Key Laboratory of Interfacial Reaction & Sensing Analysis in Universities of Shandong, School of Chemistry and Chemical Engineering , University of Jinan , Jinan 250022 , P.R. China.
Centre for Energy, Materials and Telecommunications , Institut National de la Recherche Scientifique , 1650 Boulevard Lionel-Boulet , Varennes , Québec J3X 1S2 , Canada.
ACS Appl Mater Interfaces. 2019 Mar 6;11(9):8945-8953. doi: 10.1021/acsami.9b01779. Epub 2019 Feb 22.
Novel ultrasensitive sandwich-type electrochemical immunosensor was proposed for the quantitative detection of insulin, a representative biomarker for diabetes. To this end, molybdenum disulfide nanosheet-loaded gold nanoparticles (MoS/Au NPs) were used as substrates to modify bare glassy carbon electrodes. MoS/Au NPs not only present superior biocompatible and large specific surface area to enhance the loading capacity of primary antibody (Ab) but also present good electrical conductivity to accelerate electron transfer rate. Moreover, the amino-functionalized cuprous oxide decorated with titanium dioxide octahedral composites (CuO@TiO-NH) were prepared to load dendritic platinum-copper nanoparticles (PtCu NPs) to realize signal amplification strategy. The resultant nanocomposites (cuprous oxide decorated with titanium dioxide octahedral loaded dendritic platinum-copper nanoparticles) demonstrate uniform octahedral morphology and size, which effectively increases the catalytically active sites and specific surface area to load the secondary antibody (Ab), even increases conductivity. Most importantly, the resultant nanocomposites possess superior electrocatalytic activity for hydrogen peroxide (HO) reduction, which present the signal amplification strategy. Under the optimal conditions, the proposed immunosensor exhibited a linear relationship between logarithm of insulin antigen concentration and amperometric response within a broad range from 0.1 pg/mL to 100 ng/mL and a limit detection of 0.024 pg/mL. Meanwhile, the immunosensor was employed to detect insulin in human serum with satisfactory results. Furthermore, it also presents good reproducibility, selectivity, and stability, which exhibits broad application prospects in biometric analysis.
新型超灵敏三明治型电化学免疫传感器被提出用于定量检测胰岛素，这是糖尿病的代表性生物标志物。为此，采用负载二硫化钼纳米片的金纳米粒子（MoS/Au NPs）作为基底来修饰裸玻碳电极。MoS/Au NPs 不仅具有优异的生物相容性和大的比表面积，可增强一级抗体（Ab）的负载量，而且具有良好的导电性，可加速电子转移速率。此外，制备了氨基功能化的氧化铜负载八面体二氧化钛复合材料（CuO@TiO-NH）来负载树枝状铂铜纳米粒子（PtCu NPs），以实现信号放大策略。所得的纳米复合材料（负载树枝状铂铜纳米粒子的氧化铜八面体）具有均匀的八面体形态和尺寸，这有效地增加了催化活性位点和负载二级抗体（Ab）的比表面积，甚至增加了电导率。最重要的是，所得的纳米复合材料对过氧化氢（HO）还原具有优异的电催化活性，呈现出信号放大策略。在最佳条件下，所提出的免疫传感器在 0.1 pg/mL 至 100 ng/mL 的宽浓度范围内对胰岛素抗原浓度的对数与电流响应呈线性关系，检测限低至 0.024 pg/mL。同时，该免疫传感器被用于检测人血清中的胰岛素，结果令人满意。此外，它还表现出良好的重现性、选择性和稳定性，在生物计量分析中具有广阔的应用前景。
