FOOD CHEMISTRY
·
2018
·
IF 4.946
Chun Wang,Keyu Xing,Ganggang Zhang,Meifang Yuan,Shaolan Xu,Daofeng Liu,Wenyao Chen,Juan Peng,Song Hu,Wei-Hua Lai
Escherichia coli O157:H7 ( E. coli O157:H7) is a potential threat to human health; thus, a rapid and sensitive method for detecting it is necessary. We designed a single-stranded DNA that contained an appended block and anchoring block. The appended block acted as a scaffold to prepare fluorescent Ag nanoclusters (AgNCs). The anchoring block contained Poly A, which bound with the surface of gold nanoparticles to quench the fluorescence of AgNCs. An interesting ELISA approach for detecting E. coli O157:H7 was established via fluorescent quenching of DNA-stabilized AgNCs by using a sandwich complex. The changes in fluorescence intensity of AgNCs were used to quantitatively detect E. coli O157:H7. The sensitivity for detecting E. coli O157:H7 reached 1.905 × 10 3 CFU/mL with a good linear range. Compared with conventional ELISA, the sensitivity of this technique increased by 30-fold. Moreover, this method demonstrated specificity and reproducibility and could be used in food samples.
研究领域:
生物技术
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分析化学
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微生物学
·
食品科学
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产品关联
DOI
PubMed
高影响因子
Frontiers in Chemistry
·
2022
·
IF 5.545
Wang Huan,Fan Yanmiao,Yang Qiaoli,Sun Xiaoyu,Liu Hao,Chen Wei,Aziz Ayesha,Wang Shenqi
Redox activity is an important indicator for evaluating electrochemical biosensors. In this work, we have successfully polymerized indole-5-carboxylic acid into poly-5-carboxyindole nanomaterials (PI-5-CA), using its superior redox activity, and introduced carboxylated single-walled carbon nanotubes (C-SWCNTs) to synthesize a composite material. Finally, a synthesized composite material was used for the modification of the glass carbon electrode to fabricate the PI-5-CA/C-SWCNTs/GCE-based immunosensor and was successfully applied for the sensitive detection of E. coli O157:H7. The fabricated immunosensor exhibited an outstanding electrocatalytic activity toward the detection of E. coli O157:H7 with a remarkably lowest limit of detection (2.5 CFU/ml, LOD = 3 SD/k, n = 3) and has a wide linear range from 2.98×101 to 2.98×107 CFU/ml. Inspired from the excellent results, the fabricated electrode was applied for the detection of bacteria from real samples (water samples) with a good recovery rate (98.13–107.69%) as well as an excellent stability and specificity. Owing to its simple preparation, excellent performance, and detection time within 30 min, our proposed immunosensor will open a new horizon in different fields for the sensitive detection of bacteria from real samples.
研究领域:
生物传感
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材料科学
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微生物学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
ULTRASONICS SONOCHEMISTRY
·
2019
·
IF 7.279
Lin Lin,Xinlei Wang,Changzhu Li,Haiying Cui
Ultrasonic sterilization (US), as a promising non-thermal sterilization method, exhibits unique superiorities than traditional sterilization methods. In this study, the inactivation mechanism of E. coli O157:H7 under US was investigated in cucumber and bitter gourd vegetable juices. Results revealed that the US treatment showed good antibacterial ability in countering E. coli O157:H7. Through determinations of conductivity and β -galactosidase activity, significant augmentation in membrane permeability of the bacteria was confirmed after the US treatment. The morphologies of the US treated E. coli O157:H7 demonstrated that the integrity of the cell membrane was disrupted by US treatment. SDS-PAGE and LSCM data further proved the disruptive action of US, leading to the leakage of proteins and DNA through the breakage on cell membrane. The decrease of metabolic-related enzyme activity was verified through investigation of bacterial metabolism. The antibacterial mechanism analysis indicated that the US can generate free radicals which resulted in the rise of intracellular oxidative stress, attenuation of energy metabolism and inhibition of hexose monophosphate pathway. As the application verification, the US treatment can cause the deprivation of E. coli O157:H7 cell viability in vegetable juices without obvious impact on the sensory quality.
