BIOSENSORS & BIOELECTRONICS
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2025
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IF 10.5
Bingjie Zheng,Yuqing Qin,Yanyan Chai,Aizhen Guo,Yonggang Hu
A DNA preamplification-free method was developed for sensitive detection of Salmonella typhimurium ( S. typhimurium ) by combining Pyrococcus furiosus Argonaute ( Pf Ago), a programmable small DNA-guided endonuclease and label-free DNAzyme, a functional nucleic acid (FNA). The effects of 5′-phosphorylated/hydroxylated single-strand DNA (5′P/OH ssDNA), including chimeric ssDNA-RNA and ssDNA-RNA-DNA (DNAzyme) on Pf Ago-mediated cleavage activity, were systematically investigated. Two detection strategies were developed: (1) A 63 nt 5′P DNAzyme was used as a guide DNA (gDNA) to mediate Pf Ago cleavage of probe MB1, resulting in a fluorescence signal inversely proportional to S. typhimurium concentration. RNase H2 from S. typhimurium (STH2) cleaved the DNAzyme, thereby reducing the signal. The limit of detection (LOD) was 4.5 × 10 CFU mL −1 , with a linear range from 8.0 × 10 to 6.4 × 10 4 CFU mL −1 (2) A 64 nt 5′OH DNAzyme was cleaved by STH2 to generate a 50 nt 5′P ssDNA, triggering Pf Ago-mediated MB2 cleavage. The fluorescence signal positively correlated with the concentration of S. typhimurium , with the LOD reduced to 2.0 × 10 CFU mL −1 and a detection range from 3.2 × 10 to 8.0 × 10 4 CFU mL −1 . Compared with the previous LOD of 3.2 × 10 3 CFU mL −1 achieved using the same DNAzyme labeled with a fluorescence probe and quencher, but without Pf Ago, the sensitivity of these methods was significantly improved, with increases of 71- and 160-folds, respectively. This method offers advantages of simplicity, specificity, rapidity, and sensitivity, making it suitable for point-of-care testing and holding promising potential for environmental monitoring, food safety, and clinical diagnosis.
研究领域:
分子诊断
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微生物检测
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核酸工程
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生物传感器
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食品安全
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产品关联
DOI
PubMed
高影响因子
JOURNAL OF HAZARDOUS MATERIALS
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2026
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IF 10.6
Ruibo Zhao,Jingjing Bai,Qiang Zhang,Jiayi Wei,Fei Deng,Myunghee Kim,Xingjie Li,Shuli Man,Weipan Peng,Long Ma
Rapid detection of foodborne pathogens is critical for food safety. Conventional qPCR offers high sensitivity but relies on nucleic acid amplification, increasing operational complexity and false-positive risks. Here, we developed a biosensor platform named PAF-SERS ( P f Ago-mediated A mplification- F ree S urface- E nhanced R aman S cattering Biosensor) for detecting Salmonella typhimurium ( S. typhimurium ) without pre-amplification. In this platform, Pf Ago specifically cleaves target DNA guided by a single-stranded DNA guide, generating a linker sequence that enables quantitative detection through SERS signal conversion. The assay completes within 55 min, with a detection limit as low as 10 CFU/mL and a linear range of 10^ 1 to 10^ 7 CFU/mL, exhibiting high specificity and reproducibility. We further applied a support vector machine (SVM) algorithm to accurately classify low-concentration samples. The method was successfully validated in milk, eggs, chicken, and feces and blood from infected mice, demonstrating its potential for rapid, on-site detection without bulky instruments.
✓ 已验证
DOI
PubMed
高影响因子
SENSORS AND ACTUATORS B-CHEMICAL
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2024
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IF 8
Jiali Qiao,Jingyu Jia,Weipan Peng,Minghui Lu,Yaru Li,Shuli Man,Shengying Ye,Long Ma
Early detection and control of foodborne diseases are crucial for ensuring food safety and consumer health. Therefore, there is a need for faster and more sensitive detection methods. We developed a rapid, portable and visible lateral flow biosensor (LFB) for foodborne pathogenic bacteria detection powered by a Pyrococcus furiosus Argonaute nuclease ( Pf Ago), named as Pf Ago-LFB. LAMP (Loop-mediated isothermal amplification) was used to amplify the target nucleic acid . By using Pf Ago as the “lighting up” technology, we can overcome the limitations of false-positive results and lack of effective endpoint monitoring in LAMP, greatly enhancing its applicability. It turned out that Pf Ago-LFB was able to provide yes-or-no (positive or negative) results with a limit of detection (LOD) as low as 1 CFU/mL for S. typhimurium and the detection range was between 10 0 to 10 8 CFU/mL. It was able to secure a sample-to-answer test for contaminated food samples in less than 45 min and demonstrated satisfactory selectivity. In summary, we designed a Pf Ago-LFB that rendered a novel, rapid, accurate, easy-to-deploy, on-site and yes or no detection of S. typhimurium , which could be generalized for building a “one-for-all” biosensing platform.
研究领域:
食品安全
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生物技术
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分子生物学
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病原体检测
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）