CRISPR-Cas9 Triggered Two-Step Isothermal Amplification Method for E. coli O157:H7 Detection Based on a Metal–Organic Framework Platform

作者：Xuan Sun, Yu Wang, Lu Zhang, Sha Liu, Man Zhang, Jiang Wang, Baoan Ning, Yuan Peng, Jing He, Yonggang Hu, Zhixian Gao · 发表于：Analytical Chemistry · 年份：2020 · DOI：10.1021/acs.analchem.9b04162 · 被引用次数：165 · 研究领域：Biosensors and Analytical Detection、Advanced biosensing and bioanalysis techniques、Salmonella and Campylobacter epidemiology

Escherichia coli O157:H7 has been reported as an important pathogenic bacteria causing serious infection and economic loss. However, detection of Escherichia coli O157:H7 needs improvement, given its current complexity and sensitivity. Herein, we attempt to build a fluorescence sensing method to detect Escherichia coli O157:H7 with easy operation and high efficiency. The target virulence gene sequences are recognized and cleaved by the CRISPR-Cas9 system, and trigger strand displacement amplification and rolling circle amplification. After amplification reactions, massive products can hybridize with the probes, the fluorescence of which are quenched based on a metal–organic framework platform, leading to the fluorescence recovery at typical excitation/emission wavelengths of 480/518 nm. This method exhibits high sensitivity with the detection limit at 4.0 × 10 1 CFU mL –1 and a wide range from 1.3 × 10 2 CFU mL –1 to 6.5 × 10 4 CFU mL –1 . Meanwhile, this assay also shows significant specificity and applies to practical samples with high accuracy. Therefore, our method would have great potential application in bacterial detection, food safety monitoring, or clinical diagnostics.