FIGURE 2.

Diagnostic strategies for SARS‐CoV‐2 nucleic acid detection. (a) CRISPR/Cas‐based detection; in the presence of target RNA sequences (blue), Cas proteins become activated and cleave fluorophore‐RNA‐quencher reporter molecules, resulting in an increase in fluorescence. (b) RNA toehold sensors; in the presence of target RNA, toehold sensors unfold, allowing ribosomes to bind and synthesize enzymes encoded by a messenger RNA (mRNA) sequence located downstream from the loop region. Newly synthesized enzymes then convert substrate into colored product. (c) MNAzymes; multi‐part nucleic acid (MNA)‐based enzymes assemble in the presence of target RNA and subsequently cleave reporter molecules to generate signal