基于金粒子修饰二硫化钼纳米复合材料的电化学发光免疫传感器的构建及其应用研究

生物标志物的快速、精准检测对控制和预防疾病或病毒的暴发具有重要意义。该研究将三维花状Au@(MoS2/GO/o-MWNTs)纳米复合物(AMGMs)作为一种理想的基底,利用“三明治”免疫夹心组装法构筑一种高灵敏的电化学发光免疫传感器,并用于前列腺特异性抗原(PSA)的高灵敏检测。AMGMs不仅具有良好的导电性和生物相容性,其三维花状的立体结构可提供更多活性位点并加载更多抗体,显著增加了传感器的响应信号。采用电化学交流阻抗法和循环伏安法对组装过程进行跟踪,证实了该传感器组装的可行性,并采用电化学发光法研究了传感器对底液中不同浓度PSA的响应。结果表明,该传感器实现了对肿瘤标志物PSA的灵敏检测,其线性范围为0.1 pg/mL~50 ng/mL,检出限(S/N=3)为0.1 pg/mL,对实际样品的加标回收率为98.2%~106%。该方法的准确度良好,可为临床PSA检测提供准确可靠的新方法。     

基于四苯乙烯自聚集膜增强电化学发光灵敏检测溶解氧

该文发展了一种基于四苯乙烯(TPE)在电极表面自聚集增强鲁米诺电化学发光信号的新技术,并实现了溶解氧的定量测定。将TPE分子修饰至金电极表面,在室温下形成多孔隙、无定形的聚集态自组装薄膜,有效增加了电极比表面积与孔隙的协同作用,高效捕获氧气分子O_2与超氧阴离子自由基O■,使鲁米诺的电化学发光信号得到显著增强。TPE修饰电极具有较高的稳定性与较好的重现性。利用氮气排除氧气,可改变鲁米诺电化学发光强度,进而测定溶液中溶解氧的含量。研究显示,通氮时间(1～6 min)与溶解氧浓度在1.63～0.190 mg/L范围内呈良好线性关系,相关系数(r~2)为0.990 9,溶解氧初始浓度的最低检出限为1.89 mg/L。方法操作简单、检测快速、信号变化灵敏,为溶解氧的灵敏检测提供了新方法。     

基于Ru(bpy)■-三乙胺体系的电致化学发光生物传感器检测葡萄糖

联吡啶钌(Ru(bpy)■)拥有优良的电致化学发光(ECL)性能,但其较好的水溶性使其固载面临巨大问题。该文制备了Pt纳米粒子与Ru(bpy)■的复合物(Pt NPs-Ru),将其修饰于电极并进一步固载葡萄糖氧化酶(GOx)制得传感器。基于H2O2对Ru(bpy)■-三乙胺体系ECL信号的猝灭作用,随着葡萄糖浓度的增加,其在GOx的催化下原位产生的H2O2量增多,导致ECL信号逐渐减弱,从而实现葡萄糖的检测。ECL强度与葡萄糖浓度的对数在1.0×10-8~5.0×10-5 mol/L范围内呈良好的线性关系,检出限低至5.2×10-9 mol/L。传感器具有好的稳定性和高的选择性。Pt NPs-Ru复合物为ECL传感器的构建提供了良好平台,为葡萄糖检测提供了新方法。     

An Electrochemiluminesence Chiral Sensor for Propranolol Enantiomers Based on Functionalized Graphite‐like Carbon Nitride Nanosheets

Graphite‐like carbon nitride nanosheets (g‐C₃N₄) have been attracted considerable attention for their applications in catalysis and electrochemiluminesence (ECL) sensor. In this paper, a facile solvothermal method was employed to prepare the functionalized nanocomposites with metal salts cadmium carbonate (CdCO₃) and g‐C₃N₄ hybrids (g‐C₃N₄‐CdCO₃). The prepared materials were characterized by scanning electron microscope (SEM), X‐ray energy dispersive spectroscopy (EDX) and Fourier transform infrared spectra (FTIR). The nanocomposites was used not only as a new type luminophore but also as a chiral selector in this simple and sensitive ECL chiral sensor system for the recognition and detection of propranolol (Pro) enantiomers via quenching effect. The obvious difference of ECL signal of S‐Pro and R‐Pro was obtained. Thus, the sensor had the ability to distinguish Pro enantiomers. The mechanism of recognition was discussed by the theoretical calculation of binding constant and the water contact angle experiments. The sensor for Pro enantiomers was developed at wide concentration range from 0.001 to 1 mmol?L^?1. The sensor with excellent sensitivity, stability and reproducibility provide a new strategy based on ECL for chiral recognition and the ECL chiral sensor.     

