State Research Institute Center for Physical and Technological Sciences, Sauletekio Ave. 3, LT-10257 Vilnius, Lithuania.
NanoTechnas-Center of Nanotechnology and Materials Science, Faculty of Chemistry and Geosciences, Vilnius University, Naugarduko Str. 24, LT-03225 Vilnius, Lithuania.
Biosensors (Basel). 2022 Aug 3;12(8):593. doi: 10.3390/bios12080593.
In this research, we assessed the applicability of electrochemical sensing techniques for detecting specific antibodies against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) spike proteins in the blood serum of patient samples following coronavirus disease 2019 (COVID-19). Herein, screen-printed carbon electrodes (SPCE) with electrodeposited gold nanostructures (AuNS) were modified with L-Cysteine for further covalent immobilization of recombinant SARS-CoV-2 spike proteins (rSpike). The affinity interactions of the rSpike protein with specific antibodies against this protein (anti-rSpike) were assessed using cyclic voltammetry (CV) and differential pulse voltammetry (DPV) methods. It was revealed that the SPCE electroactive surface area increased from 1.49 ± 0.02 cm to 1.82 ± 0.01 cm when AuNS were electrodeposited, and the value of the heterogeneous electron transfer rate constant () changed from 6.30 × 10 to 14.56 × 10. The performance of the developed electrochemical immunosensor was evaluated by calculating the limit of detection and limit of quantification, giving values of 0.27 nM and 0.81 nM for CV and 0.14 nM and 0.42 nM for DPV. Furthermore, a specificity test was performed with a solution of antibodies against bovine serum albumin as the control aliquot, which was used to assess nonspecific binding, and this evaluation revealed that the developed rSpike-based sensor exhibits low nonspecific binding towards anti-rSpike antibodies.
在这项研究中，我们评估了电化学传感技术在检测新冠肺炎患者血清中针对严重急性呼吸综合征冠状病毒 2 (SARS-CoV-2) 刺突蛋白的特异性抗体的适用性。在此，通过电化学沉积法在丝网印刷碳电极（SPCE）上修饰具有金纳米结构（AuNS）的 L-半胱氨酸，进一步共价固定重组 SARS-CoV-2 刺突蛋白（rSpike）。使用循环伏安法（CV）和差分脉冲伏安法（DPV）评估 rSpike 蛋白与针对该蛋白的特异性抗体（抗-rSpike）的亲和相互作用。结果表明，当 AuNS 电沉积时，SPCE 的电活性表面积从 1.49 ± 0.02 cm 增加到 1.82 ± 0.01 cm，而异质电子转移速率常数（k）从 6.30 × 10 增加到 14.56 × 10。通过计算检测限和定量限来评估所开发的电化学免疫传感器的性能，得到 CV 的检测限和定量限分别为 0.27 nM 和 0.81 nM，DPV 的检测限和定量限分别为 0.14 nM 和 0.42 nM。此外，还使用牛血清白蛋白抗体溶液作为对照等分试样进行了特异性测试，以评估非特异性结合，评估结果表明，所开发的基于 rSpike 的传感器对抗-rSpike 抗体表现出低的非特异性结合。
