Discover insights from thousands of peer-reviewed papers on microbial electrochemical systems
Daniel R. Bond, Dawn E. Holmes, Leonard M. Tender et al.
Science · 2002
Energy in the form of electricity can be harvested from marine sediments by placing a graphite electrode (the anode) in the anoxic zone and connecting it to a graphite cathode in the overlying aerobic water. We report a specific enrichment of microorganisms of the family Geobacteraceae on energy-harvesting anodes, and we show that these microorganisms can conserve energy to support their growth by oxidizing organic compounds with an electrode serving as the sole electron acceptor. This finding not only provides a method for extracting energy from organic matter, but also suggests a strategy for promoting the bioremediation of organic contaminants in subsurface environments.
Hermann J. Eberl, Cristian Picioreanu, J. J. Heijnen et al.
Chemical Engineering Science · 2000
Junghyun Kim, Han-Shin Kim, Sewoon Han et al.
Lab on a Chip · 2013
In aquatic environments, microorganisms tend to form biofilms on surfaces to protect them from harsh conditions. The biofilms then accumulate into multilayered mat-like structures. In this study, we evaluated the effects of the hydrodynamic conditions on the ecology of biofilms produced by Pseudomonas aeruginosa (PA14). In microfluidic channels, we found that the development of biofilms was regulated by hydrodynamic conditions, but the developed biofilms also changed flow velocity by narrowing flow width. The coupled growing conditions were simplified by a new concept of consequent variables, and the dimensionless biofilm development (Ab/h(2) & Ab/w(cs)(2)) was successfully expressed by the Reynolds number (Re) and the dimension of the channel (r). At low Re, higher flow rates encouraged growth of biofilms, while higher flow rates with high Re suppressed growth of biofilms. These results provide a simple model as a theoretical basis for understanding development of biofilms in microfluidic channels.
Ruggero Rossi, Bruce E. Logan
Electrochimica Acta · 2020
Sangam Srikanth, Jaligam Murali Mohan, Sushil Raut et al.
Sensors and Actuators A: Physical · 2021
Joseph Wang, Ronen Polsky, Baomin Tian et al.
Analytical Chemistry · 2000
Microfluidic chip devices are shown to be attractive platforms for performing microscale voltammetric analysis and for integrating voltammetric procedures with on-chip chemical reactions and fluid manipulations. Linear-sweep, square-wave, and adsorptive-stripping voltammograms are recorded while electrokinetically "pumping" the sample through the microchannels. The adaptation of voltammetric techniques to microfluidic chip operation requires an assessment of the effect of relevant experimental variables, particularly the high voltage used for driving the electroosmotic flow, upon the background current, potential window, and size or potential of the voltammetric signal. The exact potential window of the chip detector is dependent upon the driving voltage. Manipulation of the electroosmotic flow opens the door to hydrodynamic modulation (stopped-flow) and reversed-flow operations. The modulated analyte velocity permits compensation of the microchip voltammetric background. Reversal of the driving voltage polarity offers extended residence times in the detector compartment. Rapid square-wave voltammetry/flow injection operation allows a detection limit of 2 x 10(-12) mol (i.e., 2 pmol) of 2,4,6-trinitrotoluene (TNT) in connection with 47 nL of injected sample. The ability of integrating chemical reactions with voltammetric detection is demonstrated for adsorptive stripping measurements of trace nickel using the nickel-dimethylglyoxime model system. The voltammetric response is characterized using catechol, hydrazine, TNT, and nickel as test species. The ability to perform on-chip voltammertic protocols in advantageous over nanovial voltammetric operations that lack a liquid-handling capability. Coupling the versatility of microfluidic chips with the rich information content of voltammetry thus opens an array of future opportunities.
Stéphane Pinck, Lucila Martínez Ostormujof, Sébastien Teychené et al.
