A solid-state electrochemiluminescence biosensing switch for detection of DNA hybridization based on ferrocene-labeled molecular beacon

A solid-state electrochemiluminescence (ECL) biosensing switch incorporating quenching of ECL of ruthenium(II) tris-(bipyridine) (Ru(bpy)₃²⁺) by ferrocene (Fc) has been successfully developed for DNA hybridization detection. The important issue for this biosensing system is based on the ferrocene-labeled molecular beacon (Fc-MB), i.e. using the special Fc-MB to react with the target DNA and then change its structure, resulting in an ECL intensity change. Under the optimal conditions, the difference of ECL intensity before and after the hybridization reaction (ΔI_ECL) was linearly related to the concentration of the complementary sequence in the range of 10 fM-10 pM and the detection limit was down to 1.0 fM.     

电化学发光传感器在农业传感领域中的研究进展

基于电化学发光(ECL)分析法构建的电化学发光传感器具有灵敏度高、背景信号低、操作简单的优点,因此,它在农业、工业、环境、临床和食品等领域具有广泛的应用前景。 本文主要综述了电化学发光传感器检测农药残留和真菌毒素的应用及其相应的检测性能,分析了电化学发光传感器在农业传感领域的研究现状,并阐述了未来电化学发光传感器的发展趋势。     

利用聚丙烯酸钠-Nafion混合膜增强三联吡啶钌掺杂SiO_2纳米粒的电化学发光信号及其生物标记

对于三联吡啶钌(Ru(bpy)_3~(2+))掺杂的SiO_2纳米粒,以聚电解质聚丙烯酸钠和成膜物质Nafion的混合液对纳米粒进行包覆,制备了聚丙烯酸钠和Nafion混合膜包覆的电化学发光(ECL)纳米粒。结果表明:混合膜包覆的纳米粒,相对于Nafion膜的ECL信号增强了13倍。同时,混合膜表面可交换阳离子显著增加,能够通过离子交换固载大量的Ru(bpy)_3~(2+),纳米粒的ECL信号可进一步增强约3倍。混合膜还具有另外一个显著的优势,即通过混合膜的疏水相互作用可以方便地标记生物大分子,标记抗体仍然具有良好的免疫活性。     

3D石墨烯/SiO2@Ru(bpy)2+3修饰电极电化学发光测定敌草隆的研究

利用敌草隆对三联吡啶钌电化学发光(ECL)的增敏作用,以3D石墨烯和二氧化硅固定三联吡啶钌纳米复合材料(SiO2@Ru(bpy)32+)修饰的玻碳电极为工作电极,建立了一种直接快速检测敌草隆的电化学发光新方法.通过一步水热法合成了3D石墨烯以促进电子传递,油包水微乳液法合成SiO2@Ru(bpy)32+以提高发光效率.在最佳实验条件下,敌草隆浓度的对数在9.08×10-11～9.08×10-7 mol/L范围内与其相对发光强度呈良好的线性关系(r2 =0.998 9),检出限(S/N=3)为1.18×10-12 mol/L.连续测定2.00×l0-8 mol/L敌草隆10次,发光强度值的相对标准偏差(RSD)为4.2％,表明该方法具有良好的重复性.用该方法对青菜进行检测,回收率为99.3％～ 110.8％,结果满意.     

Diffusion and Reactivity of Ruthenium (II) Tris(bipyridine) and Cobalt (II) Tris(bipyridine) in Organically Modified Silicates

The diffusivity and reactivity of Ru(bpy)²⁺ ₃ and Co(bpy)²⁺ ₃ trapped within organically modified silicate (ORMOSIL) monoliths have been studied using electrogenerated chemiluminescence, voltammetry, and amperometry. For gel-encapsulated Ru(bpy)²⁺ ₃-tripropylamine, the shape and intensity of the luminescence-voltage curve was highly dependent on the amount of organoalkoxysilane introduced into the matrix. Likewise, for gel-encapsulated Co(bpy)²⁺ ₃, the magnitude of the diffusion coefficient and its rate of change with drying was also dependent on the organic modifier in the gel. A comparison of the results to those obtained with the gels prepared solely from tetramethoxysilane revealed enhanced diffusivity and reactivity of the reagents encapsulated in the ORMOSIL matrix.     

中性体系中鲁米诺电化学发光行为

研究了中性体系中鲁米诺的电化学发光行为。通过对Pt电极的预处理 ,以Br-为增强剂 ,在硼酸中性缓冲溶液中 ,0 .75V(vs .Ag)的正矩形脉冲激励下 ,得到鲁米诺良好的电化学发光信号。其强度在 2 .0× 10 -8～ 3.6× 10 -5mol/L之间与浓度存在定量关系 ;检出限可达 8.0× 10 -9mol/L。     

基于胶束反向扫集的毛细管电泳量子点电化学发光研究

研究了胺分子对CdSe量子点电化学发光的增强作用，构建了CdSe量子点电化学发光传感器.结合胶束扫集预富集技术，发展了一种基于胶束反向扫集的毛细管电泳（CE）量子点（QD）电化学发光（ECL）新方法用于莱克多巴胺和克伦特罗的同时分离检测.毛细管内首先充满含有十二烷基硫酸钠（SDS）胶束的缓冲溶液，电动进样时，样品分子进入毛细管，在入口端被迎面而来的SDS胶束捕获并富集，经CE分离后顺次进入检测端，根据不同浓度的胺分子对CdSe量子点发光强度的增强作用不同，实现对不同胺分子的同时分离检测.胶束反向扫集富集技术，使胶束-样品结合物在毛细管中处于准静止状态，进样时间可达50 min，量子点电化学发光信号增强6000倍.该方法成功用于猪肉样品中莱克多巴胺和克伦特罗的同时分离检测，其线性范围分别为（0.8~2960）和（3.0~5520）μg/L，检出限分别为96.8和192.5 ng/L.     

玻碳电极上Ru(bpy)32+的吸附及其电致化学发光的研究

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, Ru(bpy)₃²⁺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 在玻碳电极上被氧化后脱附的情况.     

Formation of [Ru(bpy)3]2+‐Containing Microstructures Induced by Electrostatic Assembly and Their Application in Solid‐State Detection of Electrochemiluminescence

Tris(2,2′‐bipyridine)ruthenium(II) ([Ru(bpy)₃]²⁺) is one of the most extensively studied and used electrochemiluminescent (ECL) compounds owing to its superior properties, which include high sensitivity and stability under moderate conditions in aqueous solution. In this paper we present a simple method for the preparation of [Ru(bpy)₃]²⁺‐containing microstructures based on electrostatic assembly. The formation of such microstructures occurs in a single process by direct mixing of aqueous solutions of [Ru(bpy)₃]Cl₂ and K₃[Fe(CN)₆] at room temperature. The electrostatic interactions between [Ru(bpy)₃]²⁺ cations and [Fe(CN)₆]^3? anions cause them to assemble into the resulting microstructures. Both the molar ratio and concentration of reactants were found to have strong influences on the formation of these microstructures. Most importantly, the resulting [Ru(bpy)₃]²⁺‐containing microstructures exhibit excellent ECL behavior and, therefore, hold great promise for solid‐state ECL detection in capillary electrophoresis (CE) or CE microchips.