Electrochemical Determination of Flap Endonuclease 1 Activity Amplified by CRISPR/Cas12a Trans‐Cleavage**

Abstract

AbstractFlap endonuclease 1 (FEN1) participates in the DNA replication and repair processes, which plays an important role in maintaining genome stability. Determination of FEN1 level is highly required for biochemical studies and clinical diagnosis. Herein, a novel electrochemical approach for the detection of FEN1 is developed based on clustered regularly interspaced short palindromic repeats (CRISPR) and CRISPR‐associated (Cas) proteins trans‐cleavage. The dumbbell structured DNA substrate, single‐stranded DNA labelled with electrochemical species and three‐dimensional tetrahedral DNA are designed and involved in the reactions. This method displays high sensitivity and good specificity, which can not only monitor FEN1 in various biological samples directly, but also help screen FEN1 inhibitors with potential use for anti‐cancer drug discovery.