Microorganisms · 2020
It is the ambition of many researchers to finally be able to close in on the fundamental, coupled phenomena that occur during the formation and expression of electrocatalytic activity in electroactive biofilms. It is because of this desire to understand that bioelectrochemical systems (BESs) have been miniaturized into microBES by taking advantage of the worldwide development of microfluidics. Microfluidics tools applied to bioelectrochemistry permit even more fundamental studies of interactions and coupled phenomena occurring at the microscale, thanks, in particular, to the concomitant combination of electroanalysis, spectroscopic analytical techniques and real-time microscopy that is now possible. The analytical microsystem is therefore much better suited to the monitoring, not only of electroactive biofilm formation but also of the expression and disentangling of extracellular electron transfer (EET) catalytic mechanisms. This article reviews the details of the configurations of microfluidic BESs designed for selected objectives and their microfabrication techniques. Because the aim is to manipulate microvolumes and due to the high modularity of the experimental systems, the interfacial conditions between electrodes and electrolytes are perfectly controlled in terms of physicochemistry (pH, nutrients, chemical effectors, etc.) and hydrodynamics (shear, material transport, etc.). Most of the theoretical advances have been obtained thanks to work carried out using models of electroactive bacteria monocultures, mainly to simplify biological investigation systems. However, a huge virgin field of investigation still remains to be explored by taking advantage of the capacities of microfluidic BESs regarding the complexity and interactions of mixed electroactive biofilms.
Mir Pouyan Zarabadi, Steve J. Charette, Jesse Greener
ChemElectroChem · 2018
Abstract Biofilms from Geobacter sulfurreducens are promising materials for new bioelectrochemical systems. To improve the performance of such systems, limitations related to biofilm acidification should be addressed. This work examines a long‐held assumption that liquid flow can deacidify biofilm pH by enhancing molecular mass transport in the biofilm subdomain. A microfluidic electrochemical system was used to measure changes to biofilm pH in situ while accurately modulating hydrodynamic conditions under turnover, nutrient‐limited and starvation conditions. We discovered that increased flow rates could indeed mitigate biofilm acidification, but not under turnover concentrations, which are the predominant conditions used in research studies. This effect is demonstrated with the observation that relative increases to bio‐current under increased flow rates were stronger for experiments conducted under nutrient‐limited concentrations compared to turnover concentrations. This can open the way for a solution to poor performance of some bioelectrochemical systems at low concentrations.
Feng Zhao, Robert C. T. Slade, John R. Varcoe
Chemical Society Reviews · 2009
Microbial fuel cells (MFCs) represent a clean and renewable energy resource. To date, power generation in MFCs is severely limited. In order to improve performance, a wide range of techniques have been utilised for a fundamental scientific understanding of the components and processes and also to investigate MFC performance bottlenecks. In this tutorial review, we discuss the electrochemical/electroanalytical techniques employed in recent MFC studies and discusses the principles, experimental implementation, data processing requirements, capabilities, and weaknesses of these techniques.
Vincent Mirallès, Axel Huerre, Florent Malloggi et al.
Diagnostics · 2013
This review presents an overview of the different techniques developed over the last decade to regulate the temperature within microfluidic systems. A variety of different approaches has been adopted, from external heating sources to Joule heating, microwaves or the use of lasers to cite just a few examples. The scope of the technical solutions developed to date is impressive and encompasses for instance temperature ramp rates ranging from 0.1 to 2,000 °C/s leading to homogeneous temperatures from −3 °C to 120 °C, and constant gradients from 6 to 40 °C/mm with a fair degree of accuracy. We also examine some recent strategies developed for applications such as digital microfluidics, where integration of a heating source to generate a temperature gradient offers control of a key parameter, without necessarily requiring great accuracy. Conversely, Temperature Gradient Focusing requires high accuracy in order to control both the concentration and separation of charged species. In addition, the Polymerase Chain Reaction requires both accuracy (homogeneous temperature) and integration to carry out demanding heating cycles. The spectrum of applications requiring temperature regulation is growing rapidly with increasingly important implications for the physical, chemical and biotechnological sectors, depending on the relevant heating technique.
