Direct detection of SARS-CoV-2 using CRISPR-Cas13a and a mobile phone-based device. Fozouni. et al.

We report the development of an amplification-free CRISPR-Cas13a assay for direct detection of SARS-CoV-2 from nasal swab RNA that can be read with a mobile phone microscope. The assay achieved ~100 copies/uL sensitivity in under 30 minutes of measurement time and accurately detected pre-extracted RNA from a set of positive clinical samples in under 5 minutes. We combined crRNAs targeting SARS-CoV-2 RNA to improve sensitivity and specificity, and directly quantified viral load using enzyme kinetics. Integrated with a reader device based on a mobile phone, this assay has the potential to enable rapid, low-cost, point-of-care screening for SARS-CoV-2.