School of Rehabilitation Medicine of Binzhou Medical University, Yantai, 264003, PR China.
School of Basic Medicine, Binzhou Medical University, Yantai, 264003, PR China.
Anal Biochem. 2022 Dec 1;658:114916. doi: 10.1016/j.ab.2022.114916. Epub 2022 Sep 18.
The detection of tumor markers in blood samples with high efficiency and sensitivity is in urgent need. In this work, a one-step quantitative detection assay for alpha fetal protein (AFP) based on gold microelectrode which is denoted as AuμE through square wave voltammetry using [Fe(CN)] as mediator was developed. As the biorecognition element of the assay, sulfydryl-modified AFP aptamer could be directly conjugated onto the surface of the AuμE, which could capture AFP with high specificity, and this attachment would cause the decrease of the capacitive current of the cyclic voltammetry due to the reduction of the active area of the electrodes. Under the optimized conditions, the AuμE aptasensor exhibited a linear detection range for AFP from 10 to 10 g/mL (S = 7.6 nA/dec, R = 0.991), and the detection limit is 2.5 × 10 g/mL. The AuμEs aptasensor demonstrates good selectivity against other types of proteins and small molecules, and has good reproducibility. The real blood samples were used for detection of AFP using the AuμEs aptasensor, the results agree well with those provided by the hospital through electrochemiluminescence method. Herein, the proposed one-step detection assay has a great application potential in point-of-care clinical diagnostics.
急需高效、灵敏地检测血液样本中的肿瘤标志物。在这项工作中，我们开发了一种基于金微电极的一步定量检测甲胎蛋白（AFP）的方法，该方法通过方波伏安法使用[Fe(CN)]作为介体进行检测。作为检测的生物识别元件，巯基修饰的 AFP 适体可以直接连接到 AuμE 的表面，它可以特异性地捕获 AFP，这种附着会由于电极活性面积的减少而导致循环伏安法的电容电流减少。在优化条件下，AuμE 适体传感器对 AFP 的线性检测范围为 10 到 10 g/mL（S=7.6 nA/dec，R=0.991），检测限为 2.5×10 g/mL。该 AuμE 适体传感器对其他类型的蛋白质和小分子具有良好的选择性和重现性。使用 AuμE 适体传感器对实际血液样本中的 AFP 进行检测，结果与医院通过电化学发光法提供的结果吻合良好。在此，所提出的一步检测方法在即时临床诊断方面具有很大的应用潜力。
