Disposable and low-cost pen-like sensor incorporating nucleic-acid amplification based lateral-flow assay for at-home tests of communicable pathogens

Abstract

Rapid at-home test is a good alternative to the gold standard quantitative polymerase chain reaction (qPCR) for early identification and management of infected individuals in pandemic. However, the currently available at-home rapid antigen kits and nucleic acid tests (NATs) are prone to false results. Although some CRISPR-mediated NATs enhanced accuracy, long turnaround time (ca. 1 h) and aerosol contamination due to additional open-lid reaction hinder its applicability for self-tests. Moreover, the accuracy of at-home NATs is also impacted by interference of sample matrix due to lack of sample purification. Here we report a Fast, Low-cost, Aerosol contamination-free and Sensitive molecular assay for at-Home tests of communicable pathogens (FLASH) incorporating oLAMP, a recently reported isothermal and target-specific NATs by our group, and a visible lateral-flow readout. The integrated platform enabled sample-to-result SARS-CoV-2 RNA detection in 20–30 min achieving a sensitivity of 0.5 copies/μL in a blinded experiment with a high accuracy comparable with the qPCR. Its prototype consists of two disposable pen-like instruments for single-step sample preparation and contamination-free NATs, respectively. The simplified workflow of the FLASH enabled detection to be readily conducted by untrained users for at-home tests. All in all, the FLASH prototype demonstrates itself to be a promising home-use assay platform for effective mitigation of the pandemic.

Keywords

• At-home test
• SARS-CoV-2
• Loop-mediated isothermal amplification
• One-pot loop probe-mediated isothermal amplification reaction
• Lateral-flow assay