研究领域:
食品科学
·
微生物学
·
生物技术
✓ 已验证
产品关联
DOI
PubMed
高影响因子
RSC Advances
·
2022
·Vol. 12
·期 46
·30174-30180
·
IF 4.036
Danqing Liu,Xingxing Lv,Chaoyue Zhao,Jiayue Li,Jinmei Huang,Ling Weng,Liangcan He,Shaoqin Liu
Foodborne or water-borne pathogens pose great threats to human beings and animals. There is an urgent need to detect pathogens with cheap, rapid and sensitive point-of-care diagnostic assays. Herein, we report the electrochemiluminescent (ECL) behaviors of NaBiF4 : Yb3+/Er3+ upconversion nanoparticles (UCNPs) which were synthesized via a fast and environment-friendly method at room temperature for the first time. The UCNPs together with K2S2O8 exhibit high ECL intensity and stable cathodic signals. Further, the Au nanoparticles (Au NPs) and Anti-E. coli O157 : H7 antibody were assembled on the surface of UCNPs successively to construct a novel ECL immunosensor for the detection of deadly E. coli O157 : H7. The as-prepared ECL immunosensor reveals high sensitivity to E. coli O157 : H7 in a linear range of 200–100 000 CFU mL−1, and the minimum detection limit could reach up to 138 CFU mL−1. The designed UCNP-based biosensor demonstrates high specificity, good stability and remarkable repeatability, and the strategy will provide a sensitive and selective method for rapid detection of E. coli O157 : H7 in food safety and preclinical diagnosis.
研究领域:
生物传感技术
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食品安全检测
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微生物学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
SENSORS AND ACTUATORS B-CHEMICAL
·
2021
·
IF 7.46
Ting Zheng,Xiaoming Jiang,Naiwen Li,Xia Jiang,Chao Liu,Jing-Juan Xu,Peng Wu
Escherichia coli O157:H7 ( E. coli O157:H7 ) is typically associated with food- and water-borne outbreaks, thus making continuous monitoring essential. Photoelectrochemical (PEC) detection, which harvests the unique photo-to-electric property of photoactive species, has emerged as an exciting tool for bioanalysis. However, the current attempts are mostly carried out in lab, and less explored in field. Here, a simple PEC aptasensor for E. coli O157:H7 was designed and optimized (LOD: 200 cfu/mL). To promote its field application, a portable PEC analyzer was further constructed with a miniaturized LED (3 V, 3 W) for excitation and a USB-type electrochemical workstation for detection. Meanwhile, a re-chargeable power bank (5 V, 20,000 mAh, originally used for cell phone charging) was explored to power the LED through a self-designed electrical circuit. In this manner, the PEC analyzer could work continuously for more than 12 h. To facilitate transportation or the portable PEC analyzer, all components were mounted into a suitcase (size: 42 × 34 × 17 cm 3 ; wight: ∼3.5 kg). To validate the applicability of the portable PEC analyzer, on-site detection of E. coli O157:H7 in an in-land river was carried out (> 8 h), demonstrating the bright potential of the portable PEC analyzer for field environmental monitoring.
研究领域:
生物分析
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环境监测
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食品与水安全
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产品关联
DOI
高影响因子
TALANTA
·
2025
·
IF 6.1
Luyang Zhao,Yang Song,Guoyang Xie,Hengyi Xu
A colorimetric assay based on the Fe/Al bimetallic organic framework NH 2 -MIL-53(Fe, Al) was developed for the sensitive detection of Escherichia coli O157:H7 ( E. coli O157:H7), a critical pathogen threatening food safety. The framework’s high specific surface area facilitated efficient antibody immobilization, whereas the incorporation of Al 3+ enhanced electron transfer between Fe 2+ /Fe 3+ , thereby significantly boosting peroxidase activity. The optimized NH 2 -MIL-53(Fe, Al) exhibited 1.4-fold and 4.9-fold higher relative absorbance than NH 2 -MIL-53(Fe) and NH 2 -MIL-53(Al), respectively. And it demonstrated 40-fold and 2-fold greater affinity for TMB and H 2 O 2 , respectively, compared to the natural enzyme. By integrating a dual-recognition system based on antibody and aptamer, the method enabled rapid detection with a limit of detection of 10 1 CFU/mL in colorimetric mode. Its successful application in complex matrices, including lettuce, juice, pool water, and chocolate milk, had yielded satisfactory recovery and precision, confirming its promising potential for food safety monitoring.
