纳米粒子在食源性致病菌检测中的应用进展

食品安全事关人民群众的身体健康和生命安全,而食源性致病菌是食品安全的主要影响因素。由食源性致病菌引起的疾病和死亡持续威胁着全球的公共卫生安全。因此,开发快速、准确且灵敏的食源性致病菌检测方法是预防食源性疾病暴发和确保食品安全的关键。常规检测方法费时费力,需要昂贵的设备和专业的人员,应用受限。近年来,随着纳米技术的快速发展,纳米粒子凭借其小尺寸、高比表面积和高反应活性等理化特性成为食源性致病菌检测领域的研究热点。此外,将识别元件修饰于纳米粒子表面并结合新颖的分析技术,能提高检测的特异性和灵敏度。该综述主要总结和比较了磁性纳米粒子、贵金属纳米粒子、荧光纳米粒子和二氧化硅纳米粒子在食源性致病菌检测中的应用,以期为食源性致病菌的快速分析提供思路。     

食源性致病菌的表面增强拉曼光谱检测技术研究进展

食源性致病菌引起的疾病的快速管控与预防是当前各国面临的食品安全监管难题之一,受到社会各界的广泛关注。目前常用的食源性致病菌检测方法存在步骤复杂、耗时、灵敏度低或选择性差等局限,发展快速、可靠的食源性致病菌检测方法仍是食品安全和公众健康的热点研究领域。表面增强拉曼光谱(SERS)作为一种新型的光谱快检技术,具有灵敏度高、选择性好、快速、无损检测等优点,在食源性致病菌检测方面表现出广阔的应用前景。该文简要介绍了SERS技术的背景、增强机制并总结了用于致病菌检测的活性纳米结构,全面综述了近5年来利用直接或间接SERS法以及SERS与其他技术结合检测食源性致病菌的研究进展,同时讨论了这些方法的优缺点。最后,提出当前SERS技术在实际应用中面临的挑战,并展望了SERS在食源性致病菌检测领域未来可能的发展趋势。     

基于抗菌肽的生物传感器在食源性致病菌检测中的应用

快速检测食源性致病菌是预防食源性疾病大量暴发的必要措施。基于生物传感器的食源性病原菌检测技术具有灵敏度高、实时定量、操作简便等优点。抗菌肽(antimicrobial peptides,AMPs)作为识别分子具有稳定性高和成本低的特点,在食源性致病菌的快速检测中得到了广泛的应用。将抗菌肽与生物传感器结合用于食源性致病菌具有潜在的实际应用价值。本文综述了基于抗菌肽的电化学方法和光学方法在食源性致病菌检测的应用,讨论了基于抗菌肽的高灵敏度和可靠检测平台的未来前景和挑战。     

食源性致病菌等温扩增检测技术的研究进展

快速可靠的食源性致病菌检测方法是保障食品安全的关键。然而,传统培养法的检测周期过于冗长,无法适应对时间敏感度较高的现场或在线检测。为此,研究人员开发了多种以快速和高灵敏度为主要特征的等温扩增技术及相应的检测产品,为食源性致病菌的现场或在线检测提供了强有力的技术支撑。该文对环介导等温扩增、滚环扩增、链置换扩增、切口酶信号扩增、核酸外切酶Ⅲ辅助扩增5种等温扩增方法的原理及其优缺点进行了梳理和比较。在此基础上,分析了等温扩增方法在细菌活性识别、非特异性扩增、前处理效率、检测通量4个方面所遇到的共性问题,并结合作者已有工作,提出了解决这些问题的方法或策略。     

表面增强拉曼光谱技术在快速、灵敏检测食源性致病菌中的应用

食源性致病菌的快速、灵敏检测是食品和药品安全领域关注的重点.表面增强拉曼光谱(SERS)技术凭借其检测速度快、信息丰富、灵敏度高、无损等优势在食源性致病菌的快速、灵敏检测中受到广泛关注.本文从SERS检测基底材料入手,综述了液相基底、刚性固相基底、柔性固相基底等材料的特点和性能,并对其在致病菌快速、灵敏检测中的应用进行...     

应用傅里叶变换红外光谱区分鉴定四种食源性致病菌的研究

利用傅里叶变换红外光谱技术(FT-IR)对大肠杆菌O157: H7、肠炎沙门氏菌、单核增生性李斯特菌、金黄色葡萄球菌这四种典型食源性致病菌进行了研究. 对其红外谱图进行基线校正和归一化处理, 对其谱带归属进行判别分析, 选取具有菌株特性的1500～800 cm^－1的谱带, 进行一阶导数运算, 结合化学计量学方法主成分分析(PCA)和聚类分析(CA), 并进行相关系数的统计学分析, 得出以下结果: 四种食源性致病菌最大相关系数为0.937, 最小相关系数为0.058, 而且四种不同的细菌在PCA和CA分析图上也达到了很好的区分效果. 研究表明, FT-IR有望成为一种快速检测食源性致病菌的新方法.     

