Department of Electronic Engineering, Gachon University, Seongnam-si, Gyeonggi-do, 13120, South Korea.
Department of Electronic Engineering, Gachon University, Seongnam-si, Gyeonggi-do, 13120, South Korea; School of Medicine and Pharmacy, The University of Danang, Danang, 550000, Viet Nam.
Talanta. 2022 Jan 15;237:122907. doi: 10.1016/j.talanta.2021.122907. Epub 2021 Sep 27.
In this paper, we developed a new ultrasensitive capacitance sensor for detection of amyloid beta 1-40 (aβ40) protein (one of Alzheimer's disease core biomarkers) in human serum based on the high supramolecular recognition of the β-cyclodextrin/reduced graphene oxide (β-CD/RGO) nanohybrid toward the anti-aβ40 antibody molecule. The sensor was established by immobilizing specific anti-aβ40 antibody onto the β-CD/RGO nanohybrid functionalized on indium tin oxide micro-disk electrode (anti-aβ40/β-CD/RGO/ITO). Detection of aβ40 in the human serum (HS) using the sensor anti-aβ40/β-CD/RGO/ITO is carried out by capacitance measurement without a redox probe to prevent protein denaturation, serving as a convenient strategy for point-of-care diagnosis. In comparison with other studies, the sensor shows a very low limit of detection of 0.69 fg mL in HS, demonstrating its ability for the ultrasensitive detection of aβ40. Using this sensor, the dissociation constant K of the binding interaction between anti-aβ40 and aβ40 in HS is found to be 2.9 × 10 nM, indicating the high binding affinity of antibody-antigen and the suitability of the anti-aβ40/β-CD/RGO/ITO sensor for aβ40 protein detection. The good selectivity of the anti-aβ40/β-CD/RGO/ITO sensor in the presence of differential analytes was also performed in this paper.
在本文中，我们基于β-环糊精/还原氧化石墨烯（β-CD/RGO）纳米杂化物对抗 aβ40 抗体分子的高超分子识别能力，开发了一种新的超灵敏电容传感器，用于检测人血清中的淀粉样蛋白β 1-40（aβ40）蛋白（阿尔茨海默病的核心生物标志物之一）。该传感器通过将特异性抗 aβ40 抗体固定在功能化有β-CD/RGO 纳米杂化物的铟锡氧化物微盘电极（抗 aβ40/β-CD/RGO/ITO）上来建立。使用传感器抗 aβ40/β-CD/RGO/ITO 通过电容测量检测人血清（HS）中的 aβ40，而无需使用氧化还原探针来防止蛋白质变性，这是一种用于即时诊断的便捷策略。与其他研究相比，该传感器在 HS 中的检测限低至 0.69 fg mL，显示出其对 aβ40 的超灵敏检测能力。使用该传感器，发现抗 aβ40 与 HS 中 aβ40 之间结合相互作用的解离常数 K 为 2.9 × 10 nM，表明抗体-抗原的高结合亲和力以及抗 aβ40/β-CD/RGO/ITO 传感器用于 aβ40 蛋白检测的适用性。本文还对存在差异分析物时抗 aβ40/β-CD/RGO/ITO 传感器的良好选择性进行了研究。