Todd A. Duncombe, Augusto M. Tentori, Amy E. Herr
Nature Reviews Molecular Cell Biology · 2015
The underlying physical properties of microfluidic tools have led to new biological insights through the development of microsystems that can manipulate, mimic and measure biology at a resolution that has not been possible with macroscale tools. Microsystems readily handle sub-microlitre volumes, precisely route predictable laminar fluid flows and match both perturbations and measurements to the length scales and timescales of biological systems. The advent of fabrication techniques that do not require highly specialized engineering facilities is fuelling the broad dissemination of microfluidic systems and their adaptation to specific biological questions. We describe how our understanding of molecular and cell biology is being and will continue to be advanced by precision microfluidic approaches and posit that microfluidic tools - in conjunction with advanced imaging, bioinformatics and molecular biology approaches - will transform biology into a precision science.
Lingling Gong, Mehran Abbaszadeh Amirdehi, Amine Miled et al.
Sustainable Energy & Fuels · 2021
Oscillating ambient temperatures cause spikes in output voltage of soil microbial fuel cells, independent of temperature direction. The resulting output is higher than could be achieved at any constant temperature.
Siddharth Gadkari, Jean‐Marie Fontmorin, Eileen Hao Yu et al.
Chemical Engineering Journal · 2020
Paweł Sobieszuk, Anna Zamojska-Jaroszewicz, Łukasz Makowski
Journal of Power Sources · 2017
Marzieh Aghababaie, Mehrdad Farhadian, Azam Jeihanipour et al.
Environmental Technology Reviews · 2015
Kathryn Lawson, Ruggero Rossi, John M. Regan et al.
Bioresource Technology · 2020
Ferricyanide is often used in microbial fuel cells (MFCs) to avoid oxygen intrusion that occurs with air cathodes. However, MFC internal resistances using ferricyanide can be larger than those with air cathodes even though ferricyanide results in higher power densities. Using a graphite fiber brush cathode and a ferricyanide catholyte (FC-B) the internal resistance was 62 ± 4 mΩ m 2 , with 84 ± 8 mΩ m 2 obtained using ferricyanide and a flat carbon paper cathode (FC-F) and only 51 ± 1 mΩ m 2 using a 70% porosity air cathode (A-70). The FC-B MFCs produced the highest maximum power density of all configurations examined: 2.46 ± 0.26 W/m 2 , compared to 1.33 ± 0.14 W/m 2 for the A-70 MFCs. The electrode potential slope (EPS) analysis method showed that electrode resistances were similar for ferricyanide and air-cathode MFCs, and that higher power was due to the larger experimental working potential (500 ± 12 mV) of ferricyanide compared to the air cathode (233 ± 5 mV).
Huijie Hou, Lei Li, Paul de Figueiredo et al.
Biosensors and Bioelectronics · 2011
Microbial fuel cells (MFCs) have generated excitement in environmental and bioenergy communities due to their potential for coupling wastewater treatment with energy generation and powering diverse devices. The pursuit of strategies such as improving microbial cultivation practices and optimizing MFC devices has increased power generating capacities of MFCs. However, surprisingly few microbial species with electrochemical activity in MFCs have been identified because current devices do not support parallel analyses or high throughput screening. We have recently demonstrated the feasibility of using advanced microfabrication methods to fabricate an MFC microarray. Here, we extend these studies by demonstrating a microfabricated air-cathode MFC array system. The system contains 24 individual air-cathode MFCs integrated onto a single chip. The device enables the direct and parallel comparison of different microbes loaded onto the array. Environmental samples were used to validate the utility of the air-cathode MFC array system and two previously identified isolates, 7Ca (Shewanella sp.) and 3C (Arthrobacter sp.), were shown to display enhanced electrochemical activities of 2.69 mW/m(2) and 1.86 mW/m(2), respectively. Experiments using a large scale conventional air-cathode MFC validated these findings. The parallel air-cathode MFC array system demonstrated here is expected to promote and accelerate the discovery and characterization of electrochemically active microbes.
Zheng Ge, Jian Li, Xiao Li et al.
Environmental Science & Technology Letters · 2013
Perry L. McCarty, Jaeho Bae, Jeonghwan Kim
Environmental Science & Technology · 2011
In seeking greater sustainability in water resources management, wastewater is now being considered more as a resource than as a waste-a resource for water, for plant nutrients, and for energy. Energy, the primary focus of this article, can be obtained from wastewater's organic as well as from its thermal content. Also, using wastewater's nitrogen and P nutrients for plant fertilization, rather than wasting them, helps offset the high energy cost of producing synthetic fertilizers. Microbial fuel cells offer potential for direct biological conversion of wastewater's organic materials into electricity, although significant improvements are needed for this process to be competitive with anaerobic biological conversion of wastewater organics into biogas, a renewable fuel used in electricity generation. Newer membrane processes coupled with complete anaerobic treatment of wastewater offer the potential for wastewater treatment to become a net generator of energy, rather than the large energy consumer that it is today.
