Figure 1

Scheme for adapting isothermal amplification to a glucometer.
The detection scheme includes three steps: i) isothermal LAMP amplification of the target viral RNA/DNA produces flower-like amplicons containing four kinds of single-stranded loops, positioned between the target loci F2-F1 (F-target), F2c-F1c (F-probe), B2-B1 (B-probe) and B2c-B1c (B-target), respectively; ii) one of the LAMP loops (e.g., F-target) initiates a one-step strand displacement (OSD) reaction to release the Inv-FPc reporter sequence from FP conjugated to magnetic beads; iii) after magnetic separation, the released invertase on Inv-FPc reporter produces glucose and is read via a glucometer. F3: forward outer primer, B3: reverse outer primer, FIP: forward inner primer, BIP: reverse inner primer.