Guerrero S, Martínez-García G, Serafín V, Agüí L, Yáñez-Sedeño P, Pingarrón J M
Department of Analytical Chemistry, Faculty of Chemistry, University Complutense of Madrid, 28040-Madrid, Spain.
Analyst. 2015 Nov 21;140(22):7527-33. doi: 10.1039/c5an01185j.
The first electrochemical immunosensor for the determination of peptide YY is reported in this paper. A novel electrochemical platform, prepared by the electrochemical grafting of the diazonium salt of 4-aminobenzoic acid onto a reduced graphene oxide-modified glassy carbon electrode, was used, on which the covalent immobilization of specific anti-PYY antibodies was accomplished. The HOOC-Phe-rGO/GCEs were characterized using cyclic voltammetry and electrochemical impedance spectroscopy. The different variables affecting the preparation of the modified electrodes and the performance of the immunosensor were optimized. Under the optimized conditions, a calibration plot for PYY showing a linear range extending between 10(-4) and 10(2) ng mL(-1) was found. This range is adequate for the determination of this protein in real samples, since the expected concentration in human serum is around 100 pg mL(-1). The limit of detection was 0.01 pg mL(-1) of PYY. The immunosensor exhibited good reproducibility of the PYY measurements, excellent storage stability and selectivity, as well as a shorter assay time than those of ELISA kits. The usefulness of the immunosensor for the analysis of real samples was demonstrated by analyzing human serum samples spiked with PYY at three concentration levels.
本文报道了首个用于测定肽YY的电化学免疫传感器。使用了一种新型电化学平台，该平台通过将4-氨基苯甲酸重氮盐电化学接枝到还原氧化石墨烯修饰的玻碳电极上制备而成，在该平台上实现了特异性抗肽YY抗体的共价固定。采用循环伏安法和电化学阻抗谱对羧基苯丙氨酸-还原氧化石墨烯/玻碳电极进行了表征。对影响修饰电极制备和免疫传感器性能的不同变量进行了优化。在优化条件下，发现肽YY的校准曲线线性范围在10(-4)至10(2) ng mL(-1)之间。该范围足以用于实际样品中该蛋白质的测定，因为人血清中的预期浓度约为100 pg mL(-1)。肽YY的检测限为0.01 pg mL(-1)。该免疫传感器在肽YY测量中表现出良好的重现性、出色的储存稳定性和选择性，并且检测时间比酶联免疫吸附测定试剂盒更短。通过分析添加了三个浓度水平肽YY的人血清样品，证明了该免疫传感器在实际样品分析中的实用性。
