Staphylococcus aureus is one of the most important food-borne bacterial pathogens and causes numerous illnesses. In this work, we report a sensitive and highly selective magnetic-aptamer biosensor based on a personal glucose meter (PGM) platform for the detection of Staphylococcus aureus. The aptamer for Staphylococcus aureus was immobilized on the magnetic bead by hybridization with the capture probe P. In the presence of Staphylococcus aureus, the aptamer was dissociated from the magnetic bead. Then the capture probe was exposed and could be hybridized with a biotinylated probe to trigger the DNA hybridization chain reaction (HCR), thus achieving the signal amplification. The concentration of streptavidin-labeled invertase can be read by PGM, thus can lead to the portable quantitative detection of Staphylococcus aureus. After optimization of various conditions, 5 μM probe P, the MB-P reaction time for 36 h, the competition time for 60 min, 0.5 μM H1 & H2, 0.5 M sucrose and the sucrose invertase catalytic reaction time for 50 min was chosen to achieve the better sensor performance. Under the optimal conditions, the fabricated sensor offers high sensitivity with the limit of detection about 2 CFU/mL. This sensitive PGM based sensor could successfully evaluate the Staphylococcus aureus concentration in real food samples, and the results are consistent with those obtained by using plate counting methods. Moreover, the PGM sensor can greatly reduce the required time compared to the plate counting methods. The fabricated sensor supplies an ideal solution for rapid portable detection of bacterial pathogens and holds its potential use in the quality control for agriculture and food enterprises, entry-exit inspection and quality testing for food.

金黄色葡萄球菌是最重要的食源性细菌病原体之一，并引起多种疾病。在这项工作中，我们报告了一种基于个人血糖仪（PGM）平台的敏感且高度选择性的磁性适体生物传感器，用于检测金黄色葡萄球菌。通过与捕获探针P杂交，将金黄色葡萄球菌的适体固定在磁珠上。在金黄色葡萄球菌的存在下，适体从磁珠解离。然后将捕获探针暴露，并可以与生物素化探针杂交以触发DNA杂交链反应（HCR），从而实现信号放大。PGM可以读取链霉亲和素标记的转化酶的浓度，从而可以便携式定量检测金黄色葡萄球菌。在优化各种条件后，选择5μM探针P，MB-P反应时间为36 h，竞争时间为60 min，0.5μMH1和H2、0.5 M蔗糖以及蔗糖转化酶催化反应时间为50 min进行选择。实现更好的传感器性能。在最佳条件下，制成的传感器具有很高的灵敏度，检测极限约为2 CFU / mL。这种基于PGM的灵敏传感器可以成功评估金黄色葡萄球菌在真实食品样品中的浓度，结果与使用平板计数法获得的结果一致。而且，与板计数方法相比，PGM传感器可以大大减少所需的时间。制成的传感器为细菌病原体的快速便携式检测提供了理想的解决方案，并在农业和食品企业的质量控制，出入境检查和食品质量测试中具有潜在的用途。