State Research Institute Center for Physical and Technological Sciences, Sauletekio ave. 3, Vilnius, Lithuania; Department of Physical Chemistry, Faculty of Chemistry and Geosciences, Vilnius University, Naugarduko str. 24, 03225 Vilnius, Lithuania.
Department of Physical Chemistry, Faculty of Chemistry and Geosciences, Vilnius University, Naugarduko str. 24, 03225 Vilnius, Lithuania.
Sci Total Environ. 2024 Jan 15;908:168154. doi: 10.1016/j.scitotenv.2023.168154. Epub 2023 Nov 1.
In this study, we are reporting an electrochemical biosensor for the determination of three different clones of monoclonal antibodies (mAbs) against the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) recombinant nucleocapsid protein (rN). The nucleocapsid protein was chosen as a system component identifying and discriminating antibodies that occur after virus infection instead of S protein used in serological tests to measure antibodies raised after vaccination and infection. The sensing platform was based on a screen-printed carbon electrode (SPCE) covered with gold nanoparticles (AuNP) and subsequently modified with a self-assembled monolayer (SAM) to ensure the covalent immobilization of the rN. The interaction between the protein and three clones of mAbs against SARS-CoV-2 rN with clone numbers 4G6, 7F10, and 1A6, were electrochemically registered in the range of concentrations. Three techniques, cyclic voltammetry (CV), differential pulse voltammetry (DPV), and pulse amperometric detection (PAD) were used for the detection. A gradual change in the responses with an increase in mAbs concentration for all techniques was observed. To assess the performance of the developed electrochemical biosensor, 'complexation constant' (K), limit of detection (LOD), and limit of quantification (LOQ) were calculated for all assessed clones of mAbs and all used techniques. Our results indicated that DPV possessing higher fitting accuracy illustrated more significant differences in K constants and LOD/LOQ values. According to the DPV results, 7F10 clone was characterized with the highest K value of 1.47 ± 0.07 μg/mL while the lowest LOD and LOQ values belonged to the 4G6 clone and equaled 0.08 ± 0.01 and 0.25 ± 0.01 μg/mL, respectively. Overall, these results demonstrate the potential of electrochemical techniques for the detection and distinguishing of different clones of mAbs against SARS-CoV-2 nucleocapsid protein.
在这项研究中，我们报告了一种用于测定针对严重急性呼吸综合征冠状病毒 2（SARS-CoV-2）重组核衣壳蛋白（rN）的三种不同单克隆抗体（mAb）克隆的电化学生物传感器。选择核衣壳蛋白作为系统成分，以识别和区分病毒感染后出现的抗体，而不是血清学测试中用于测量疫苗接种和感染后产生的抗体的 S 蛋白。传感平台基于带有金纳米粒子（AuNP）的丝网印刷碳电极（SPCE），并用自组装单层（SAM）进行修饰，以确保 rN 的共价固定化。该蛋白质与针对 SARS-CoV-2 rN 的三种克隆 mAb（克隆号 4G6、7F10 和 1A6）之间的相互作用在浓度范围内通过电化学方式进行了记录。使用三种技术，循环伏安法（CV）、差分脉冲伏安法（DPV）和脉冲安培检测（PAD）进行检测。对于所有技术，都观察到随着 mAb 浓度的增加，响应逐渐变化。为了评估所开发的电化学生物传感器的性能，针对所有评估的 mAb 克隆和所有使用的技术，计算了“络合常数”（K）、检测限（LOD）和定量限（LOQ）。我们的结果表明，DPV 具有更高的拟合精度，表明 K 常数和 LOD/LOQ 值的差异更为显著。根据 DPV 的结果，7F10 克隆的 K 值最高，为 1.47±0.07μg/mL，而 LOD 和 LOQ 值最低的是 4G6 克隆，分别为 0.08±0.01μg/mL 和 0.25±0.01μg/mL。总体而言，这些结果表明电化学技术在检测和区分针对 SARS-CoV-2 核衣壳蛋白的不同 mAb 克隆方面具有潜力。
