A scalable aptamer-based electrochemical biosensor for rapid detection of SARS-CoV-2 from saliva

摘要 COVID-19大流行是一个严重的全球公共卫生紧急情况，许多国家未能控制 病毒的传播是由于缓慢和不充分的测试。虽然现在有几种诊断方法，但大多数 测试是试剂密集型的，必须在CLIA批准的实验室中进行，这使得它们昂贵且缓慢， 报告结果，或快速和廉价，但可能缺乏灵敏度。在美国，严重的疾病和高- 高风险患者被优先进行检测，导致各州错过了轻度和无症状病例， 它们是病毒最有效的传播者然而，扩大测试一直是一个挑战， 最主要的是采样拭子和核酸扩增检测关键试剂短缺 很受欢迎的选择测试能力必须以指数方式扩展，以便能够对 所有患者、医护人员及其家属、其他关键工作人员以及更广泛的社区， 来控制疫情mPOD建议通过一种新型生物传感器扩展测试能力 它将使用被称为适体的寡核苷酸分子与SARS-CoV-2病毒的独特位点结合。 适体对抗体具有类似的结合亲和力，但由于其较小的尺寸，它们更灵活，使得 它们特别适合于高特异性结合。为了完成测试，将唾液样本加载到 含有固定在金电极上的适体的测试条。将金电极测试条插入 mPOD DTCT是一种专有的电化学测试平台，通过 循环伏安法，触发阳性结果。结果通过移动的应用程序无线发送， 将加密数据存储到云端，并传输到公共卫生机构，以增强数据收集，跟踪， 和COVID-19的追踪。该应用程序还将包括一个后端数据库，以帮助企业，制造商， 学校和大型机构跟踪测试个人的结果，并制定具体的公共卫生对策。为了 为了进一步开发这项技术，并实现快速部署，以及时进行COVID-19干预，mPOD计划 至1）选择SARS-CoV-2特异性适体用于具有优化信噪比的电极测试条 2）证明低成本、小型化恒电位仪测试条的灵敏度和特异性 作为COVID-19 POC或OTC诊断，3）完成并测试全面的数据数字基础设施 通过mPOD移动的应用程序收集、跟踪和追踪COVID-19检测结果。这种非传统方法 将提供新的检测能力，有可能比标准RT-PCR检测更快地报告结果， 与现有的基于抗原的诊断相比具有更高的准确性和灵敏度。此外，一旦 系统的开发，可以开发具有定制适体的测试条，用于快速诊断其他 病原体，包括未来新出现的大流行病，通过常规POC和OTC检测。

Abstract The COVID-19 pandemic is a critical global public health emergency and many countries are failing to contain the virus's spread due to slow and insufficient testing. While several diagnostic methods are now available, most tests are either reagent-intensive and must be done in CLIA-approved labs, making them expensive and slow to report results, or rapid and inexpensive, but potentially lacking in sensitivity. In the U.S., seriously ill and high- risk patients have been prioritized for testing, causing states to miss mild and asymptomatic cases, some of which are the most effective spreaders of the virus. However, expanding testing has been a challenge due to shortages of sampling swabs and key reagents for nucleic acid amplification-based tests, which are the most popular option. Testing capabilities must be expanded exponentially to enable mass population-level testing of all patients, healthcare workers and their families, other critical key workers, and the wider community in order to bring the pandemic under control. mPOD proposes to expand testing capabilities through a novel biosensor that will use oligonucleotide molecules called aptamers to bind to unique sites on the SARS-CoV-2 virus. Aptamers have similar binding affinities to antibodies, but due to their smaller size, they are more agile, making them particularly suited for high-specificity binding. To complete the test, a saliva sample will be loaded onto a test strip containing aptamers immobilized onto gold electrodes. The gold-electrode test strip will be inserted into the mPOD DTCT, a proprietary electrochemical test platform where virus-bound aptamers will be detected via cyclic voltammetry, triggering a positive result. The result is sent wirelessly via a mobile app, which sends encrypted data on to the cloud for storage and to public health agencies for enhanced data collection, tracking, and tracing of COVID-19. The app will also include a backend database to help businesses, manufacturers, schools, and large institutions track tested individuals' results and tailor specific public health responses. In order to further develop this technology and enable rapid deployment for timely COVID-19 intervention, mPOD plans to 1) Select SARS-CoV-2-specific aptamers for use in electrode test strips with an optimized signal-to-noise ratio performance, 2) Demonstrate sensitivity and specificity of a low-cost, miniaturized potentiostat test strip for use as a COVID-19 POC or OTC diagnostic, 3) Complete and test a fully-fledged digital infrastructure for data collection, tracking, and tracing of COVID-19 test results via the mPOD mobile app. This non-traditional approach will provide new testing capabilities with the potential to report results faster than standard RT-PCR tests and with greater accuracy and sensitivity compared to existing antigen-based diagnostics. Furthermore, once the system is developed, test strips with customized aptamers can be developed for rapid diagnosis of other pathogens, including future emerging pandemics, via routine POC and OTC testing.