The gold standard for the diagnosis of SARS-CoV-2, the causative agent of COVID-19, is real-time polymerase chain reaction (PCR), which is labor-intensive, expensive, and not widely available in resource-poor settings. Therefore, it is imperative to develop novel, accurate, affordable, and easily accessible assays/sensors to diagnose and isolate COVID-19 cases. To address this unmet need, we utilized the catalytic potential of peroxidase-like DNAzyme and developed a simple visual detection assay for SARS-CoV-2 RNA using a conventional thermal cycler by the PCR-induced generation of DNAzyme sensor. The performance of RT-PCR DNAzyme-based sensor was comparable to that of real-time PCR. The pilot scale validation of RT-PCR DNAzyme-based sensor has shown ~100% sensitivity and specificity in clinical specimens (nasopharyngeal swab, n = 34), with a good correlation (Spearman r = 0.799) with the Ct-value of fluorescence probe-based real-time PCR. These findings clearly indicate the potential of this inexpensive, sensitive, and specific molecular diagnostic test to extend our testing capabilities for the detection of SARS-CoV-2 to curtail COVID-19 transmission.

诊断 SARS-CoV-2（COVID-19 的病原体）的黄金标准是实时聚合酶链反应 (PCR)，该方法是劳动密集型、昂贵的，并且在资源匮乏的环境中无法广泛使用。因此，必须开发新颖、准确、经济且易于使用的检测方法/传感器来诊断和隔离 COVID-19 病例。为了解决这一未满足的需求，我们利用类过氧化物酶 DNAzyme 的催化潜力，并使用传统的热循环仪通过 PCR 诱导生成 DNAzyme 传感器，开发了一种简单的 SARS-CoV-2 RNA 视觉检测方法。基于 RT-PCR DNAzyme 的传感器的性能与实时 PCR 相当。基于 RT-PCR DNAzyme 的传感器的中试规模验证在临床样本（鼻咽拭子、 n = 34），具有良好的相关性（Spearman r = 0.799）与基于荧光探针的实时 PCR 的 Ct 值。这些发现清楚地表明，这种廉价、灵敏且特异性的分子诊断测试有潜力扩展我们检测 SARS-CoV-2 的测试能力，从而减少 COVID-19 的传播。