In situ hand-in-hand DNA tile assembly and CRISPR/Cas12a-based ultrasensitive detection for leukemia diagnosis

Abstract

CRISPR/Cas technology has attracted increasing attention for use in accurate and sensitive nucleic acid detection, and has innovated the field of molecular diagnostics. Because it is programmability and shows high fidelity and effective signal amplification capabilities. Specifically, Cas12a has been evaluated through in-depth research because it triggers collateral trans-cleavage activity for the target. Here, we report a novel CRISPR/Cas12a fluorescent biosensor by in situ hand-in-hand DNA tile assembly for leukemia diagnosis, and it allows an active isothermal amplification for multi-channel collection of CRISPR/cas12a transducers for achieving three-stage signal amplification. When the target gene concentration was in a range from 1 fM to 50 nM, the fluorescence intensity exhibited an excellent linear relationship with the logarithm of the target gene concentration, and the detection limit reached 1 fM. Furthermore, good detection performance can still be maintained in actual sample analysis. The CRISPR/Cas biosensor for leukemia diagnosis is more advanced than the traditional CRISPR/Cas detection systems, which can be used in cancer gene analyses, kinship judgment, environmental monitoring, and so on.