School of Chemistry and Chemical Engineering, Chongqing University of Technology , Chongqing 400054, People's Republic of China.
Anal Chem. 2015 Mar 3;87(5):3094-8. doi: 10.1021/acs.analchem.5b00041. Epub 2015 Feb 19.
The development of electronic sensors with minimized usage of reagents and washing steps in the sensing protocols will significantly facilitate the detection of biomolecules. In this work, by using a new pseudoknot design of the aptamer probes, the construction of an electronic sensor for reagentless and single-step detection of immunoglobulin E (IgE) in human serum is described. The pseudoknot aptamer probes are self-assembled on the disposable electrode surface. The association of IgE with the aptamer probes leads to conformational changes of the pseudoknot aptamer structures and brings the redox-tags in close proximity to the electrode, resulting in amplified current response for monitoring IgE. The effects of the pseudoknot structure and the immobilization concentration of the aptamer probes on the sensor performance are evaluated. Under optimal conditions, the detection limit for IgE is estimated to be 60 pM. The sensor is also selective and can be employed to detect IgE in human serum samples. The developed sensor can achieve reagentless, washing-free and low-cost (with the disposable electrode) electrochemical detection of proteins, making this device a convenient sensing platform for the monitoring of different biomarkers when coupled with the appropriate aptamer probes.
在传感方案中，电子传感器的发展可以最大限度地减少试剂和洗涤步骤的使用，这将极大地方便生物分子的检测。在这项工作中，通过使用适体探针的新假结设计，描述了一种无需试剂和单步检测人血清中免疫球蛋白 E（IgE）的电子传感器的构建。假结适体探针在一次性电极表面自组装。IgE 与适体探针的结合导致假结适体结构的构象变化，并使氧化还原标记物靠近电极，从而产生用于监测 IgE 的放大电流响应。评估了假结结构和适体探针的固定浓度对传感器性能的影响。在最佳条件下，IgE 的检测限估计为 60 pM。该传感器还具有选择性，可用于检测人血清样品中的 IgE。开发的传感器可以实现无试剂、免洗涤和低成本（使用一次性电极）的电化学检测蛋白质，当与适当的适体探针结合时，该设备成为监测不同生物标志物的便捷传感平台。
