The COronaVIrus Disease (COVID-19) is a newly emerging viral disease caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Rapid increase in the number of COVID-19 cases worldwide led the WHO declare pandemic within a few month after the first case of infection. Due to the lack of a prophylactic measure to control the virus infection and spread, early diagnosis and quarantining of infected as well as the asymptomatic individuals are necessary for the containment of this pandemic. However, the current methods for SARS-CoV-2 diagnosis are expensive and time consuming although some promising and inexpensive technologies are coming out for emergency use. In this work, we report the synthesis of a cheap yet highly sensitive cobalt-functionalized TiO2 nanotubes (Co-TNTs)-based electrochemical biosensor and its efficacy for rapid detection of spike glycoprotein of SARS-CoV-2 by examining S-RBD protein as the reference material. A simple, low-cost, and one-step electrochemical anodization route was used to synthesize TNTs, followed by an incipient wetting method for cobalt functionalization of the TNTs platform, which is connected to a potentiostat for data collection. This sensor specifically detected the S-RBD protein of SARS-CoV-2 even at very low concentration (range of 14 nM to 1400 nM). Additionally, our sensor showed a linear response in the detection of viral protein with concentration range. In summary, our Co-TNT sensor is highly effective in detecting SARS-CoV-2 S-RBD protein in approximately 30 seconds, which can be explored for developing a point of care diagnostics for rapid detection of SARS-CoV-2 in nasal secretions and saliva samples.

中文翻译：

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基于功能化TiO2纳米管的电化学生物传感器用于SARS-CoV-2的快速检测

冠状病毒病（COVID-19）是由严重的急性呼吸系统综合症冠状病毒2（SARS-CoV-2）引起的一种新兴病毒病。世界范围内COVID-19病例数的迅速增加导致世界卫生组织在第一例感染病例后的几个月内宣布大流行。由于缺乏控制病毒感染和传播的预防措施，因此，为控制这种流行病，必须对感染者以及无症状个体进行早期诊断和隔离。然而，尽管出现了一些有前途且廉价的技术用于紧急情况，但当前用于SARS-CoV-2诊断的方法既昂贵又费时。在这项工作中 我们报告了一种廉价但高度灵敏的钴功能化TiO2纳米管（Co-TNTs）基电化学生物传感器的合成及其通过检查S-RBD蛋白作为参考材料而快速检测SARS-CoV-2穗状糖蛋白的功效。使用一种简单，低成本且一步一步的电化学阳极氧化路线来合成TNT，然后采用初期润湿方法对TNTs平台的钴进行功能化，然后将其连接到恒电位仪进行数据收集。即使在非常低的浓度（14 nM至1400 nM的范围）下，该传感器也能特异性检测SARS-CoV-2的S-RBD蛋白。此外，我们的传感器在检测浓度范围内的病毒蛋白时显示出线性响应。总而言之，我们的Co-TNT传感器可在大约30秒内高效检测SARS-CoV-2 S-RBD蛋白，