Abstract：
Sensitive detection and point-of-care test of bacterial pathogens is of great significance in safeguarding the public health worldwide. Inspired by the characteristics of horseradish peroxidase (HRP), we synthesized a hybrid nanoflower with peroxidase-like activity via a three-component self-assembled strategy. Interestingly, the prepared nanozyme not only could act as an alternative to HRP for colorimetric biosensing, but also function as a unique signal probe that could be recognized by a pregnancy test strip. By combining the bifunctional properties of hybrid nanoflower, isothermal amplification of LAMP, and the specific recognition and non-specific cleavage properties of CRISPR/Cas12a system, the dual-readout CRISPR/Cas12a biosensor was developed for sensitive and rapid detection of Salmonella enterica. Moreover, this platform in the detection of Salmonella enterica had limits of detection of 1 cfu/mL (colorimetric assay) in the linear range of 101-108 cfu/mL and 102 cfu/mL (lateral flow assay) in the linear range of 102-108 cfu/mL, respectively. Furthermore, the developed biosensor exhibited good recoveries in the spiked samples (lake water and milk) with varying concentrations of Salmonella enterica. This work provides new insights for the design of multifunctional nanozyme and the development of innovative dual-readout CRISPR/Cas system-based biosensing platform for the detection of pathogens.
摘要：
细菌病原体的灵敏检测和即时检测对维护全球公共卫生具有重要意义。受辣根过氧化物酶（HRP）特性的启发，我们通过三组分自组装策略合成了具有过氧化物酶样活性的杂合纳米花。有趣的是,制备的纳米酶不仅可以作为比色生物传感HRP的替代品，但也可以作为一个独特的信号探针，可以通过妊娠试纸识别。通过结合杂化纳米花的双功能特性,LAMP的等温扩增,以及CRISPR/Cas12a系统的特异性识别和非特异性裂解特性，开发了双读出CRISPR/Cas12a生物传感器，用于敏感和快速检测肠道沙门氏菌。此外，该平台在肠道沙门氏菌的检测中,线性范围为101-108cfu/mL(比色法)的检出限为1cfu/mL,线性范围为102-108cfu/mL(侧流法)的检出限为102-108cfu/mL,分别。此外，开发的生物传感器在不同浓度的肠道沙门氏菌加标样品（湖水和牛奶）中表现出良好的回收率。这项工作为多功能纳米酶的设计以及基于CRISPR/Cas系统的创新双读出生物传感平台的开发提供了新的见解。