Zhen He
ACS Energy Letters · 2017
Hao Ren
Frontiers in Mechanical Engineering · 2021
Alireza Ahmadian Yazdi, Lorenzo D’Angelo, Nada Omer et al.
Biosensors and Bioelectronics · 2016
The use of carbon nanotubes (CNTs) for energy harvesting devices is preferable due to their unique mechanical, thermal, and electrical properties. On the other hand, microbial fuel cells (MFCs) are promising devices to recover carbon-neutral energy from the organic matters, and have been hindered with major setbacks towards commercialization. Nanoengineered CNT-based materials show remarkable electrochemical properties, and therefore have provided routes towards highly effective modification of MFC compartments to ultimately reach the theoretical limits of biomass energy recovery, low-cost power production, and thus the commercialization of MFCs. Moreover, these CNT-based composites offer significant flexibility in the design of MFCs that enable their use for a broad spectrum of applications ranging from scaled-up power generation to medically related devices. This article reviews the recent advances in the modification of MFCs using CNTs and CNT-based composites, and the extent to which each modification route impacts MFC power and current generation.
Laura Beuth, Catharina Philine Pfeiffer, Uwe Schröder
Energy & Environmental Science · 2020
Copper sulphides are shown to act as a conductive matrix improving the electrogenic performance of Geobacter dominated biofilms.
Xu Wang, Dengfeng Li, Xuhui Mao et al.
Journal of Power Sources · 2016
Mohammad Mahdi Mardanpour, Soheila Yaghmaei
Biosensors and Bioelectronics · 2016
This study reports the fabrication of a microfluidic microbial fuel cell (MFC) using nickel as a novel alternative for conventional electrodes and a non-phatogenic strain of Escherichia coli as the biocatalyst. The feasibility of a microfluidic MFC as an efficient power generator for production of bioelectricity from glucose and urea as organic substrates in human blood and urine for implantable medical devices (IMDs) was investigated. A maximum open circuit potential of 459 mV was achieved for the batch-fed microfluidic MFC. During continuous mode operation, a maximum power density of 104 Wm(-3) was obtained with nutrient broth. For the glucose-fed microfluidic MFC, the maximum power density of 5.2 μW cm(-2) obtained in this study is significantly greater than the power densities reported previously for microsized MFCs and glucose fuel cells. The maximum power density of 14 Wm(-3) obtained using urea indicates the successful performance of a microfluidic MFC using human excreta. It features high power density, self-regeneration, waste management and a low production cost (<$1), which suggest it as a promising alternative to conventional power supplies for IMDs. The performance of the microfluidic MFC as a power supply was characterized based on polarization behavior and cell potential in different substrates, operational modes, and concentrations.
Siti Aishah Muhmed, Nor Azureen Mohamad Nor, Juhana Jaafar et al.
Energy, Ecology and Environment · 2019
Zhigao Wang, Yidan Hu, Yiran Dong et al.
Microbial Biotechnology · 2022
Abstract Protein nanowires are critical electroactive components for electron transfer of Geobacter sulfurreducens biofilm. To determine the applicability of the nanowire proteins in improving bioelectricity production, their genes including pilA , omcZ , omcS and omcT were overexpressed in G. sulfurreducens . The voltage outputs of the constructed strains were higher than that of the control strain with the empty vector (0.470–0.578 vs. 0.355 V) in microbial fuel cells (MFCs). As a result, the power density of the constructed strains (i.e. 1.39–1.58 W m −2 ) also increased by 2.62‐ to 2.97‐fold as compared to that of the control strain. Overexpression of nanowire proteins also improved biofilm formation on electrodes with increased protein amount and thickness of biofilms. The normalized power outputs of the constructed strains were 0.18–0.20 W g −1 that increased by 74% to 93% from that of the control strain. Bioelectrochemical analyses further revealed that the biofilms and MFCs with the constructed strains had stronger electroactivity and smaller internal resistance, respectively. Collectively, these results demonstrate for the first time that overexpression of nanowire proteins increases the biomass and electroactivity of anode‐attached microbial biofilms. Moreover, this study provides a new way for enhancing the electrical outputs of MFCs.
