Anodic biofilms as the interphase for electroactive bacterial growth on carbon veil.
The structure and activity of electrochemically active biofilms (EABs) are usually investigated on flat electrodes. However, real world applications such as wastewater treatment and bioelectrosynthesis require tridimensional electrodes to increase surface area and facilitate EAB attachment. The structure and activity of thick EABs grown on high surface area electrodes are difficult to characterize with electrochemical and microscopy methods. Here, the authors adopt a stacked electrode configuration to simulate the high surface and the tridimensional structure of an electrode for large-scale EAB applications. Each layer of the stacked electrode is independently characterized using confocal laser scanning microscopy (CLSM) and digital image processing. Shewanella oneidensis MR-1 biofilm on stacked carbon veil electrodes is grown under constant oxidative potentials (0, +200, and +400 mV versus Ag/AgCl) until a stable current output is obtained. The textural, aerial, and volumetric parameters extracted from CLSM images allow tracking of the evolution of morphological properties within the stacked electrodes. The electrode layers facing the bulk liquid show higher biovolumes compared with the inner layer of the stack. The electrochemical performance of S. oneidensis MR-1 is directly linked to the overall biofilm volume as well as connectivity between cell clusters.
Department of Chemical and Biological Engineering, Center for Micro-Engineered Materials (CMEM), University of New Mexico, Albuquerque, New Mexico 87131.
Kateryna
K
Artyushkova
Singapore Centre for Environmental Life Sciences Engineering (SCELSE), Nanyang Technological University, 60 Nanyang Drive, Singapore 637551 and Interdisciplinary Graduate School, Nanyang Technological University, Singapore 639798.
Dan
D
Roizman
Singapore Centre for Environmental Life Sciences Engineering (SCELSE), Nanyang Technological University, 60 Nanyang Drive, Singapore 637551.
Carlo
C
Santoro
Singapore Centre for Environmental Life Sciences Engineering (SCELSE), Nanyang Technological University, 60 Nanyang Drive, Singapore 637551 and Interdisciplinary Graduate School, Nanyang Technological University, Singapore 639798.
Lucinda Elizabeth
LE
Doyle
Singapore Centre for Environmental Life Sciences Engineering (SCELSE), Nanyang Technological University, 60 Nanyang Drive, Singapore 637551.
Abeed
A
Fatima Mohidin
Department of Chemical and Biological Engineering, Center for Micro-Engineered Materials (CMEM), University of New Mexico, Albuquerque, New Mexico 87131.
Plamen
P
Atanassov
Singapore Centre for Environmental Life Sciences Engineering (SCELSE), Nanyang Technological University, 60 Nanyang Drive, Singapore 637551 and School of Chemical and Biomedical Engineering, 62 Nanyang Drive, Singapore 637459.
Enrico
E
Marsili
D001674:Bioelectric Energy Sources; D018441:Biofilms / Q000254:growth & development*; D002244:Carbon; D004566:Electrodes / Q000382:microbiology*; D007091:Image Processing, Computer-Assisted; D018613:Microscopy, Confocal; D020592:Shewanella / Q000254:growth & development / Q000502:physiology*
D002244:Carbon