共反应试剂增强电致化学发光信号生物传感器

在电致化学发光（ECL）生物传感器的构建中,利用共反应试剂促进发光基团的发光效率是一种常见、方便且非常有效的方法. 然而,如何更好地利用共反应试剂使其更加有效地与发光基团作用是提高该类生物传感器灵敏度的重要因素. 本文结合作者课题组部分工作综述了三种共反应试剂放大ECL信号的构建：共反应试剂内置于检测底液;共反应试剂共存于电极表面;酶促生成共反应试剂,并提出了今后ECL信号放大构建的展望.     

鲁米诺在铂电极上阳极电致化学发光的机理研究

研究了碱性鲁米诺溶液在多晶铂电极上的阳极电致化学发光(ECL)行为,观察到电极的预极化处理和溶解氧跟发光峰强度和峰形有直接关系。结合XPS谱图和Pt,Pt|S~a~d~s修饰电极的循环伏安特性,给出了鲁米诺阳极ECL两个发光通道的可能反应机理:(1)鲁米诺阴离子在表面有新鲜Pt原子的电极上氧化生成鲁米诺自由基,然后迅速与溶液中的氧反应形成0.22V(vs.Ag)处的发光肩峰;(2)电极表面的铂氧化物能加速原子态氧的发生过程,并增大0.60V(vs.Ag)附近ECL主峰的发光强度。     

共晶诱导增强的电化学发光9,10-二苯基蒽-苝微晶构建高效尿酸传感器

采用表面活性剂辅助自组装方法, 制得非共平面分子9,10-二苯基蒽(DPA)与平面型分子苝(Pe)形成的具有共晶诱导增强效应的电化学发光(ECL)新材料. DPA的引入不仅可以有效降低Pe分子因π-π作用聚集 引起的聚集诱导猝灭(ACQ)效应, 导致Pe分子的ECL发射从二聚体或多聚体激发态(¹Pe^2*)转变为单体激 发态(¹Pe^*); 还发挥了供体分子的作用, 为受体分子Pe提供了有效的能量传递, 进一步增强了ECL响应. 将该共晶发光材料修饰到玻碳电极表面构建了新型ECL尿酸传感器, 其对尿酸检测的线性范围为0.01 μmol/L~ 5.0 mmol/L, 检出限为4.0 nmol/L, 具有良好的选择性和稳定性.     

金纳米球/氮掺杂石墨烯量子点固载Ru(bpy)3^2+电致化学发光法检测邻苯二酚

利用还原法制得金纳米球(Au NPs),与氮掺杂石墨烯量子点(NG QDs)杂化后,再以壳聚糖胶黏剂并通过静电作用使Ru(bpy)3^2+负载于其表面形成复合膜,制备了一种新型的固相电致化学发光(ECL)传感器。研究发现,与单一材料相比,Au NPs和NG QDs杂化复合材料作为载体显著提高了发光试剂Ru(bpy)3^2+的ECL信号。根据环境污染物邻苯二酚对该修饰电极ECL信号较强的阻抑作用,建立了测定领苯二酚的新体系。结果表明,Au NPs/NG QDs/Ru(bpy)3^2+修饰电极的ECL信号变化值与邻苯二酚的浓度负对数在5.0 nmol/L^10μmol/L之间呈良好的线性关系,检出限为3.0 nmol/L(r=0.9992)。对5.0μmol/L的邻苯二酚进行10次重复测定,相对标准偏差为4.6%,常见的共存物质不干扰测定,表明该方法的选择性较好。采用该修饰电极成功测定了河水中的邻苯二酚含量。     

Concentration-Intensity Relationships in Electrogenerated Chemiluminescence

Abstract

Analytical applications of electrochemiluminescence are described. The peak intensity of luminescence, generated by application of an alternating current to solutions of 9,10-diphenylanthracene, varies linearly with concentration over the range 0.2 – 10 mM.     

