜剂,在助膜剂聚乙烯醇(PVA)协同作用下,以溶胶-凝胶法实现了对MWNT、nano-Ag及Ru(bpy)_3~(2+)在热解石墨电极表面的固载修饰,制备出MWNT/nano-Ag/silica sol/PVA/Ru(bpy)_3~(2+)修饰热解石墨电极,并依据苦参碱(MT)对Ru(bpy)_3~(2+)增敏作用,建立了电致化学发光法对苦参碱的测定方法。结果表明,苦参碱浓度在2. 04×10~(-7)~1. 02×10~(-4)mol/L范围内与Ru(bpy)_3~(2+)-MT体系ECL强度呈良好线性关系(R~2=0. 998),检出限(S/N=3)为2. 96×10~(-9)mol/L,连续平行测定1. 02×10~(-5)mol/L苦参碱溶液5次,ECL强度的相对标准偏差(RSD)为1. 3%,体系稳定性及重现性良好; 3组样品平均加标回收率为97. 7%~103. 9%。  相似文献   

7.
联吡啶钌(Ru(bpy)2+3)是应用最广泛的电致化学发光(ECL)活性物。将可电化学再生的Ru(bpy)2+3及其类衍生物固定于电极表面,获得固相ECL传感器是ECL研究的重要方向之一。本文综述了Ru(bpy)2+3及其衍生物固相ECL近年来的研究进展,简要介绍不同固定化技术及其应用情况。  相似文献   

8.
在过去的十年内,过渡金属联吡啶配合物的光物理和光化学过程得到了迅速发展,激发态的形成及其决定因素在几类经典的配合物中得以很好的研究,尤其是对d~3组态Cr(bpy)_3~(3+)和d~6电子组态Ru(bpy)_3~(2+)的研究尤为突出.二茂铁及其衍生物一直是有机金属化学研究的重要对象.其对Cr(bpy)_3~(3+),Ru(bpy)_3~(2+)等发光剂猝灭作用对分子器件的基础研究具有重要意义.为此,本文合成了一系列含茂铁基多核配合物,并研究了其对Cr(bpy)_3~(3+)发光过程的猝灭作用.  相似文献   

9.
在本文中,进一步发展了以二联吡啶二吡啶并[3,2-a:2',3'-c]吩嗪钌([Ru(bpy)_2dppz]~(2+))为电化学发光指示剂的DNA损伤传感器。将通过S-Au键组装在金电极表面的双链DNA浸泡在[Ru(bpy)_2dppz]~(2+)溶液中,利用[Ru(bpy)_2dppz]~(2+)是双链DNA分子"光开关"的特性,得到[Ru(bpy)_2dppz]~(2+)/DNA/Au电化学发光传感器,并优化了[Ru(bpy)_2dppz]~(2+)的浸泡时间,浸泡浓度等实验条件。发现在含有[Ru(bpy)_2dppz]~(2+)的底液中测定其电化学发光强度值比不含[Ru(bpy)_2dppz]~(2+)的底液中增强了6倍左右。此外将此传感器经全氟辛酸磺酸、五溴联苯醚、氧化苯乙烯等物质温浴后,其电化学发光强度显著降低,说明该传感器可用于环境污染物对DNA损伤的筛查测定。  相似文献   

10.
陈曦  贾丽  佐藤昌宪 《化学学报》1998,56(3):238-243
研究了碱性溶液中甲醇-联吡啶钌(II)[Ru(bpy)3^2^+]的电致化学发光行为。在玻碳电极上甲醇于+1.28V(vs.Ag/AgCl)处被氧化为甲氧基离子(CH3O.), 该自由基离子发生歧化反应, 生成激发态的甲醛(HCHO), 发出波长为545nm的光。另一方面当体系含有少量的Ru(bpy)3^2^+时会得到较强的发光信号, 发光波长为608nm, 该发光起因于在甲醇的氧化电位下, Ru(bpy)3^2^+被氧化成Ru(bpy)3^3^+, CH3O.与Ru(bpy)3^3^+反应, 生成激发态的Ru(bpy)3^2^+而发光。  相似文献   

11.
The Ru(bpy)_3~(2+) doped graphene oxide-silica composite film(Ru/GO-SiCF) was synthesized by one pot hydrolysis and condensation of tetraethylorthosilicate(TEOS) in the water-alcohol solution of graphene oxide and Ru(bpy)_3~(2+) at room temperature.The prepared Ru/GO-SiCF modified glassy carbon electrode(GCE) showed excellent electrochemiluminescence(ECL) behavior for the determination of tripropylamine(TPA) with high sensitivity and good stability.We expected this simple and novel material will find further application in construction of other targets sensors.  相似文献   

