Liustrovaite Viktorija, Ratautaite Vilma, Ramanaviciene Almira, Ramanavicius Arunas
NanoTechnas - Center of Nanotechnology and Materials Science, Institute of Chemistry, Faculty of Chemistry and Geosciences, Vilnius University (VU), Naugarduko St. 24, LT-03225, Vilnius, Lithuania; Department of Physical Chemistry, Institute of Chemistry, Faculty of Chemistry and Geosciences, Vilnius University (VU), Naugarduko St. 24, LT-03225, Vilnius, Lithuania.
Department of Physical Chemistry, Institute of Chemistry, Faculty of Chemistry and Geosciences, Vilnius University (VU), Naugarduko St. 24, LT-03225, Vilnius, Lithuania; Department of Nanotechnology, State Research Institute Center for Physical and Technological Sciences (FTMC), Sauletekio Ave. 3, LT-10257, Vilnius, Lithuania.
Biosens Bioelectron. 2025 Mar 15;272:117092. doi: 10.1016/j.bios.2024.117092. Epub 2024 Dec 29.
Herein, we report the development and characterisation of an electrochemical biosensor with a polypyrrole (Ppy)-based molecularly imprinted polymer (MIP) for the serological detection of the recombinant nucleocapsid protein of SARS-CoV-2 (rN). The electrochemical biosensor utilises a Ppy-based MIP formed on a self-assembled monolayer (SAM) at the gold interface to enhance Ppy layer stability on the screen-printed electrode (SPE). Electrochemical impedance spectroscopy (EIS) and square wave voltammetry (SWV) were employed for the electrochemical characterisation of screen-printed gold electrodes (SPGEs) modified with MIP or non-imprinted polymer (NIP) layers. Removing the rN protein template from the MIP layer increased electron transfer and decreased impedance, indicating the specificity of molecular imprinting. The electrochemical biosensor with a Ppy-based MIP exhibited higher sensitivity than the NIP counterpart, demonstrating its potential for selective rN protein detection. The limit of detection 0.4 nM and 0.2 nM and the limit of quantification 1.3 nM and 0.66 nM values obtained through SWV and EIS, respectively, highlight the biosensor's ability to detect low target protein concentrations. The specificity test confirmed minimal nonspecific binding, reinforcing the reliability of the novel electrochemical sensor with a Ppy-based MIP.
在此，我们报告了一种基于聚吡咯（Ppy）的分子印迹聚合物（MIP）的电化学生物传感器的开发与表征，用于血清学检测严重急性呼吸综合征冠状病毒2（SARS-CoV-2）的重组核衣壳蛋白（rN）。该电化学生物传感器利用在金界面的自组装单分子层（SAM）上形成的基于Ppy的MIP，以增强丝网印刷电极（SPE）上Ppy层的稳定性。采用电化学阻抗谱（EIS）和方波伏安法（SWV）对用MIP或非印迹聚合物（NIP）层修饰的丝网印刷金电极（SPGE）进行电化学表征。从MIP层中去除rN蛋白模板增加了电子转移并降低了阻抗，表明了分子印迹的特异性。具有基于Ppy的MIP的电化学生物传感器比NIP对应物表现出更高的灵敏度，证明了其用于选择性检测rN蛋白的潜力。通过SWV和EIS分别获得的检测限为0.4 nM和0.2 nM，定量限为1.3 nM和0.66 nM，突出了该生物传感器检测低浓度目标蛋白的能力。特异性测试证实了最小的非特异性结合，增强了具有基于Ppy的MIP的新型电化学传感器的可靠性。
