In this study, we established a versatile and simple magnetic-assisted microfluidic method for fast bacterial detection. Quantum dots (QDs) were loaded onto magnetic beads (MBs) to construct performance enhanced on-chip capture of bacteria. (), as a model bacterium was studied. CdSe QDs were deposited onto the surface of FeO MBs through layer-by-layer self-assembly to enhance the loading of antibodies (Abs). MBs functionalized with anti- antibody molecules in a micropillar-based microfluidic chip were utilized to capture , and matrix-assisted laser desorption ionization time-of-flight mass spectrometry (MALDI-TOF MS) was used for characterization of captured bacteria. This method was found capable of specifically isolating within the range of 1.0 to 1.0 × 10 CFU/mL, having a detection limit (LOD) of 10 CFU/mL. The average similarity score among mass spectra for the bacterial capture obtained in independent experiments is calculated as 0.97 ± 0.01 (n = 3), which shows this work's excellent reproducibility for bacterial capture. Bacterial growth on ready-to-eat (RTE) foods during its time of storage was successfully monitored. The present protocol has promising potential for microbial control and pathogen detection in the food industry.

中文翻译：

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量子点 (QD) 附加磁珠 (MB)，用于片上高效捕获和检测即食 (RTE) 食品中的细菌

在这项研究中，我们建立了一种通用且简单的磁辅助微流体方法，用于快速细菌检测。将量子点 (QD) 加载到磁珠 (MB) 上，以构建性能增强的细菌片上捕获。 ()，作为模式细菌进行了研究。通过层层自组装将 CdSe QD 沉积到 Fe3O MB 表面，以增强抗体 (Abs) 的负载。利用基于微柱的微流控芯片中带有抗抗体分子功能的MB来捕获细菌，并使用基质辅助激光解吸电离飞行时间质谱（MALDI-TOF MS）来表征捕获的细菌。该方法能够特异性分离 1.0 至 1.0 × 10 CFU/mL 范围内的细菌，检测限 (LOD) 为 10 CFU/mL。独立实验中获得的细菌捕获的质谱之间的平均相似性得分计算为 0.97 ± 0.01 (n = 3)，这表明这项工作对细菌捕获具有出色的重现性。成功监测了即食 (RTE) 食品在储存期间的细菌生长情况。本协议在食品工业中微生物控制和病原体检测方面具有广阔的前景。