Ultrafast Condensation of Carbon Nitride on Electrodes with Exceptional Boosted Photocurrent and Electrochemiluminescence

Semiconducting polymeric carbon nitride (CN) has drawn wide attention ranging from photocatalysis to more recent biosensing owing to unique defect‐tolerated optoelectronic properties and being metal‐free, cheap, and highly stable. However, at the core of electrical–optical interconversion, the preparation of the CN photoelectrode is still challenging. Now, the growth of CN on electrodes is achieved simply by microwave‐assisted condensation in seconds. The ultrafast heating not only addressed the thermodynamic contradiction of precursor volatilization during polymerization but also led to strongly adhesive CN layer on electrodes with gradient carbon‐rich texture, greatly accelerating the electron–hole separation and mobility. Consequently, the CN photoelectrode exhibited a remarkable photocurrent and a record cathodic efficiency of electrochemiluminescence up to 7 times that of benchmark Ru(bpy)₃Cl₂ in aqueous solution.     

Switching the Photoluminescence and Electrochemiluminescence of Liposoluble Porphyrin in Aqueous Phase by Molecular Regulation

By a facile peripheral decoration of 5-(4-aminophenyl)-10,15,20-triphenylporphyrin (ATPP) with inherent aggregation-induced emission (AIE) active tetraphenylethene (TPE), a versatile AIEgenic porphyrin derivative (ATPP-TPE) was obtained, which greatly abolishes the detrimental π–π stacking and thus surmounts the notorious aggregation-caused quenching (ACQ) effect of ATPP in aqueous phase. The photoluminescence of ATPP-TPE is 4.5-fold stronger than ATPP at aggregation state. Moreover, an unequivocal aggregation induced electrochemiluminescence (AIECL) of ATPP-TPE was found to be seriously dependent on its aggregation property in aqueous solution with efficiency of 34 %, which is 6 times higher than pure ATPP. The versatility of this molecular structure modulation strategy along with the ACQ-to-AIE transformation in this work provides direction to guide for applying liposoluble porphyrins in aqueous phase by designs of synthetic porphyrin AIEgens.     

空间分辨测量解析三(2,2'-联吡啶)钌(Ⅱ)电化学发光机理的研究进展

电化学发光(ECL)是由电化学反应引发,通过一系列化学反应产生激发态发光体进而辐射发光的过程,其产生的方式主要有湮灭型电化学发光和共反应剂型电化学发光.ECL是一种表面限域的发光过程,其发光层的厚度主要由反应中间体在电极表面的分布决定.空间分辨测量能够直接测得激发态发光体、共反应剂自由基等中间体在电极表面附近的分布,进...     

基于多壁碳纳米管修饰电极的保泰松的电致化学发光检测

基于保泰松对联吡啶钌的电致化学发光信号有较强的增敏作用, 使用多壁碳纳米管修饰玻碳电极作为工作电极, 建立了一种保泰松的电致化学发光检测方法. 对测定条件进行了一系列优化, 结果表明, 当发光试剂联吡啶钌的浓度为1.0×10－5 mol/L时, 在0.05 mol/L pH 10.20 的Na2HPO4-NaOH介质中保泰松对联吡啶钌电化学发光信号的增敏效果最强. 在此条件下, 保泰松的线性范围为0.5～200 μmol/L, 检测限(S/N＝3)为0.2 μmol/L, 与使用未经修饰的裸玻碳电极相比, 检测限下降了约一个数量级. 该检测方法还被用于加标人血清样品中保泰松的测定, 回收率在85.3%～95.0%之间, 结果令人满意, 可望用于保泰松的药物临床分析与质量监控.     

Determination of Quercetin Using Tris(2,2''''-bipyridyl) ruthenium (Ⅲ) Electrochemiluminescence (ECL) in Flowing Streams

Ru(bpy)32 electrochemiluminescence (ECL) was applied to determine quercetin. It was found that ECL intensity of Ru(bpy)32 could be enhanced in the presence of quercetin in basic solution, and the enhanced light emission intensity was proportional to the concentration of quercetin over the range of 1×10-6 mol/L to 2×10-4 mol/L.