Single‐Atom Iron Boosts Electrochemiluminescence

The traditional luminol–H₂O₂ electrochemiluminescence (ECL) sensing platform suffers from self‐decomposition of H₂O₂ at room temperature, hampering its application for quantitative analysis. In this work, for the first time we employ iron single‐atom catalysts (Fe‐N‐C SACs) as an advanced co‐reactant accelerator to directly reduce the dissolved oxygen (O₂) to reactive oxygen species (ROS). Owing to the unique electronic structure and catalytic activity of Fe‐N‐C SACs, large amounts of ROS are efficiently produced, which then react with the luminol anion radical and significantly amplify the luminol ECL emission. Under the optimum conditions, a Fe‐N‐C SACs–luminol ECL sensor for antioxidant capacity measurement was developed with a good linear range from 0.8 μm to 1.0 mm of Trolox.     

Electroactive Metal–Organic Frameworks as Emitters for Self‐Enhanced Electrochemiluminescence in Aqueous Medium

Metal–organic frameworks (MOFs) have limited applications in electrochemistry owing to their poor conductivity. Now, an electroactive MOF (E‐MOF) is designed as a highly crystallized electrochemiluminescence (ECL) emitter in aqueous medium. The E‐MOF contains mixed ligands of hydroquinone and phenanthroline as oxidative and reductive couples, respectively. E‐MOFs demonstrate excellent performance with surface state model in both co‐reactant and annihilation ECL in aqueous medium. Compared with the individual components, E‐MOFs significantly improve the ECL emission due to the framework structure. The self‐enhanced ECL emission with high stability is realized by the accumulation of MOF cation radicals via pre‐reduction electrolysis. The self‐enhanced mechanism is theoretically identified by DFT. The mixed‐ligand E‐MOFs provide a proof of concept using molecular crystalline materials as new ECL emitters for fundamental mechanism studies.     

电化学发光免疫传感技术在生物药物分析中的研究进展

随着生物及药物分析领域的不断扩展,发展高灵敏度及高选择性的分析手段以解决复杂样品体系中低浓度待测物的分析测试问题是十分迫切的需求.电化学发光分析方法由于具有线性范围宽,灵敏度高及可控性强等优点,是处理低浓度样品的有效工具.这种方法与免疫传感技术相结合,有利于实现生物体液等复杂样品中极低含量生化物质与药物的高选择性、高灵敏度检测.本文综述了电化学发光免疫传感技术的发展状况,介绍了近年来在电化学发光免疫传感中出现的新型固相载体、电化学发光探针和共反应物、以及多组分免疫传感技术等,并对其在生物药物分析中的应用情况进行了总结.     

Revealing Crystallization‐Induced Blue‐Shift Emission of a Di‐Boron Complex by Enhanced Photoluminescence and Electrochemiluminescence

Elucidating the effects of crystallization‐induced blue‐shift emission of a newly synthesized di‐boron complex (DBC) by enhanced photoluminescence (PL) and electrochemiluminescence (ECL) in the annihilation pathway was realized for the first time. The 57 nm blue‐shift and great enhancement in the crystalline lattice relative to the DBC solution were attributed to the restriction of intramolecular rotation (RIR) and confirmed by PL imaging, X‐ray diffraction, as well as DFT calculations. It was discovered that ECL at crystalline film/solution interfaces can be further enhanced by means of both co‐reactant route and RIR. The RIR contributions with co‐reactant increased ECL up to 5 times more. Very interestingly, the co‐reactant system was found to give off a red‐shifted light emission. Mechanistic studies reveal that a difference between location of the ECL in the co‐reactant route and that in the annihilation pathway leads to an alternative emission wavelength.     

Electrogenerated Chemiluminescence of Donor–Acceptor Molecules with Thermally Activated Delayed Fluorescence

The electrochemistry and electrogenerated chemiluminescence (ECL) of four kinds of electron donor–acceptor molecules exhibiting thermally activated delayed fluorescence (TADF) is presented. TADF molecules can harvest light energy from the lowest triplet state by spin up‐conversion to the lowest singlet state because of small energy gap between these states. Intense green to red ECL is emitted from the TADF molecules by applying a square‐wave voltage. Remarkably, it is shown that the efficiency of ECL from one of the TADF molecule could reach about 50 %, which is comparable to its photoluminescence quantum yield.     

Image‐Contrast Technology Based on the Electrochemiluminescence of Porous Silicon and Its Application in Fingerprint Visualization

The electrochemiluminescence (ECL) of porous silicon (pSi) has attracted great interest for its potential application in display technology and chemical sensors. In this study, we found that pSi with a different surface chemistry displayed an apparently different dynamic ECL process. An image‐contrast technology was established on the basis of the intrinsic mechanism of the ECL dynamic process. As a proof of principle, the visualization of latent fingerprints (LFPs) and in situ detection of TNT in fingerprints was demonstrated by using the ECL‐based image‐contrast technology.