A fully-enclosed prototype 'pen' for rapid detection of SARS-CoV-2 based on RT-RPA with dipstick assay at point-of-care testing.

A fully-enclosed prototype 'pen' for rapid detection of SARS-CoV-2 based on reverse transcriptase isothermal recombinase polymerase amplification (RT-RPA) with dipstick assay was developed. The integrated handheld device, consisting of amplification, detection and sealing modules, was developed to perform rapid nucleic acid amplification and detection under a fully enclosed condition. After RT-RPA amplification with a metal bath or a normal PCR instrument, the amplicons were mixed with dilution buffer prior to being detected on a lateral flow strip. To avoid aerosol contamination causing false-positive, from amplification to final detection, the detection 'pen' had been enclosed to isolate from the environment. With colloidal gold strip-based detection, the detection results could be directly observed by eyes. By cooperating with other inexpensive and rapid methods for POC nucleic acid extraction, the developed 'pen' could detect COVID-19 or other infectious diseases in a convenient, simple and reliable way.