The outbreak of COVID-19 has created a huge challenge to global health systems. Experience in fighting the epidemic shows that the development of a rapid and sensitive POCT diagnostic platform for SARS-CoV-2 that can be deployed in situ is crucial to contain the outbreak. Here, we have developed a portable microdroplet detection platform that integrated temperature controller and micro-stirring for high-throughput and ultrafast COVID-19 diagnosis. Such a device uses a p-n junction (PN junction) as the temperature controller to adjust the temperature in a single microdroplet independently and precisely, ensuring the amplification of reverse transcription loop-mediated isothermal amplification (RT-LAMP). Meanwhile, the platform incorporates an ultrasonic micro-stirring unit, greatly increasing the interaction between RT-LAMP molecules and accelerating the amplification. The results show good linearity over a wide linear range (1 to 10⁵ copies/μL) and low LOD (0.48 copy/μL). Our method reports in only 6.1 min for high-viral load samples, and combines with sample preparation, the total detection process could be done within 30 min. Such a portable and fully integrated microdroplet molecular diagnostic platform is a promising tool for point-of-care diagnosis of COVID-19 and other infectious diseases in resource-limited settings.

COVID-19 的爆发给全球卫生系统带来了巨大挑战。抗疫经验表明，开发可原位部署的快速灵敏的SARS-CoV-2 POCT诊断平台对遏制疫情至关重要。在这里，我们开发了一种便携式微滴检测平台，该平台集成了温度控制器和微搅拌，用于高通量和超快的 COVID-19 诊断。这种装置使用pn结（PN结）作为温度控制器，独立精确地调节单个微滴中的温度，确保逆转录环介导等温扩增（RT-LAMP）的放大。同时，该平台加入了超声波微搅拌单元，大大增加了RT-LAMP分子间的相互作用，加速了扩增。结果显示在很宽的线性范围内（1 至 10 ⁵拷贝/μL）和低 LOD（0.48 拷贝/μL）。我们的方法报告高病毒载量样本仅需 6.1 分钟，并结合样本制备，整个检测过程可在 30 分钟内完成。这种便携式且完全集成的微滴分子诊断平台是在资源有限的环境中对 COVID-19 和其他传染病进行即时诊断的很有前途的工具。