He Binghuan, Zhang Fangzhou, Gong Pengfei, Sun Rui, Cheng Jianxin, Jin Chenghui, Liu Bo, Zhao Jianlong, Feng Shilun, Li Bei
School of Ophthalmology & Optometry, Eye Hospital, Wenzhou Medical University, Wenzhou, 325027, China; State Key Laboratory of Transducer Technology, Shanghai Institute of Microsystem and Information Technology, Chinese Academy of Sciences, Shanghai, 200050, China; Changchun Institute of Optics, Fine Mechanics and Physics, Chinese Academy of Sciences, Changchun, 130033, China.
Xiangfu Laboratory, Jiashan, 314100, China; State Key Laboratory of Transducer Technology, Shanghai Institute of Microsystem and Information Technology, Chinese Academy of Sciences, Shanghai, 200050, China.
Anal Chim Acta. 2025 Feb 8;1338:343571. doi: 10.1016/j.aca.2024.343571. Epub 2024 Dec 26.
Certain virulent strains of Escherichia coli (E. coli), notably the enterohemorrhagic serotype O157:H7, are recognized for causing diarrhea, gastroenteritis, and a range of illnesses that pose significant risks to public health and the safety of drinking water supplies. Early detection and management of E. coli, particularly at low concentrations, are critical for identifying potential sources of contamination. This proactive approach can prevent the spread of diseases, ensure the safety of drinking water, and maintain the hygiene of consumable products. However, detecting low concentrations of E. coli in water samples presents challenges, such as reduced sensitivity, prolonged analysis times, complex sample preparation, susceptibility to interferences, cost limitations, and result variability. To overcome these challenges, we developed an enrichment system that rapidly and efficiently concentrates low-concentration E. coli samples. This system consists of two modules: a primary enrichment module and a secondary enrichment module. The primary enrichment module uses Dean flow technology to enhance E. coli recovery through lateral flushing, achieving recovery rates between 82.7 % and 92.7 %. The secondary enrichment module employs double membrane filtration to further concentrate E. coli. This two-stage enrichment process can amplify E. coli concentrations up to 1000-fold, achieving a recovery rate of 61.8 % within just 30 min. This system enables ultra-high multiplicity enrichment of E. coli from low concentrations in water samples, providing small volumes of highly concentrated samples necessary for subsequent precise detection based on droplet microfluidic technology. The development of this system offers significant benefits for the enrichment and rapid detection of pathogenic bacteria in environmental samples.
某些致病性大肠杆菌菌株，特别是肠出血性血清型O157:H7，因可导致腹泻、肠胃炎以及一系列对公众健康和饮用水供应安全构成重大风险的疾病而为人所知。对大肠杆菌进行早期检测和管理，尤其是在低浓度情况下，对于识别潜在污染源至关重要。这种积极主动的方法可以预防疾病传播、确保饮用水安全并维持消费品的卫生状况。然而，检测水样中低浓度的大肠杆菌存在诸多挑战，如灵敏度降低、分析时间延长、样品制备复杂、易受干扰、成本限制以及结果变异性等。为克服这些挑战，我们开发了一种富集系统，可快速有效地浓缩低浓度大肠杆菌样本。该系统由两个模块组成：一级富集模块和二级富集模块。一级富集模块采用Dean流技术，通过侧向冲洗提高大肠杆菌的回收率，回收率在82.7%至92.7%之间。二级富集模块采用双膜过滤进一步浓缩大肠杆菌。这个两阶段的富集过程可将大肠杆菌浓度放大至1000倍，在短短30分钟内实现61.8%的回收率。该系统能够对水样中低浓度的大肠杆菌进行超高倍数富集，提供后续基于液滴微流控技术进行精确检测所需的少量高浓度样本。该系统的开发为环境样本中病原菌的富集和快速检测带来了显著益处。
