Ultrasensitive DNA Detection by Cascade Enzymatic Signal Amplification Based on Afu Flap Endonuclease Coupled with Nicking Endonuclease

Hail CESA! Cascade enzymatic signal amplification (CESA) for DNA detection is achieved in three steps: invasive signal amplification by Afu endonuclease to generate amplified flaps, flap ligation by T4 ligase to form a nicking site, and nicking reaction by nicking endonuclease to produce amplified signals (see picture for last step). The sensitivity of CESA is as high as 1 fM DNA.