12.
Here,we developed a novel electrochemiluminescence resonance energy transfer(ECL-RET) approach between Ru(bpy)_3~(2+) and Au nanorods(NRs) for sensitive determination of H_2O_2.Au NRs were synthesized through silver ion-assisted seed-mediated method which exhibited an obvious absorption peak at about 627 nm.They were modified at glassy carbon electrode(GCE) surface which showed a significant ECL quenching efficiency about 56.5%due to the ECL-RET process.This Au NRs modified electrode was then utilized to measure the concentration of H_2O_2 on the basis of the significant quenching effect of H_2O_2 on Ru(bpy)_3~(2+) ECL.Results demonstrated that the decrement of ECL intensity at Au NRs modified electrode had ~ 6.6-fold enhancement as compared with that at bare electrode.  相似文献   

13.
Electrogenerated chemiluminescences (ECLs) based on tris(2,2′-bipyridine)ruthenium(II) (Ru(bpy)32+) and lupin alkaloids, for instance, sophoridine (SRI), matrine (MT), sophoranol (SR) and sophocarpine (SC) in an aqueous alkaline buffer solution (pH 9.0) are studied. The light emission is mainly caused by an electro-oxidation reaction between tertiary amino group on the alkaloid compounds and Ru(bpy)32+ in a thin layer flow cell equipped with a glassy carbon disc electrode (22.1 mm2) at the potential of +1.50 V (versus Ag/AgCl). The luminescence wavelength of 610 nm confirmed that ECL is caused by Ru(bpy)32+∗ to its ground state. ECL intensities of these lupin alkaloids are affected by the substituent character, three-dimensional conformation of hydrogen on β-carbon atom. Ionization potentials taken from calculation data further confirm the experimental results. In addition, the factors affecting the determination and HPLC separation of the four alkaloids are also investigated.  相似文献   

14.
报道了一种以钌(Ⅱ)-联吡啶[Ru(bpy)2+3]为催化剂的B-Z化学发光振荡新现象. 研究了B-Z化学发光振荡反应的影响因素, 并对体系的UV光吸收振荡进行了对比研究, 探讨了化学发光振荡反应的可能机理. 结果表明, 该体系的化学发光振荡是由于氧化态的钌(Ⅱ)-联吡啶被振荡反应过程中的强还原性中间体还原所引起的, 化学发光振荡随时间增加呈现周期性变化.  相似文献   

15.
赵丽  陶颖  陈曦 《化学学报》2006,64(4):320-324
通过电化学循环伏安法和电致化学发光方法,研究了Ru(bpy)32 在玻碳电极上的吸附,研究结果表明,2Ru(bpy)3 的浓度和与玻碳材料接触的时间,直接影响了Ru(bpy)32 在玻碳上的吸附.还考察了吸附的Ru(bpy)32 在玻碳电极上被氧化后脱附的情况.  相似文献   

16.
The electrochemiluminescence (ECL) of magnetic microbeads modified with tris(2,2'-bipyridine)ruthenium(II) ([Ru(bpy)3]2+) was studied in the presence of tri-n-propylamine (TPA) to develop highly sensitive ECL detection system, where the employed microbead has a diameter of 4.5 microm. The ECL signal of the [Ru(bpy)3]2+ derivative-modified magnetic microbeads was found to be affected by the geometrical distribution of the magnetic microbeads on the electrode surface. The ECL peak intensity increased with increasing the number of the beads on the electrode surfaces up to 1.6 x 10(6) beads cm(-2), although above 1.6 x 10(6) beads cm(-2), it decreased. The ECL decrease arises from the physical prevention of the ECL from reaching the photomultiplier tube by the excessive beads. The observed peak ECL signal of the [Ru(bpy)3]2+ derivative-modified magnetic microbeads in the presence of NaN3, which serves as a preservative substance, mainly appeared at a potential of +0.90 V vs Ag/AgCl where [Ru(bpy)3]2+ is hardly oxidized, whereas the ECL signal in the absence of NaN3 appeared at a potential of +1.15 V. The presence of NaN3 on the electrode surface retards formation of an oxide layer on the electrode surfaces and promotes TPA oxidation. The ECL response at +0.90 V was mainly attributed to ECL reaction of excited-state [Ru(bpy)3]2+* formed by oxidation of [Ru(bpy)3]+ with TPA radical cation, where the [Ru(bpy)3]+ was generated by reduction of [Ru(bpy)3]2+ with TPA radical.  相似文献   

