Chongqing Institute of Green and Intelligent Technology, Chinese Academy of Sciences, Chongqing 400714, China; School of Civil Engineering, Architecture and Environment, Xihua University, Chengdu 610039, China.
Chongqing Institute of Green and Intelligent Technology, Chinese Academy of Sciences, Chongqing 400714, China; Key Laboratory of Reservoir Aquatic Environment, Chinese Academy of Sciences, Chongqing 400714, China.
Sci Total Environ. 2021 Jan 20;753:142244. doi: 10.1016/j.scitotenv.2020.142244. Epub 2020 Sep 7.
Microbial fuel cell (MFC) biosensors have been suggested as an alternative detection method for biochemical oxygen demand (BOD). However, it is absolutely essential to develop maintenance procedures for MFC biosensors` because in practice the lay-up period cannot be avoided. In this work, setting electroactive bacteria (EAB) under hibernation condition was demonstrated to be a feasible maintenance method, which provided important insights into the flexible and robust BOD detection using MFC biosensors. Standard BOD solution containing 500, 200, and 20 mg/L BOD were used to evaluate the detection performance after EAB hibernations. Results demonstrated quick recovery of voltage output and high-accuracy BOD detection after hibernations up to 30 days in MFC biosensors detecting 500 mg/L and 200 mg/L BOD. Identical anode potentials after the EAB hibernations suggested intact bacterial ability of current generation. Non-turnover cyclic voltammetry immediately collected after the hibernations suggested multiple redox couples and the presence of cytochromes that played key roles in EAB metabolism and functioned as temporary electron sinks during the hibernations, leading to the increased detected BOD concentration in the restarting cycles. Generally, setting EAB under hibernation condition is a simple and convenient maintenance method for MFC-based BOD biosensors, which not only provides insights into flexible and robust BOD detection, but also be helpful for other MFC biosensing instruments.
微生物燃料电池（MFC）生物传感器已被提议作为生化需氧量（BOD）的替代检测方法。然而，开发 MFC 生物传感器的维护程序是绝对必要的，因为在实践中无法避免搁置期。在这项工作中，证明将电活性细菌（EAB）置于休眠状态是一种可行的维护方法，这为使用 MFC 生物传感器进行灵活和稳健的 BOD 检测提供了重要的见解。使用标准的 BOD 溶液，其中包含 500、200 和 20 mg/L 的 BOD，评估 EAB 休眠后对 500 mg/L 和 200 mg/L BOD 的检测性能。结果表明，在检测 500 mg/L 和 200 mg/L BOD 的 MFC 生物传感器中，EAB 休眠长达 30 天后，电压输出能够快速恢复，并且具有高精度的 BOD 检测能力。EAB 休眠后的阳极电位相同表明电流产生的细菌能力完好无损。休眠后立即采集的非循环伏安法表明存在多种氧化还原对和细胞色素，它们在 EAB 代谢中起着关键作用，并在休眠期间充当临时电子汇，导致在重新启动循环中检测到的 BOD 浓度增加。一般来说，将 EAB 置于休眠状态是一种简单方便的 MFC 基 BOD 生物传感器的维护方法，不仅为灵活和稳健的 BOD 检测提供了见解，而且对其他 MFC 生物传感仪器也有帮助。
