title: Enhancing the response of microbial fuel cell based toxicity sensors to Cu(II) with the applying of flow-through electrodes and controlled anode potentials.
abstract: The application of microbial fuel cell (MFC)-based toxicity sensors to real-world water monitoring is partly impeded by the limited sensitivity. To address this limitation, this study optimized the flow configurations and the control modes. Results revealed that the sensitivity increased by ∼15-41times with the applying of a flow-through anode, compared to those with a flow-by anode. The sensors operated in the controlled anode potential (CP) mode delivered better sensitivity than those operated in the constant external resistance (ER) mode over a broad range of anode potentials from -0.41V to +0.1V. Electrodeposition of Cu(II) was found to bias the toxicity measurement at low anode potentials. The optimal anode potential was approximately -0.15V, at which the sensor achieved an unbiased measurement of toxicity and the highest sensitivity. This value was greater than those required for electrodeposition while smaller than those for power overshoot.
authors.affiliation: State Key Joint Laboratory of Environment Simulation and Pollution Control School of Environment, Tsinghua University, Beijing 100084, PR China.
authors.forename: Yong
authors.initials: Y
authors.lastname: Jiang
authors.affiliation: State Key Joint Laboratory of Environment Simulation and Pollution Control School of Environment, Tsinghua University, Beijing 100084, PR China. Electronic address: liangpeng@tsinghua.edu.cn.
authors.forename: Peng
authors.initials: P
authors.lastname: Liang
authors.affiliation: State Key Joint Laboratory of Environment Simulation and Pollution Control School of Environment, Tsinghua University, Beijing 100084, PR China.
authors.forename: Changyong
authors.initials: C
authors.lastname: Zhang
authors.affiliation: State Key Joint Laboratory of Environment Simulation and Pollution Control School of Environment, Tsinghua University, Beijing 100084, PR China.
authors.forename: Yanhong
authors.initials: Y
authors.lastname: Bian
authors.affiliation: Division of Atmospheric Sciences, Desert Research Institute, Reno, NV 89512, USA.
authors.forename: Xufei
authors.initials: X
authors.lastname: Yang
authors.affiliation: State Key Joint Laboratory of Environment Simulation and Pollution Control School of Environment, Tsinghua University, Beijing 100084, PR China.
authors.forename: Xia
authors.initials: X
authors.lastname: Huang
authors.affiliation: Harvard University, Organismic and Evolutionary Biology, Cambridge, MA, USA.
authors.forename: Peter R
authors.initials: PR
authors.lastname: Girguis
mesh_terms: D018407:Bacterial Physiological Phenomena / Q000187:drug effects*; D001674:Bioelectric Energy Sources / Q000382:microbiology*; D001681:Biological Assay / Q000295:instrumentation*; D015374:Biosensing Techniques / Q000295:instrumentation; D003300:Copper / Q000032:analysis*; D004566:Electrodes; D004784:Environmental Monitoring / Q000295:instrumentation*; D004867:Equipment Design; D019544:Equipment Failure Analysis; D012212:Rheology / Q000295:instrumentation; D012680:Sensitivity and Specificity; D018675:Toxicity Tests / Q000295:instrumentation; D014874:Water Pollutants, Chemical / Q000032:analysis
chemical_list: D014874:Water Pollutants, Chemical; D003300:Copper
keywords: Biosensor; Cu(II); Flow-through; Microbial fuel cell; Sensitivity