沙门氏菌全细胞的热裂解气相色谱-质谱分析

本研究探讨了一种新型的快速检测食源性病原菌的方法。该方法应用热裂解气相色谱-质谱技术(pyrolysis-gas chromatography-mass spectrometry,Py-GC-MS)对食源性致病菌沙门氏菌进行了分析。通过对影响总离子流色谱图条件(热裂解条件、色谱条件、质谱条件)的研究,得到了满意的实验结果。结果表明:沙门氏菌全细胞在裂解温度600℃,时间为10s,离子源温度220℃,电离方式为EI,电离能为60eV的条件下可得到清晰的总离子流色谱图,同时对部分裂解产物的结构进行了鉴定。该方法快速、简便,可为研究快速鉴定致病菌提供新的技术手段。     

新型微流控芯片上鼠伤寒沙门氏菌的免疫捕获与原位荧光检测

食源性致病菌仍然严重影响人类健康,发展中国家情况更为严重,以沙门氏菌所引起的死亡为例,发展中国家的死亡率比发达国家高24%。而现有的细菌检测方法存在成本高、操作复杂或检测灵敏度不理想等缺陷,20世纪90年代发展起来的微流控芯片分析技术,以其独特的优势正逐步成为细胞/细菌的高效分析测试和研究平台。重庆大学化学化工学院徐溢教授课题组将微流控芯片分析技术、MEMS加工技术和纳米探针结合,开展细菌分离、检测、细菌浸染及其群     

基于显微共聚焦拉曼技术对三种食源性致病菌的快速鉴别研究

采用显微共聚焦拉曼技术,建立了对三种常见食源性致病菌快速鉴别的检测方法。使用XploRA PLUS共聚焦拉曼光谱仪,在激光功率为5 mW、积分时间为30s、积分次数为1次的条件下,对德尔卑沙门氏菌、副溶血性弧菌和金黄色葡萄球菌进行了拉曼光谱数据的采集。对拉曼光谱采用多项式平滑算法和荧光背底扣除后,采用主成分分析法(PCA)对预处理后的数据进行降维,提取出前三个主成分的累计方差贡献率达到了95.4％,样本明显的聚为了3类。同时结合Fisher判别分析法(FLD)构建分类模型,对三种样本进行交叉验证,分类准确率达到了100％。结果表明,采用显微共聚焦拉曼技术与PCA-FLD方法结合可实现对三种食源性致病菌的快速准确鉴别且模型检测精度高,方法具有一定的实用性及参考价值。     

万古霉素在食源性致病菌检测中的应用

食源性致病菌污染是引起食品安全的主要因素之一,对人类健康构成了严重威胁。万古霉素作为一种对革兰氏阳性菌具有特异性识别功能的小分子,能够修饰在磁性纳米粒子表面,使粒子获得靶向目标菌的能力,结合其他检测方法,可以实现分离检测革兰氏阳性菌的目的。本文对万古霉素功能化的磁珠在革兰氏阳性菌分离检测的研究进展进行了介绍,分析了万古霉素不同修饰方式和检测方法对其检测效果的影响,并对各种方法的检测结果进行了分析比较,最后,提出了万古霉素在食源性致病菌检测中存在的问题,并对其未来应用进行了展望。     

基于金属有机骨架材料的生物传感器在食源性致病菌或毒素检测中的应用

食源性致病菌或其产生的毒素污染的食物会给人体健康带来严重威胁,并造成巨大的经济损失。近年来,金属有机骨架材料(MOFs)作为一种新型的多孔晶体材料,因其具有大的表面积、高的孔隙率等特点,受到人们的广泛关注。将MOFs与生物传感器结合用于食源性致病菌或毒素的检测引起了研究者的兴趣。基于此,本文介绍了MOFs用于生物传感器的优势,概述了MOFs在不同的电化学和光学生物传感器的应用,综述了基于MOFs的生物传感器在致病菌或毒素的研究进展,讨论了基于MOFs的生物传感器在致病菌或毒素所面临的挑战和展望。     

Recent developments in rapid multiplexed bioanalytical methods for foodborne pathogenic bacteria detection

Foodborne illnesses caused by pathogenic bacteria represent a widespread and growing problem to public health, and there is an obvious need for rapid detection of food pathogens. Traditional culture-based techniques require tedious sample workup and are time-consuming. It is expected that new and more rapid methods can replace current techniques. To enable large scale screening procedures, new multiplex analytical formats are being developed, and these allow the detection and/or identification of more than one pathogen in a single analytical run, thus cutting assay times and costs. We review here recent advancements in the field of rapid multiplex analytical methods for foodborne pathogenic bacteria. A variety of strategies, such as multiplex polymerase chain reaction assays, microarray- or multichannel-based immunoassays, biosensors, and fingerprint-based approaches (such as mass spectrometry, electronic nose, or vibrational spectroscopic analysis of whole bacterial cells), have been explored. In addition, various technological solutions have been adopted to improve detectability and to eliminate interferences, although in most cases a brief pre-enrichment step is still required. This review also covers the progress, limitations and future challenges of these approaches and emphasizes the advantages of new separative techniques to selectively fractionate bacteria, thus increasing multiplexing capabilities and simplifying sample preparation procedures.