17.
采用溶胶-凝胶法制备了含发光三吡啶钌[Ru(bpy)32+]分子的三官能度硅氧烷预聚液,并通过旋转涂敷及凝胶处理制备了高性能的薄膜,探讨了载体的微结构和发光分子的微环境效应。与传统的四官能度正硅酸乙酯(TEOS)/Ru(bpy)32+膜体系相比,含长链不饱和酯基的甲基丙烯酸丙酯基三甲氧基硅烷(PMA-TMS)/Ru(bpy)32+体系具有成膜性能好,气体的猝灭响应值高,响应时间短等特点。  相似文献   

18.
流动体系中维生素B~1的电致化学发光研究   总被引:7,自引:0,他引:7  
陈曦  陈薇  王小如 《化学学报》2000,58(5):563-566
在0.1mol/LNaOH水溶液中(pH12.6),维生素B~1的水解产物在玻碳电极上于+0.88V(vs.Ag/AgCl,下同)处被氧化,其氧化产物在+1.20V处与被氧化的Ru(bpy)~3^2^+反应,生成激发态的Ru(bpy)~3^2^+^*而发光,发光波长为609nm,研究结果表明水溶液的pH值影响了维生素B~1的水解速率,从而引起发光强度的明显差异。  相似文献   

19.
Bruce D  McCall J  Richter MM 《The Analyst》2002,127(1):125-128
The effects of electron withdrawing and electron donating groups on the electrochemiluminescent (ECL) properties of tris(2,2'-bipyridyl)ruthenium(II) (Ru(bpy)3(2+) where bpy = 2,2'-pyridine) are reported. The electrochemistry, photophysics and ECL of (bpy)2Ru(DC-bpy)2+, and (bpy)2Ru(DM-bpy)2+ (DC = 4,4'-dicarboxy-2,2'-bipyridine; DM = 4,4'-dimethyl-2,2'-bipyridine) have been studied relative to Ru(bpy)3(2+) in 50:50 (v/v) acetonitrile(CH3CN):H2O (0.1 M KH2PO4), and aqueous solutions. Furthermore, the effects of Triton X-100 (polyethylene glycol tert-octylphenyl ether) on the electrochemical, spectroscopic and ECL properties of these compounds are reported. The anodic oxidation of Ru(bpy)3(2+), (bpy)2Ru(DC-bpy)2+, and (bpy)2Ru(DM-bpy)2+ produces ECL in the presence of tri-n-propylamine (TPrA) in all solvent systems. ECL efficiencies (phi(ecl), photons produced per redox event) of 0.73 and 0.84 for (bpy)2Ru(DC-bpy)2+, and (bpy)2Ru(DM-bpy)2+ were obtained in aqueous buffered solution, using Ru(bpy)3(2+) as a relative standard (phi(ecl) = 1.0). Addition of 0.4 mM Triton X-100 results in a greater than 2-fold increase in ECL efficiences (i.e., 3.8, 2.4 and 2.3 for Ru(bpy)3(2+), (bpy)2Ru(DC-bpy)2+, and (bpy)2Ru(DM-bpy)2+, respectively) using aqueous Ru(bpy)3(2+) containing no surfactant as standard (phi(ecl) = 1.0). ECL efficiencies of 27.4, 16.5 and 26.1 were found in 50:50 (v/v) CH3CN:H2O (0.1 M KH2PO4) for Ru(bpy)3(2+), (bpy)2Ru(DC-bpy)2+, and (bpy)2Ru(DM-bpy)2+, respectively, using aqueous Ru(bpy)3(2+) containing no surfactant as standard (phi(ecl) = 1.0). Detailed studies support adsorption of surfactant on the electrode surface, thus facilitating TPrA and ruthenium oxidation.  相似文献   

20.
It was found that stannous chloride (SnCl(2)), as a popular inorganic reducing reagent, could obviously enhance the electrochemiluminescence (ECL) of tris(2,2'-bipyridyl) ruthenium(II) (Ru(bpy)(3)(2+)) in aqueous solution. Some factors affecting the ECL reactions between Ru(bpy)(3)(2+) and Sn(2+), including pH, concentrations of coreactant, and electrode materials, were investigated by comparison with a classic ECL coreactant tripropylamine (TPA). The Ru(bpy)(3)(2+)-Sn(2+) ECL coreactant system produces stronger and more stable ECL signals, can keep its excellent ECL activity over a wider pH range and has more choices in using electrode materials than the Ru(bpy)(3)(2+)-TPA ECL coreactant system. The ECL mechanism of the Ru(bpy)(3)(2+)-Sn(2+) coreactant system was also studied in detail.  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号