Ouyang Qin, Wang Baoning, Ahmad Waqas, Yang Yongcun, Chen Quansheng
School of Food and Biological Engineering, Jiangsu University, Zhenjiang, 212013, People's Republic of China.
Anal Bioanal Chem. 2022 Dec;414(29-30):8179-8189. doi: 10.1007/s00216-022-04352-5. Epub 2022 Oct 5.
Staphylococcus aureus (S. aureus) is a common pathogen that is dangerous to humans' health. Herein, a novel upconversion fluorescent biosensor based on fluorescence resonance energy transfer from aptamer-labeled upconversion nanoparticles (UCNPs-apt) as donor and cobalt oxyhydroxide (CoOOH) nanosheets as acceptor was designed to detect S. aureus in complex matrices. The principle of the work relies on fluorescence resonance energy transfer as UCNPs-apt can self-assemble on CoOOH nanosheet surfaces by van der Waals forces to effectively quench the fluorescence. When S. aureus was added, the aptamer was able to preferentially capture the target, resulting in the dissociation of donor and acceptor and the recovery of fluorescence. The structure and morphology of the nanostructures were assigned in detail by a series of characterizations, and the energy transfer mechanism was evaluated by time-resolved lifetime measurements. Under the optimal conditions, a linear calibration plot was obtained in a concentration range of 45-4.5 × 10 CFU/mL with a limit of detection of 15 CFU/mL. In addition, the proposed biosensor was used for S. aureus detection in real samples (e.g., pork, beef), and the detection result showed no significant difference (p > 0.05) compared with the conventional plate count approach. Hence, the fabricated biosensor holds a potential application for S. aureus in food analysis and public health.
金黄色葡萄球菌是一种对人类健康有害的常见病原体。在此，设计了一种基于荧光共振能量转移的新型上转换荧光生物传感器，以适配体标记的上转换纳米颗粒（UCNPs-apt）作为供体，氢氧化钴（CoOOH）纳米片作为受体，用于检测复杂基质中的金黄色葡萄球菌。该工作原理基于荧光共振能量转移，因为UCNPs-apt可以通过范德华力自组装在CoOOH纳米片表面，从而有效猝灭荧光。当加入金黄色葡萄球菌时，适配体能够优先捕获目标，导致供体和受体解离，荧光恢复。通过一系列表征详细确定了纳米结构的结构和形态，并通过时间分辨寿命测量评估了能量转移机制。在最佳条件下，在45-4.5×10 CFU/mL的浓度范围内获得了线性校准曲线，检测限为15 CFU/mL。此外，所提出的生物传感器用于实际样品（如猪肉、牛肉）中金黄色葡萄球菌的检测，检测结果与传统平板计数法相比无显著差异（p＞0.05）。因此，制备的生物传感器在食品分析和公共卫生中对金黄色葡萄球菌具有潜在的应用价值。