✓ 已验证
DOI
PubMed
高影响因子
INTERNATIONAL JOURNAL OF FOOD MICROBIOLOGY
·
2022
·
IF 5.911
Haiying Cui,Xiaojing Yang,Changzhu Li,Yong Ye,Xiaochen Chen,Lin Lin
Escherichia coli O157:H7 ( E. coli O157) is still one of the main pathogenic strains causing food poisoning. Here in, we established a strategy that can simultaneously remove free E. coli O157 and the biofilms it forms. Composite nanofiber (fP-NF) films were synthesized successfully by co-encapsulating E. coli O157 phages which isolated from domestic sewage and D -phenylalanine (D-Phe) into sodium alginate (SA)/polyethylene oxide (PEO) nanofibers by electrospinning. And dehydrated trehalose was added as a phage protectant. When SA:PEO is 3:9, the spinning solution has the optimum conductivity and viscosity, the average diameter of the obtained fP-NFs is 421.87 nm, and the mechanical strength and transparency of the fP-NF film are the best. The thermal stability of the fP-NF film was good, and the phage activity in the fiber was well preserved. The remaining population of phages in fP-NF membranes was still close to 10 6 PFU/mL after one week of placement, and the cumulative release efficiencies of phages at both room temperature (25 °C) and refrigerated storage temperature (4 °C) were above 70%. The antibacterial experiment showed that compared with the control group, the addition of D-Phe slightly enhanced the antibacterial activity of the nanofiber films against free E. coli O157, and the bactericidal rate within 8 h was 99.74%. On the other hand, D-Phe significantly enhanced the inhibitory activity of the nanofiber films against E. coli O157 biofilms, with the inhibition rate exceeding 99.99% within 72 h. The application results further confirmed that the addition of D-Phe could significantly enhance the inhibitory activity of nanofiber films on E. coli O157 proliferation and biofilm formation during short-term storage of beef and fruits and vegetables. It provides an important strategy and reference for the development of new active food packaging materials .
研究领域:
食品科学
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微生物学
·
材料科学
✓ 已验证
DOI
高影响因子
FOOD CHEMISTRY
·
2026
·
IF 10.4
Fengyang Wang,Panpan Liu,Yin Chen,Mengjuan Li,Yunlong Liu,Yan Qi,Xiaohui Xiong,Yuanjian Liu
Firstly, through various analytical methods, the mechanism by which the electrocatalytic oxygen reduction capacity of E. coli O157:H7 was enhanced under 4% NaCl stress was revealed. The cyclic voltammetry (CV) results indicated that the oxygen reduction ability of E. coli O157: H7 was improved under NaCl stress. Microbiological analysis confirmed the intracellular ROS levels in E. coli O157: H7 under NaCl stress is related to the upregulation of SOD/CAT activity. Metabolomics identified key metabolic adaptations in E. coli O157:H7, including enhanced tricarboxylic acid (TCA) cycles and ubiquinone (Q) biosynthesis, which promoted effective respiratory electron transfer in the bacteria. Secondly, the BPE-ECL (Bipolar Electrochemiluminescence) sensor designed based on 4% NaCl stress showed 9.72 times increase in anode ECL intensity. The detection limit was extremely low at 10 CFU for E. coli O157:H7 in 1 mL sample volume. This research provides a new solution for the sensitive screening of electrochemically active bacteria.
✓ 已验证
DOI
PubMed
高影响因子
SENSORS AND ACTUATORS B-CHEMICAL
·
2020
·
IF 7.1
Xiaoyan Zhang,Tingting Wu,Yuemeng Yang,Yongqiang Wen,Shutao Wang,Li-Ping Xu
Superwettable microchips exhibit excellent ability to anchor microdroplets and great potential in ultratrace sample detection. Herein, we present a superwettable electrochemical biosensor based on a dual-DNA walker strategy (dual-DW biosensor) for the attomolar detection of food-borne microorganisms ssDNA in microdroplets. In the presence of the target E. coli O157: H7 ssDNA, the blocked walking probe is activated as the first-step DNA walker. With the aid of the Nt.BsmAI nicking endonuclease, the partial sequence of the basal probe was released, thus achieving the first-step signal amplification. Then the hairpin probe 1(H1) was opened by the released basal probe and followed by the autonomous strand displacement of the ferrocene (Fc) labeled hairpin probe 2 (H2) and movement of the basal probe. Under optimized conditions, the dual-DNA walker strategy finally renders the dual-DW biosensor an ultrahigh sensitivity of 30 aM toward E. coli O157: H7 ssDNA and a broad detection linear range. The dual-DW biosensor also enables successful analysis of trace amount of E. coli O157: H7 ssDNA in real food samples. The superwettable electrochemical biosensor based on a dual-DNA walker strategy is expected to be a versatile tool for ultratrace DNA detection and be promising in food analysis.
