Detection of Salmonella spp. using microsphere-based, fiber-optic DNA microarrays
Detection of Salmonella spp. using microsphere-based, fiber-optic DNA microarrays
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DOI：
10.1021/ac0505270
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发表时间：
2005-08-01
影响因子：
7.4
通讯作者：
Walt, DR
中科院分区：
文献类型：
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作者：
Ahn, S;Walt, DR
沙门氏菌是公共卫生中最有问题的食物病原体之一，因为它们是与肉、家禽和鸡蛋污染有关的食物中毒的罪魁祸首。因此，需要对沙门氏菌进行快速、灵敏的检测，以确保食品安全。本研究采用微球固定的沙门氏菌invA和spvB基因寡核苷酸探针，将DNA探针功能化的微球（直径3.1 μ m）随机分布在蚀刻光纤束形成的微孔中，制备了用于检测沙门氏菌的光纤DNA微阵列。将探针功能化的微球与沙门氏菌DNA进行杂交，并使用cy3标记的二级探针在三明治式检测格式下进行可视化。在本研究中，杂交1 h后，无需额外扩增，即可检测到目标生物10(3)-10(4)cfu/mL。DNA芯片与其他常见的食物病原体（包括大肠杆菌和小肠结肠炎）没有交叉反应，甚至可以从细菌菌株的鸡尾酒中检测沙门氏菌，由于非特异性结合而仅适度丧失敏感性。该研究表明，光纤DNA微阵列可用于沙门氏菌的快速灵敏检测，由于光纤微阵列可以用不同的探针制备，这种方法也可以同时检测多种食品病原体。
Salmonella spp. are one of the most problematic food pathogens in public health, as they are responsible for food poisoning associated with contamination of meat, poultry, and eggs. Thus, rapid and sensitive detection of Salmonella spp. is required to ensure food safety. In this study, a fiber-optic DNA microarray using microsphere-immobilized oligonucleotide probes specific for the Salmonella invA and spvB genes was developed for detection of Salmonella spp. Microarrays were prepared by randomly distributing DNA probe-functionalized microspheres (3.1-mu m diameter) into microwells created by etching optical fiber bundles. Hybridization of the probe-functionalized microspheres to target DNA from Salmonella was performed and visualized using Cy3-labeled secondary probes in a sandwich-type assay format. In this study, 10(3)-10(4) cfu/mL of the target organism could be detected after 1-h hybridization without any additional amplification. The DNA microarray showed no cross-reactivity with other common food pathogens, including E. coli and Y. enterocolitica, and could even detect Salmonella spp. from cocktails of bacterial strains with only moderate loss of sensitivity due to nonspecific binding. This work suggests that fiber-optic DNA microarrays can be used for rapid and sensitive detection of Salmonella spp. Since fiber-optic microarrays can be prepared with different probes, this approach could also enable the simultaneous detection of multiple food pathogens.