Hao Ren, He Tian, Cameron L. Gardner et al.
Nanoscale · 2016
We report a miniaturized microbial fuel cell, integrated with a 3D free-standing graphene scaffold, delivering a record high power density of 11 220 W m −3 .
Qi Wang, Shuren Song, Wei Wang et al.
Journal of The Electrochemical Society · 2022
While gold is a stable metal in water, it is not uncommon for microfluidic experimenters using biologically-relevant fluids such as phosphate-buffered saline (PBS) to witness their precious gold electrodes quickly vanish from the microchannel once the voltage exceeds a few volts. This stability issue concerns multiple fields where high voltage provides superior actuator or sensor performance, such as resistive pulse sensing (RPS), electroosmosis, electrowetting and so on. One solution to protect metallic electrodes is using alternative voltages (AV) as opposed to continuous voltages. After recalling that gold dissolution is enabled by the chloride ions present in most biologically-relevant solutions, we explore the stability conditions of the electrodes for voltages from 1 to 20 V pp (Peak to Peak voltage amplitude), actuation frequencies between 0 and 5 kHz, and for various pH and electrolytes (NaCl, Na 2 SO 4 , HCl). We find that the dissolution threshold voltage depends on the ratio of reaction to diffusion rate given by the Damkhöler number Da. In mass-transfer limited regime, the dissolution threshold is independent of the frequency, whereas the dissolution voltage is observed to grow as Da −1/2 in the reaction limited regime. These findings provide guidelines to design more reliable electrowetting, electroosmosis, dielectrophoresis and resistive pulse sensing devices.
Mohammad Asaduzzaman Chowdhury, Nayem Hossain, Syed Rokibul Islam et al.
Energy Reports · 2023
Farnaz Asayesh, Mir Pouyan Zarabadi, Nahid Babaei Aznaveh et al.
Analytical Methods · 2018
Introduction of bacterial inoculant into a chemostat bioreactor can lead to unwanted contamination of upstream elements via chemotaxis. Passive microfluidic elements show the potential to solve this problem.
Lu Yuan, Hervé Straub, Liubov Shishaeva et al.
Annual Review of Analytical Chemistry · 2023
Biofilms are multicellular communities held together by a self-produced extracellular matrix and exhibit a set of properties that distinguish them from free-living bacteria. Biofilms are exposed to a variety of mechanical and chemical cues resulting from fluid motion and mass transport. Microfluidics provides the precise control of hydrodynamic and physicochemical microenvironments to study biofilms in general. In this review, we summarize the recent progress made in microfluidics-based biofilm research, including understanding the mechanism of bacterial adhesion and biofilm development, assessment of antifouling and antimicrobial properties, development of advanced in vitro infection models, and advancement in methods to characterize biofilms. Finally, we provide a perspective on the future direction of microfluidics-assisted biofilm research.
Dingding Ye, Pengqing Zhang, Jun Li et al.
International Journal of Hydrogen Energy · 2021
Ahmed ElMekawy, Hanaa M. Hegab, Xochitl Dominguez‐Benetton et al.
Bioresource Technology · 2013
The efficiency of microbial fuel cells (MFCs) is affected by several factors such as activation overpotentials, ohmic losses and concentration polarization. These factors are handled in micro-sized MFCs using special electrodes with physically or chemically modified surfaces constructed with specified materials. Most of the existing μLscale MFCs show great potential in rapid screening of electrochemically-active microbes and electrode performance; although they generate significantly lower volumetric power density compared with their mL counterparts because of their high internal resistance. This review presents the development of microfluidic MFCs, with summarization of their advantages and challenges, and focuses on the efforts done to minimize the adverse effects of internal resistance (ohmic and non-ohmic) on their performance.
