Department of Chemistry, Colorado State University, Fort Collins, Colorado 80523, United States.
Anal Chem. 2012 Mar 20;84(6):2900-7. doi: 10.1021/ac203466y. Epub 2012 Mar 6.
Foodborne pathogens are a major public health threat and financial burden for the food industry, individuals, and society, with an estimated 76 million cases of food-related illness occurring in the United States alone each year. Three of the most important causative bacterial agents of foodborne diseases are pathogenic strains of Escherichia coli , Salmonella spp., and Listeria monocytogenes , due to the severity and frequency of illness and disproportionally high number of fatalities. Their continued persistence in food has dictated the ongoing need for faster, simpler, and less expensive analytical systems capable of live pathogen detection in complex samples. Culture techniques for detection and identification of foodborne pathogens require 5-7 days to complete. Major improvements to molecular detection techniques have been introduced recently, including polymerase chain reaction (PCR). These methods can be tedious; require complex, expensive instrumentation; necessitate highly trained personnel; and are not easily amenable to routine screening. Here, a paper-based analytical device (μPAD) has been developed for the detection of E. coli O157:H7, Salmonella Typhimurium, and L. monocytogenes in food samples as a screening system. In this work, a paper-based microspot assay was created by use of wax printing on filter paper. Detection is achieved by measuring the color change when an enzyme associated with the pathogen of interest reacts with a chromogenic substrate. When combined with enrichment procedures, the method allows for an enrichment time of 12 h or less and is capable of detecting bacteria in concentrations in inoculated ready-to-eat (RTE) meat as low as 10(1) colony-forming units/cm(2).
食源性病原体是对公众健康的重大威胁，也是食品行业、个人和社会的沉重经济负担。仅在美国，每年就约有 7600 万例与食物有关的疾病。由于疾病的严重程度和发生频率以及不成比例的高死亡率，三种最重要的食源性疾病病原体细菌是致病性大肠杆菌、沙门氏菌和单增李斯特菌。由于这些病原体在食品中的持续存在，因此需要不断开发更快、更简单、更经济的分析系统，以实现对复杂样本中活病原体的检测。用于检测和鉴定食源性病原体的培养技术需要 5-7 天才能完成。最近已经引入了主要的分子检测技术改进，包括聚合酶链反应（PCR）。这些方法可能很繁琐；需要复杂、昂贵的仪器；需要高度训练有素的人员；并且不容易进行常规筛查。在这里，已经开发了一种基于纸张的分析设备（μPAD），作为一种筛选系统，用于检测食物样本中的大肠杆菌 O157:H7、鼠伤寒沙门氏菌和单核细胞增生李斯特菌。在这项工作中，通过在滤纸上使用蜡印创建了基于纸张的微点分析。通过测量与感兴趣的病原体相关的酶与显色底物反应时的颜色变化来进行检测。当与富集程序结合使用时，该方法允许富集时间不超过 12 小时，并能够检测接种即食（RTE）肉中低至 10（1）菌落形成单位/cm（2）的细菌。
