PDF(Pubmed)
Abstract：
Rapid and reliable immunosensing is undoubtedly one of the priorities in the efficient management and combat against a pandemic, as society has experienced with the SARS-CoV-2 outbreak; simple and cost-effective sensing strategies are at the forefront of these efforts. In this regard, 2D-layered MXenes hold great potential for electrochemical biosensing due to their attractive physicochemical properties. Herein, we present a V2CTx MXene-based sensing layer as an integral part of a label-free immunosensor for sensitive and selective detection of the SARS-CoV-2 spike protein. The sensor was fabricated on a supporting screen-printed carbon electrode using Nafion as an immobilizing agent for MXene and glutaraldehyde, the latter enabling effective binding of protein A for further site-oriented immobilization of anti-SARS-CoV-2 antibodies. A thorough structural analysis of the sensor architecture was carried out, and several key parameters affecting the fabrication and analytical performance of the immunosensor were investigated and optimized. The immunosensor showed excellent electroanalytical performance in combination with an impedimetric approach and exhibited a low detection limit of only 45 fM SARS-CoV-2 spike protein. Its practical applicability was successfully demonstrated by measuring the spike protein in a spiked artificial nasopharyngeal fluid sample.
摘要：
快速可靠的免疫传感无疑是有效管理和抗击大流行的优先事项之一,正如社会所经历的SARS-CoV-2疫情；简单且具有成本效益的传感策略是这些努力的最前沿。在这方面,2D层状MXenes由于其诱人的物理化学性质而具有电化学生物传感的巨大潜力。在这里，我们提出了一种基于V2CTxMXene的传感层，作为无标记免疫传感器的组成部分，用于灵敏和选择性地检测SARS-CoV-2刺突蛋白。使用Nafion作为MXene和戊二醛的固定剂，在支撑丝网印刷碳电极上制造传感器，后者能够有效结合蛋白A，以进一步固定抗SARS-CoV-2抗体。对传感器架构进行了彻底的结构分析，并对影响免疫传感器制备和分析性能的几个关键参数进行了研究和优化。免疫传感器与阻抗分析法结合显示出优异的电分析性能，并显示出仅45fMSARS-CoV-2刺突蛋白的低检测极限。通过测量加标人工鼻咽液样品中的刺突蛋白，成功证明了其实用性。
