Nanomaterial interfaces designed with different biorecognition elements for biosensing of key foodborne pathogens

Foodborne diseases caused by pathogen bacteria are a serious problem toward the safety of human life in a worldwide. Conventional methods for pathogen bacteria detection have several handicaps, including trained personnel requirement, low sensitivity, laborious enrichment steps, low selectivity, and long-term experiments. There is a need for precise and rapid identification and detection of foodborne pathogens. Biosensors are a remarkable alternative for the detection of foodborne bacteria compared to conventional methods. In recent years, there are different strategies for the designing of specific and sensitive biosensors. Researchers activated to develop enhanced biosensors with different transducer and recognition elements. Thus, the aim of this study was to provide a topical and detailed review on aptamer, nanofiber, and metal organic framework–based biosensors for the detection of food pathogens. First, the conventional methods, type of biosensors, common transducer, and recognition element were systematically explained. Then, novel signal amplification materials and nanomaterials were introduced. Last, current shortcomings were emphasized, and future alternatives were discussed.     

扬州市食品中7种食源性致病菌污染状况及耐药性研究

为确定易受污染的食品,研究食源性病原菌耐药性状,为制定HACCP控制食源性疾病提供科学依据,对扬州市食品中沙门菌、E.coliO157:H7、单核细胞增生李斯特菌、金黄色葡萄球菌、副溶血性弧菌、空肠弯曲菌和小肠结肠炎耶尔森菌污染状况进行分析。在957份食品中共检出沙门菌、单核细胞增生李斯特菌、金黄色葡萄球菌、副溶血性弧菌90株,检出率为9.40%。其中沙门菌检出率为2.09%,单核细胞增生李斯特菌检出率为4.49%,金黄色葡萄球菌检出率为2.72%,副溶血性弧菌检出率为0.10%,未检出E.coliO157:H7。在80件生肉类试样中检出空肠弯曲菌8株,小肠结肠炎耶尔森菌6株。对分离出的沙门菌、单核细胞增生李斯特菌、金黄色葡萄球菌进行药敏试验,结果表明3种致病菌对部分抗生素多重耐药。扬州市食品中主要危害因素为沙门菌、单核细胞增生李斯特菌、金黄色葡萄球菌及其对抗生素的多重耐药。食物链是病原菌耐药性产生的重要环节。加强生肉制品、散装熟食及生牛奶的卫生管理,控制动物饲料抗生素添加剂的使用并严格遵守休药期以防止耐药菌株的产生,对控制食源性疾病、保证食品安全具有很重要的意义。     

Point-of-Care Diagnostic Platforms for Loop-Mediated Isothermal Amplification

The loop-mediated isothermal amplification (LAMP) method is one of the Nucleic acid amplification tests (NAATs) that allows for the amplification of target regions without using a thermal cycle. With its unique primer design, LAMP ensures the rapid replication of the targeted DNA region with high specificity and high efficiency. LAMP technology is used for diagnostic purposes in pathogen detection due to its ease of use, low cost, and simplicity without requiring complex equipment. A wide range of LAMP diagnostic platforms have been developed for applications in bacteria, virus, and parasitic pathogen detection. Herein, the methodology of LAMP technology and its applications in pathogen detection and SNP genotyping and mutation detection are discussed. Point-of-care (PoC) LAMP platforms designed with the principles of microfluidic chip technology, including LAMP-on-a-chip, paper-based LAMP, and smartphone-based LAMP applications have been elaborated. LAMP technology represents a fast, robust, and reliable diagnostic platform for point-of-care testing.