Hongchul Jang, Roberto Rusconi, Roman Stocker
npj Biofilms and Microbiomes · 2017
Abstract Bacteria often adhere to surfaces, where they form communities known as biofilms. Recently, it has been shown that biofilm formation initiates with the microscopically heterogeneous deposition of a skeleton of extracellular polymeric substances (EPS) by individual cells crawling on the surface, followed by growth of the biofilm into a surface-covering continuum. Here we report microfluidic experiments with Pseudomonas aeruginosa biofilms showing that their “hidden” heterogeneity can affect the later dynamics of their disruption. Using controlled air bubbles as a model for mechanical insult, we demonstrate that biofilm disruption is strongly dependent on biofilm age, and that disruption to early-stage biofilms can take the shape of a semi-regular pattern of ~15 µm diameter holes from which bacteria have been removed. We explain hole formation in terms of the rupture and retreat of the thin liquid layer created by the long bubble, which scrapes bacteria off the surface and rearranges their distribution. We find that the resulting pattern correlates with the spatial distribution of EPS: holes form where there is less EPS, whereas regions with more EPS act as strongholds against the scraping liquid front. These results show that heterogeneity in the microscale EPS skeleton of biofilms has profound consequences for later dynamics, including disruption. Because few attached cells suffice to regrow a biofilm, these results point to the importance of considering microscale heterogeneity when designing and assessing the effectiveness of biofilm removal strategies by mechanical forces.
Mingpeng Yang, Nan Sun, Yong Luo et al.
Biomicrofluidics · 2022
Bubbles in microfluidics—even those that appear to be negligibly small—are pervasive and responsible for the failure of many biological and chemical experiments. For instance, they block current conduction, damage cell membranes, and interfere with detection results. To overcome this unavoidable and intractable problem, researchers have developed various methods for capturing and removing bubbles from microfluidics. Such methods are multifarious and their working principles are very different from each other. In this review, bubble-removing methods are divided into two broad categories: active debubblers (that require external auxiliary equipment) and passive debubblers (driven by natural processes). In each category, three main types of methods are discussed along with their advantages and disadvantages. Among the active debubblers, those assisted by lasers, acoustic generators, and negative pressure pumps are discussed. Among the passive debubblers, those driven by buoyancy, the characteristics of gas–liquid interfaces, and the hydrophilic and hydrophobic properties of materials are discussed. Finally, the challenges and prospects of the bubble-removal technologies are reviewed to refer researchers to microfluidics and inspire further investigations in this field.
Farnaz Asayesh, Mir Pouyan Zarabadi, Jesse Greener
Biomicrofluidics · 2017
Specially designed microfluidic bioflow cells were used to temporarily trap microbubbles during different inoculation stages of Pseudomonas sp. biofilms. Despite being eliminated many hours before biofilm appearance, templated growth could occur at former bubble positions. Bubble-templated growth was either continuous or in ring patterns, depending on the stage of inoculation when the bubbles were introduced. Templated biofilms were strongly enhanced in terms of their growth kinetics and structural homogeneity. High resolution confocal imaging showed two separate bubble-induced bacterial trapping modes, which were responsible for the altered biofilm development. It is concluded that static bubbles can be exploited for fundamental improvements to bioreactor performance, as well as open new avenues to study isolated bacteria and small colonies.
Mohammad Pousti, Maxime Joly, Patrice Roberge et al.
Analytical Chemistry · 2018
Jonathan Winfield, Ioannis Ieropoulos, John Greenman et al.
Bioelectrochemistry · 2011
Axel Günther, Klavs F. Jensen
Lab Chip · 2006
We review transport characteristics of pressure-driven, multiphase flows through microchannel networks tens of nanometres to several hundred of micrometres wide with emphasis on conditions resulting in enhanced mixing and reduced axial dispersion. Dimensionless scaling parameters useful in characterizing multiphase flows are summarized along with experimental flow visualization techniques. Static and dynamic stability considerations are also included along with methods for stabilizing multiphase flows through surface modifications. Observed gas-liquid and immiscible liquid-liquid flows are summarized in terms of flow regime diagrams and the different flows are related to applications in chemistry and materials synthesis. Means to completely separate multiphase flows on the microscale and guidelines for design of scalable multiphase systems are also discussed.