Key Laboratory of Optic-electric Sensing and Analytical Chemistry for Life Science, MOE, Shandong Key Laboratory of Biochemical Analysis, Key Laboratory of Analytical Chemistry for Life Science in Universities of Shandong, College of Chemistry and Molecular Engineering, Qingdao University of Science and Technology, Qingdao, 266042, China.
Mikrochim Acta. 2021 May 31;188(6):217. doi: 10.1007/s00604-021-04859-1.
A flexible free-standing electrochemical biosensor to detect carcinoembryonic antigen (CEA) is described based on a conducting polypyrrole (PPy) nanocomposite film electrode. The conducting PPy composite was constructed by the sandwiched structure formed by PPy doped with pentaerythritol ethoxylate (PEE) and 2-naphthalene sulfonate (2-NS-PPy) separately via electropolymerization. Gold nanoparticles (AuNPs) were fixed on the PPy composite film by electrodeposition and then connected to CEA aptamer through self-assembly to construct a free-standing electrochemical biosensor breaking away from additional soft substrates and current collector. This PPy composite film-based electrochemical biosensor exhibits satisfying sensing performance for CEA detection, with a linear range from 10 g/mL to 10 g/mL and a detection limit of 0.033 ng/mL, good specificity and long-term sensing stability (96.8% of the original signal after 15 days). The biosensor also presents acceptable reproducibility with 1.7% relative standard deviation. Moreover, this electrochemical biosensor owns the deformation stability that could bear various deformations (twisting, folding, and knotting) without affecting device's sensing performance. It can even maintain 99.4% of the original signal under 25% strain deformation. Due to the superior sensing performance, high stability (mechanical deformation and long-term storage), and flexibility, this free-standing electrochemical biosensor proves huge potential in application of flexible and wearable electronics.
一种基于导电聚吡咯（PPy）纳米复合材料电极的灵活的独立式电化学生物传感器，用于检测癌胚抗原（CEA）。该导电 PPy 复合材料通过电聚合分别掺杂五氧化二磷乙氧基化物（PEE）和 2-萘磺酸（2-NS-PPy）形成夹层结构构建而成。金纳米粒子（AuNPs）通过电沉积固定在 PPy 复合膜上，然后通过自组装与 CEA 适体连接，构建了一种无需额外软基底和集流器的独立式电化学生物传感器。这种基于 PPy 复合膜的电化学生物传感器在 CEA 检测方面表现出令人满意的传感性能，线性范围为 10 fg/mL 至 10 fg/mL，检测限为 0.033 ng/mL，具有良好的特异性和长期传感稳定性（15 天后原始信号的 96.8%）。该生物传感器还具有可接受的重现性，相对标准偏差为 1.7%。此外，该电化学生物传感器具有变形稳定性，能够承受各种变形（扭曲、折叠和打结）而不影响器件的传感性能。它甚至可以在 25%的应变变形下保持 99.4%的原始信号。由于其出色的传感性能、高稳定性（机械变形和长期储存）和灵活性，这种独立式电化学生物传感器在柔性和可穿戴电子应用中具有巨大的潜力。
