State Key Laboratory of Lake Science and Environment, Nanjing Institute of Geography and Limnology, Chinese Academy of Sciences, Nanjing 210008, China.
Faculty of Resources and Environmental Science, Hubei University, Wuhan 430062, China.
Sci Total Environ. 2019 Jul 10;673:272-280. doi: 10.1016/j.scitotenv.2019.04.032. Epub 2019 Apr 3.
A novel multi-cathode, single-anode system integrating a sediment microbial fuel cell -based biosensor was developed for in-situ, continuous, and online monitoring of dissolved oxygen (DO) concentrations along various depths of lake water. The signal feedback mechanism was evaluated based on a relationship between voltage and DO concentration at corresponding depths. With an external resistance of 1000 Ω, a linear relationship was found (regression coefficient, R = 0.9576) between voltage and DO in the range of 0-9 mg L. The sensor performance was further optimized under various influence factors. The results of indoor experiments indicated that the optimal anode to single cathode area ratio was 11:1. The sensor signal could also be significantly influenced by organic matter content in sediment; thus, the addition of 5% organic matter could obtain a stable anode potential and a high voltage output. Furthermore, the sensor was operated in-situ for 67 days in a lake environment, which also led to a good correlation between the voltage and DO (R = 0.8897). Thus, this integrated system has great potential as an early-warning program to help identify environmental risks in aquatic environments.
开发了一种新型的多阴极、单阳极系统，集成了基于沉积物微生物燃料电池的生物传感器，用于原位、连续和在线监测湖水不同深度的溶解氧 (DO) 浓度。基于相应深度的电压和 DO 浓度之间的关系，评估了信号反馈机制。在外阻为 1000 Ω 的情况下，发现电压和 DO 之间在 0-9 mg/L 的范围内存在线性关系（回归系数，R=0.9576）。在各种影响因素下进一步优化了传感器性能。室内实验结果表明，阳极到单阴极的最佳面积比为 11:1。传感器信号也会受到沉积物中有机物含量的显著影响；因此，添加 5%的有机物可以获得稳定的阳极电位和高电压输出。此外，该传感器在湖泊环境中现场运行了 67 天，这也导致了电压和 DO 之间的良好相关性（R=0.8897）。因此，该集成系统具有作为预警程序的巨大潜力，有助于识别水生环境中的环境风险。
