The ongoing spread of pandemic coronavirus disease (COVID-19) is caused by Severe Acute Respiratory Syndrome coronavirus 2 (SARS-CoV-2). In the lack of specific drugs or vaccines for SARS-CoV-2, demands rapid diagnosis and management are crucial for controlling the outbreak in the community. Here we report the development of the first rapid-colorimetric assay capable of detecting SARS-CoV-2 in the human nasopharyngeal RNA sample in less than 30 minutes. We utilized a nanomaterial-based optical sensing platform to detect RNA-dependent RNA polymerase (RdRp) gene of SARS-CoV-2, where the formation of oligo probe-target hybrid led to salt-induced aggregation and changes in gold-colloid color from pink to blue in the visible range. Accordingly, we found a change in colloid color from pink to blue in assay containing nasopharyngeal RNA sample from the subject with clinically diagnosed COVID-19. The colloid retained pink color when the test includes samples from COVID-19 negative subjects or human papillomavirus (HPV) infected women. The results were validated using nasopharyngeal RNA samples from suspected COVID-19 subjects (n=136). Using RT-PCR as a gold standard, the assay was found to have 85.29% sensitivity and 94.12% specificity. The optimized method has a detection limit as little as 0.5 ng of SARS-CoV-2 RNA. Overall, the developed assay rapidly detects SARS-CoV-2 RNA in clinical samples in a cost-effective manner and would be useful in pandemic management by facilitating mass screening.

中文翻译：

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用于快速检测临床样品中SARS-CoV-2的基于RNA的检测方法的开发

严重的急性呼吸系统综合症冠状病毒2（SARS-CoV-2）引起大流行性冠状病毒疾病（COVID-19）的持续传播。在缺乏针对SARS-CoV-2的特定药物或疫苗的情况下，快速诊断和管理需求对于控制社区暴发至关重要。在这里，我们报告了第一个快速比色测定法的发展，该测定法能够在不到30分钟的时间内检测人鼻咽RNA样品中的SARS-CoV-2。我们利用基于纳米材料的光学传感平台来检测RNA依赖的RNA聚合酶（RdRp）SARS-CoV-2基因，其中寡核苷酸探针-目标杂种的形成导致盐诱导的聚集，并且金胶体颜色在可见范围内从粉红色变为蓝色。因此，在含有来自临床诊断为COVID-19的受试者的鼻咽RNA样品的测定中，我们发现胶体颜色从粉红色变为蓝色。当测试包括来自COVID-19阴性受试者或人类乳头瘤病毒（HPV）感染妇女的样品时，胶体保持粉红色。使用来自怀疑的COVID-19受试者的鼻相RNA样本（n = 136）验证了结果。使用RT-PCR作为金标准，发现该测定的灵敏度为85.29％，特异性为94.12％。优化方法的检测限仅为0.5 ng SARS-CoV-2 RNA。总体，