Electrochemical Detection of Pathogenic Bacteria—Recent Strategies,Advances and Challenges

Bacterial infections represent one of the leading causes of mortality worldwide, nevertheless the design and development of rapid, cost‐efficient and reliable detection methods for pathogens remains challenging. In recent years, electrochemical sensing methods have gained increasing attention for the detection of pathogenic bacteria, due to their increasingly competitive sensitivity. However, combining sensitivity with cost efficiency, high selectivity and a facile working procedure in a portable device is difficult. The presented review provides a summary of biosensing strategies for bacteria, published since 2015, by covering significant achievements towards custom‐designed portable point‐of‐care devices. Herein, the direct chemical recognition of bacteria via enzyme activity or secretion products, as well as their detection at various electrode surfaces and materials, such as nanomaterials, indium tin oxide or paper‐based immunosensors, is discussed. Furthermore, newly established hyphenated sensing principles, incorporated into lab‐on‐a‐chip and microfluidic devices, are presented and remaining technical challenges and limitations are considered.     

Recent advances in microchip electrophoresis for analysis of pathogenic bacteria and viruses

Life-threatening diseases, such as hepatitis B, pneumonia, tuberculosis, and COVID-19, are widespread due to pathogenic bacteria and viruses. Therefore, the development of highly sensitive, rapid, portable, cost-effective, and selective methods for the analysis of such microorganisms is a great challenge. Microchip electrophoresis (ME) has been widely used in recent years for the analysis of bacterial and viral pathogens in biological and environmental samples owing to its portability, simplicity, cost-effectiveness, and rapid analysis. However, microbial enrichment and purification are critical steps for accurate and sensitive analysis of pathogenic bacteria and viruses in complex matrices. Therefore, we first discussed the advances in the sample preparation technologies associated with the accurate analysis of such microorganisms, especially the on-chip microfluidic-based sample preparations such as dielectrophoresis and microfluidic membrane filtration. Thereafter, we focused on the recent advances in the lab-on-a-chip electrophoretic analysis of pathogenic bacteria and viruses in different complex matrices. As the microbial analysis is mainly based on the analysis of nucleic acid of the microorganism, the integration of nucleic acid-based amplification techniques such as polymerase chain reaction (PCR), quantitative PCR, and multiplex PCR with ME will result in an accurate and sensitive analysis of microbial pathogens. Such analyses are very important for the point-of-care diagnosis of various infectious diseases.     

Multiplex quantitative foodborne pathogen detection using high resolution CE-SSCP coupled stuffer-free multiplex ligation-dependent probe amplification

Sensitive multiplex detection methods for foodborne pathogens are important in controlling food safety, and detection of genetic markers is accepted to be one of the best tools for sensitive detection. Although CE technology offers great potential in terms of sensitive multiplex detection, the necessary amplification is confined to markers sharing common primers such as the 16S rRNA gene. For precise and sensitive detection, pathogen-specific genes are optimal markers. Although multiplex ligation-dependent probe amplification (MLPA) is appropriate for amplification of specific markers, the requirement for stuffers, to ensure length-dependent separation on CE, is a major obstacle in detection of foodborne pathogens. In the present study, we developed stuffer-free MLPA using high-resolution CE-SSCP to sensitively detect ten foodborne pathogens. The probe set for MLPA prior to CE-SSCP analysis was designed for species-specific detection. After careful optimization of each MLPA step, to ensure that CE-SSCP analysis was informative, we found that all ten pathogens could be reliably identified; the limits of detection were 0.5-5 pg of genomic DNA, and more than 100-fold increase could be quantitatively determined. Thus, MLPA-CE-SSCP is a sensitive and reliable technique for pathogen detection.     

Applications of Fruit Polyphenols and Their Functionalized Nanoparticles Against Foodborne Bacteria: A Mini Review

The ingestion of contaminated water and food is known to cause food illness. Moreover, on assessing the patients suffering from foodborne disease has revealed the role of microbes in such diseases. Concerning which different methods have been developed for protecting food from microbes, the treatment of food with chemicals has been reported to exhibit an unwanted organoleptic effect while also affecting the nutritional value of food. Owing to these challenges, the demand for natural food preservatives has substantially increased. Therefore, the interest of researchers and food industries has shifted towards fruit polyphenols as potent inhibitors of foodborne bacteria. Recently, numerous fruit polyphenols have been acclaimed for their ability to avert toxin production and biofilm formation. Furthermore, various studies have recommended using fruit polyphenols solely or in combination with chemical disinfectants and food preservatives. Currently, different nanoparticles have been synthesized using fruit polyphenols to curb the growth of pathogenic microbes. Hence, this review intends to summarize the current knowledge about fruit polyphenols as antibacterial agents against foodborne pathogens. Additionally, the application of different fruit extracts in synthesizing functionalized nanoparticles has also been discussed.