Previous studies have confirmed that cytokeratin 19 fragment antigen 21-1 (CYFRA 21-1) serves as a powerful biomarker in non-small cell lung cancer (NSCLC). Herein, we report for the first time a label-free electrochemical immunosensor for sensitive and selective detection of tumor marker CYFRA21-1. In this work, three-dimensional graphene @ gold nanoparticles ([email protected]) nanocomposite was modified on the glassy carbon electrode (GCE) surface to enhance the conductivity of immunosensor. The anti-CYFRA21-1 captured and fixed on the modified GCE through the cross-linking of chitosan (CS), glutaraldehyde (GA) and anti-CYFRA21-1. The differential pulse voltammetry (DPV) peak current change due to the specific interaction between anti-CYFRA21-1 and CYFRA21-1 on the modified electrode surface was utilized to detect CYFRA21-1. Under optimized conditions, the proposed electrochemical immunosensor was employed to detect CYFRA21-1 and exhibited a wide linear range of 0.25–800 ng mL⁻¹ and low detection limit of 100 pg mL⁻¹ (S/N = 3). Moreover, the recovery rates of serum samples were in the range from 95.2% to 108.7% and the developed immunosensor also shows a good correlation (less than 6.6%) with enzyme-linked immunosorbent assay (ELISA) in the detection of clinical serum samples. Therefore, it is expected that the proposed immunosensor based on a [email protected] has great potential in clinical medical diagnosis of CYFRA21-1.

先前的研究已经证实，细胞角蛋白19片段抗原21-1（CYFRA 21-1）在非小细胞肺癌（NSCLC）中可作为强大的生物标志物。在此，我们首次报告了一种无标记的电化学免疫传感器，用于敏感和选择性地检测肿瘤标志物CYFRA21-1。在这项工作中，在玻璃碳电极（GCE）表面修饰了三维石墨烯@金纳米颗粒（[受电子邮件保护]）纳米复合材料，以增强免疫传感器的电导率。抗CYFRA21-1通过壳聚糖（CS），戊二醛（GA）和抗CYFRA21-1的交联被捕获并固定在修饰的GCE上。由于修饰的电极表面上抗CYFRA21-1和CYFRA21-1之间的特定相互作用而导致的差分脉冲伏安法（DPV）峰值电流变化被用于检测CYFRA21-1。^-1和100 pg mL ^-1的低检测限（S / N = 3）。此外，血清样品的回收率在95.2％至108.7％之间，并且开发的免疫传感器与酶联免疫吸附测定（ELISA）在临床血清样品的检测中也显示出良好的相关性（小于6.6％）。因此，期望所提出的基于[电子邮件保护的]免疫传感器在CYFRA21-1的临床医学诊断中具有巨大的潜力。