DiagnosDisk - a highly sensitive point-of-care test for detecting SARS-CoV-2antigen in saliva

DiagnosDisk - 用于检测唾液中 SARS-CoV-2 抗原的高度灵敏的现场检测

• 批准号: 10544702
• 负责人: James Lai
• 金额: $ 13.42万
• 依托单位: NATIONAL TAIWAN UNIVERSITY OF SCIENCE AND TECHNOLOGY
• 依托单位国家: 美国
• 财政年份: 2022
• 资助国家: 美国
• 起止时间: 2022-02-01 至 2024-05-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/10544702
• 关键词: 2019-nCoV; Acute; Address; Adopted; Antibodies; Antigens; Biological Assay; Blood Plasma Volume; COVID-19; COVID-19 detection; COVID-19 pandemic; COVID-19 patient; COVID-19 screening; Centers for Disease Control and Prevention (U.S.); Cessation of life; Contact Tracing; Coupling; Data; Deposition; Detection; Development; Devices; Diagnosis; Early Diagnosis; Enzyme-Linked Immunosorbent Assay; Equipment; Evaluation; Exhibits; Goals; Gold; Gold Colloid; Human Resources; Hydrophobicity; Image; Immunoassay; Individual; Infection; Lateral; Location; Malaria; Measures; Membrane; Noise; Nucleocapsid; Patients; Plasma; Polymers; Precipitation; Prostate-Specific Antigen; Proteins; Reagent; Reverse Transcriptase Polymerase Chain Reaction; SARS coronavirus; SARS-CoV-2 antigen; SARS-CoV-2 infection; SARS-CoV-2 negative; SARS-CoV-2 positive; Saliva; Salivary; Sampling; Scanning; Sensitivity and Specificity; Signal Transduction; Specimen; Temperature; Testing; Time; Training; United States; Viral Antigens; Viral Load result; Virus; Visual; acute infection; antibody conjugate; antigen binding; antigen detection; design; detection assay; detection limit; hydrophilicity; improved; innovation; medical attention; novel; pandemic disease; point of care testing; rapid test; saliva sample; salivary assay; sample collection; scale up; screening; success; viral RNA

Project Summary/Abstract SARS-CoV-2, a global pandemic, has caused more than 6 million infections and 180,000 deaths in the United States alone during the past 7 months. Both the WHO and CDC emphasize the need for point-of-care (POC) tests to expand diagnosis of acute infections to control the pandemic (i.e. isolating infected individuals). The current gold standard test for diagnosing acute SARS-CoV-2 infection is reverse transcriptase polymerase chain reaction (RT-PCR) with nasopharyngeal samples. The assay is highly sensitive, but requires well-trained personnel for sample collection and locations with specialized equipment. Therefore, the turnaround time varies from one to few days, delaying isolation, contact tracing, and medical attention. These challenges can be addressed with lateral flow immunoassays (LFIA) to detect viral antigens in self-collected saliva samples. Compared to nasopharyngeal specimens, studies have demonstrated that assays with saliva samples are more consistent and the saliva itself may contain higher viral load. However, existing LFIA for detecting salivary antigens exhibit poor sensitivity (≤ 40%) caused by the use of small sample volumes and sample dilution. To achieve timely and accurate screening of suspected COVID-19 cases, this project aims to develop a rapid assay for detecting SARS-CoV-2 antigens in saliva with high sensitivity to meet WHO's target product profile. We hypothesize that using ≥500 µL saliva as the assay sample can significantly improve the sensitivity because a larger specimen volume provides more analytes for detection. The new test will employ temperature-responsive polymer-antibody conjugates in conjunction with DiagnosDisk, a novel flow-through assay device. The approach is innovative in in using enriched saliva specimens for more consistent assay results, enhancing antigen detection by scaling up the saliva specimen volume, and adopting the well- developed sandwich immunoassay for DiagnosDisk with temperature-responsive polymer reagents that simplify the design while maximizing the sensitivity. We will employ polymer-antibody conjugates that efficiently isolate analytes in saliva (Aim 1) and fabricate the DiagnosDisk device to accommodate larger volume saliva specimens to improve the detection limit (Aim 2). The sensitivity of the new rapid assay, which combines polymer-antibody conjugates and DiagnosDisk, will be evaluated using saliva specimens from COVID-19 positive and negative patients (Aim 3).

项目摘要/摘要 SARS-COV-2是一项全球大流行，在统一造成了超过600万的感染和180,000人死亡 在过去的7个月中，单独的国家。 WHO和CDC都强调了需要掌握点的需求（POC） 测试以扩大急性感染的诊断以控制大流行（即隔离感染个体）。这 诊断急性SARS-COV-2感染的当前金标准测试是逆转录酶聚合酶 链咽样样品（RT-PCR）。该测定非常敏感，但需要训练有素 用于采样的人员和专用设备的位置。因此，周转时间 这些挑战可以从一到几天，延迟隔离，接触跟踪和医疗护理。 用侧向流免疫测定（LFIA）来检测自我收集的唾液样品中的病毒抗原。 与鼻咽标本相比，研究表明使用唾液样品的测定是 更一致，唾液本身可能包含较高的病毒载荷。但是，现有的LFIA检测 唾液抗原表现出敏感性不佳（≤40％），由小样品体积和样品引起 稀释。为了及时，准确地筛选可疑的Covid-19案件，该项目旨在发展 一种快速检测唾液中SARS-COV-2抗原具有高灵敏度以满足谁的目标产品的测定法 轮廓。我们假设使用≥500µL唾液作为测定样本可以显着提高灵敏度 因为较大的样品体积提供了更多用于检测的分析物。新测试将采用 温度响应性聚合物 - 抗体结合与Diagnosdisk结合在一起，这是一种新型流动性 测定设备。这种方法在使用富集的唾液标本以进行更一致的测定方面具有创新性 结果，通过扩大唾液标本体积来增强抗原检测并采用良好 开发了带有温度响应性聚合物试剂的诊断剂的三明治免疫测定法 简化设计，同时最大化灵敏度。我们将采用有效的聚合物抗体结合物 唾液中的分离分析物（AIM 1）并制造诊断设备以容纳更大的体积唾液 标本以提高检测极限（AIM 2）。新快速测定的敏感性，结合了 聚合物 - 抗体结合物和诊断剂将使用Covid-19的唾液标本进行评估 正患者和负面患者（AIM 3）。