Jiangsu Engineering Laboratory of Smart Carbon-Rich Materials and Device, Laboratory of Environmental Medicine Engineering, Ministry of Education, School of Chemistry and Chemical Engineering, Southeast University, Nanjing 211189, China.
Coll Food Sci & Light Ind, Nanjing Tech University, Nanjing 211800, China.
Food Chem. 2022 Jul 30;383:132404. doi: 10.1016/j.foodchem.2022.132404. Epub 2022 Feb 10.
An Ag@C hybrid bipolar electrode (BPE) sensing platform has been established for the temporal detection of Staphylococcus aureus (S. aureus) in food. Combining the advantages of anodic dissolution of Ag and cathodic biocatalysis of oxygen (O) reduction, this strategy showed an ultralow detection limit down to 10 CFU mL. As the formation of Ag@C completely quenched the electrochemiluminescence (ECL) emission of luminol, the ECL emission recovery reflected the extent of anodic dissolution. Meanwhile, S. aureus catalyzed the electrochemical reduction of O at the cathode, reducing the overpotential for cathodic O reduction and thus increasing the rate of anodic electron loss, facilitating Ag dissolution and restoring the ECL emission of luminol. When a constant potential was applied, through monitoring the ECL recovery time before and after the incubation of S. aureus on the cathode, S. aureus could be quantified due to the slight difference of the conductivity.
一种 Ag@C 杂化双极电极 (BPE) 传感平台已被建立用于食品中金黄色葡萄球菌 (S. aureus) 的时间检测。该策略结合了 Ag 的阳极溶解和氧 (O) 还原的阴极生物催化的优势，其检测下限低至 10 CFU mL。由于 Ag@C 的形成完全猝灭了鲁米诺的电化学发光 (ECL) 发射，因此 ECL 发射恢复反映了阳极溶解的程度。同时，金黄色葡萄球菌在阴极催化 O 的电化学还原，降低了阴极 O 还原的超电势，从而增加了阳极电子损失的速率，促进了 Ag 的溶解并恢复了鲁米诺的 ECL 发射。当施加恒电位时，通过监测金黄色葡萄球菌在阴极孵育前后的 ECL 恢复时间，可以定量金黄色葡萄球菌，因为其电导率略有差异。
