Lin Xiaofeng, Liu Chenghao, Lei Qiaowen, Nan Xinru, Zhu Yunxiao, Liao Jing, Du Zhizhi, Ye Chenyi, Xiong Yixian, Yang Min, Fang Xiaojun, Luo Yan, Huang Qitong
Key Laboratory of Prevention and Treatment of Cardiovascular and Cerebrovascular Diseases of Ministry of Education, Jiangxi Provincial Key Laboratory of Tissue Engineering, Key Laboratory of Biomedical Sensors of Ganzhou, School of Medical and Information Engineering, School of Pharmacy, Scientific Research Center, Gannan Medical University, Ganzhou 341000, PR China.
Key Laboratory of Prevention and Treatment of Cardiovascular and Cerebrovascular Diseases of Ministry of Education, Jiangxi Provincial Key Laboratory of Tissue Engineering, Key Laboratory of Biomedical Sensors of Ganzhou, School of Medical and Information Engineering, School of Pharmacy, Scientific Research Center, Gannan Medical University, Ganzhou 341000, PR China; Department of Pharmacology and Toxicology, School of Pharmacy, University of Kansas, Lawrence, KS 66045, USA.
J Hazard Mater. 2025 Mar 5;485:136845. doi: 10.1016/j.jhazmat.2024.136845. Epub 2024 Dec 13.
The sensitive detection of Staphylococcus aureus (S. aureus) holds great practical importance for ensuring public health and food safety. In this study, a sensitivity and stability ratiometric electrochemical aptasensor using graphene quantum dots/[Cu (benzotriazole-5-COO) (benzotriazole-5-COOH) (μ-Cl) (μ-OH)-(HO)]·3 HO nanocomposite (GQDs/Cu-MOF) was constructed for S. aureus detection. The GQDs enhanced the sensitivity of the electrochemical aptasensor due to their excellent conductivity and provided stability through their abundant carboxyl groups. The Cu-MOF, possessing electrical activity, not only enhanced the performance of the electrochemical aptasensor but also served as a signal label. The single-stranded DNA1 (S1) was immobilized on the surface of a GQDs/Cu-MOF/screen-printed carbon electrode (S1/GQDs/Cu-MOF/SPCE) as the sensing interface. Subsequently, the S1/GQDs/Cu-MOF/SPCE was hybridized with the probe DNA-ferrocene (S2-Fc), resulting in the generation of electrochemical signals from Cu-MOF (I) and S2-ferrocene (I) within the system. However, the electron transfer performance of DNA at the sensing interface was compromised, leading to a reduction in the I. When S. aureus was present in the system, S2-Fc reacted with it and detached from the sensing surface, resulting in a gradual decrease in I and an increase in I. Then a ratiometric electrochemical aptasensor was established for S. aureus detection with remarkable sensitivity (0.97 CFU·mL), excellent stability, and a broad linear range. Furthermore, the aptasensor was successfully applied to detect S. aureus in tap water, milk, Lonicera japonica, urine, and Zhangjiang River. Additionally, this aptasensor design can be adapted for the detection of other foodborne pathogens, which indicates that the design scheme of the aptasensor has good universality.
金黄色葡萄球菌（S. aureus）的灵敏检测对于确保公共卫生和食品安全具有重大实际意义。在本研究中，构建了一种基于石墨烯量子点/[Cu (苯并三唑 - 5 - COO)(苯并三唑 - 5 - COOH)(μ - Cl)(μ - OH)-(HO)]·3 HO纳米复合材料（GQDs/Cu - MOF）的灵敏且稳定的比率型电化学适配体传感器用于金黄色葡萄球菌检测。石墨烯量子点因其优异的导电性提高了电化学适配体传感器的灵敏度，并通过其丰富的羧基提供稳定性。具有电活性的Cu - MOF不仅增强了电化学适配体传感器的性能，还用作信号标记。单链DNA1（S1）固定在GQDs/Cu - MOF/丝网印刷碳电极（S1/GQDs/Cu - MOF/SPCE）表面作为传感界面。随后，S1/GQDs/Cu - MOF/SPCE与探针DNA - 二茂铁（S2 - Fc）杂交，导致系统内Cu - MOF（I）和S2 - 二茂铁（I）产生电化学信号。然而，DNA在传感界面的电子转移性能受到影响，导致I降低。当系统中存在金黄色葡萄球菌时，S2 - Fc与之反应并从传感表面脱离，导致I逐渐降低且I增加。然后建立了一种用于金黄色葡萄球菌检测的比率型电化学适配体传感器，具有显著的灵敏度（0.97 CFU·mL）、优异的稳定性和较宽的线性范围。此外，该适配体传感器成功应用于检测自来水、牛奶、金银花、尿液和漳江中的金黄色葡萄球菌。此外，这种适配体传感器设计可适用于检测其他食源性病原体，这表明适配体传感器的设计方案具有良好的通用性。