研究领域:
生物化学
·
分析化学
·
食品科学
·
分子生物学
✓ 已验证
DOI
高影响因子
BIOSENSORS & BIOELECTRONICS
·
2020
·
IF 10.257
Ziqi Zhou,Yangzi Zhang,Mingzhang Guo,Kunlun Huang,Wentao Xu
A relatively-simple and high-efficient fluorescent magnetic biosensor based on DNAzyme was established for the detection of E. coli O157:H7. In order to solve the problem of weak signal and low sensitivity in the detection of foodborne pathogenic bacteria , we ingeniously designed a fluorescent sensor based on triple signal amplification of magnetic beads, DNAzyme and photoluminescence . In the detection process, the E. coli -specific RNA-cleaving DNAzyme can specifically identify the target protein in crude intracellular mixture (CIM), which caused its conformation changes and induced rolling circle amplification (RCA) to the generation and luminescence of copper nanoclusters (CuNCs). This cascade amplification design can capture weak signals in the sample. The biosensor also indicated a good linear range from 10 CFU mL −1 to 1000 CFU mL −1 and obtained a limit of detection (LOD) of 1.57 CFU mL −1 , which showed a relatively high sensitivity compared with other studies. Furthermore, the biosensor displayed high-efficient detection capability in 1.5 h and good reproducibility (relative standard deviations < 2%). It has been proved that this sensor is feasible to the detection of E. coli O157:H7 in drinking water and apple juice. Moreover, we found that the final detection product can effectively wrap the magnetic beads and can be driven by the magnetic field. And this unexpected discovery will provide ideas for the development of biosensing robots.
研究领域:
生物化学
·
食品科学
·
分子生物学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
FOOD CHEMISTRY
·
2024
·
IF 8.5
Lanqing Yang,Xiaomin Wang,Xu Jing,Baoqing Bai,Tao Bo,Jinhua Zhang,Ligang Yu,Hailong Qian,Ying Gu,Yukun Yang
Escherichia coli O157:H7 ( E. coli O157:H7 ) emerges as a foodborne pathogen, emphasizing the imperative for creating precise detection tools. An ultrasensitive electrochemiluminescence/fluorescence (ECL/FL) dual-signal mode aptasensor was constructed for the detection of E. coli O157:H7 . Ultrafine silver nanoparticles were loaded on the surface of hydrogen-bonded organic skeleton materials by in-situ photoreduction method, and then combined with aptamers that can identify specific targets to prepare HOF-101@AgNPs@Apt, greatly simplifying the ECL/FL dual-signal mode probe fabrication process and improving sensing reliability. HOF-101@AgNPs@Apt had both strong ECL luminescence and fluorescence, resulting in a high detection sensitivity. The low limit of detection (LOD) for ECL and FL were 0.48 CFU mL −1 and 2.39 CFU mL −1 , respectively. Moreover, the proposed dual-signal mode aptasensor has been successfully applied to determine E. coli O157:H7 levels in tap water and milk with superior accuracy and high antiinterference capability, providing a promising method for food safety monitoring.
研究领域:
食品科学
·
生物传感
·
分析化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Journal of Biomedical Nanotechnology
·
2009
·Vol. 5
·期 5
·505-510
·
IF 0.989
Li Zhiyang,He Lei,Shi Zhiyang,Wang Hua,Li Song,Liu Hongna,Wang Zhifei,He Nongyue
This paper described that Fe3O4 nanoparticles were encapsulated with methyl methacrylate (MMA) using linolenic acid (LA) as a crosslinking agent, after which the resulting polymethyl methacrylate (PMMA) embed Fe3O4 nanoparticles (PMMA/Fe3O4) were coated with silica, forming SiO2/(PMMA/Fe3O4) core–shell structure particles. Then these magnetic nanoparticles (MNPs) were applied in the developed system of chemiluminescent magnetic enzyme-linked immunoassay. E. coli O157:H7 was sandwiched between rabbits anti-E. coli O157:H7 polyclonal antibody-coated magnetite nanoparticles (immunomagnetic nanoparticles or IMNPs) and mouse anti-E. coli O157:H7 monoclonal antibody (E. coli O157-McAb). Commercial alkaline phosphatase conjugated horse anti-mouse immunoglobulin (ALP-Ab) was used to bond with the monoclonal antibody, finally the chemiluminescent signals were detected by adding 3-(2′-spiroadamantane)-4-methoxy-4-(3″-phosphoryloxy)phenyl-1,2-dioxetane (AMPPD) which was the substrate reagent of ALP. The specificity and sensitivity of this system for detecting E. coli O157:H7 were researched. The results indicated that this method was of good specificity when using E. coli Top 10F′ and Vibrio cholera as negative controls. The detection limit was 103 cells mL−1 when the antigen solution was 1 mL, and the procedure duration was about 3 h.
研究领域:
材料科学
·
纳米技术
·
生物技术
·
分析化学
·
微生物学
✓ 已验证
DOI
PubMed
高影响因子
危险品化学品经营许可证（带存储）