Evaluation of a Yeast–Polypyrrole Biocomposite Used in Microbial Fuel Cells

Electrically conductive polymers are promising materials for charge transfer from living cells to the anodes of electrochemical biosensors and biofuel cells. The modification of living cells by polypyrrole (PPy) causes shortened cell lifespan, burdens the replication process, and diminishes renewability in the long term. In this paper, the viability and morphology non-modified, inactivated, and PPy-modified yeasts were evaluated. The results displayed a reduction in cell size, an incremental increase in roughness parameters, and the formation of small structural clusters of polymers on the yeast cells with the increase in the pyrrole concentration used for modification. Yeast modified with the lowest pyrrole concentration showed minimal change; thus, a microbial fuel cell (MFC) was designed using yeast modified by a solution containing 0.05 M pyrrole and compared with the characteristics of an MFC based on non-modified yeast. The maximal generated power of the modified system was 47.12 mW/m2, which is 8.32 mW/m2 higher than that of the system based on non-modified yeast. The open-circuit potentials of the non-modified and PPy-modified yeast-based cells were 335 mV and 390 mV, respectively. Even though applying a PPy layer to yeast increases the charge-transfer efficiency towards the electrode, the damage done to the cells due to modification with a higher concentration of PPy diminishes the amount of charge transferred, as the current density drops by 846 μA/cm2. This decrease suggests that modification by PPy may have a cytotoxic effect that greatly hinders the metabolic activity of yeast.

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From Microorganism-Based Amperometric Biosensors Towards Microbial Fuel Cells

Sensors ◽

10.3390/s21072442 ◽

2021 ◽

Vol 21 (7) ◽

pp. 2442

Author(s):

Eivydas Andriukonis ◽

Raimonda Celiesiute-Germaniene ◽

Simonas Ramanavicius ◽

Roman Viter ◽

Arunas Ramanavicius

Keyword(s):

Charge Transfer ◽

Conducting Polymers ◽

Microbial Fuel Cells ◽

Biofuel Cells ◽

Biofuel Cell ◽

Transfer Efficiency ◽

Amperometric Biosensors ◽

Immobilization Of Enzymes ◽

Critical Issues ◽

Microbial Biofuel

This review focuses on the overview of microbial amperometric biosensors and microbial biofuel cells (MFC) and shows how very similar principles are applied for the design of both types of these bioelectronics-based devices. Most microorganism-based amperometric biosensors show poor specificity, but this drawback can be exploited in the design of microbial biofuel cells because this enables them to consume wider range of chemical fuels. The efficiency of the charge transfer is among the most challenging and critical issues during the development of any kind of biofuel cell. In most cases, particular redox mediators and nanomaterials are applied for the facilitation of charge transfer from applied biomaterials towards biofuel cell electrodes. Some improvements in charge transfer efficiency can be achieved by the application of conducting polymers (CPs), which can be used for the immobilization of enzymes and in some particular cases even for the facilitation of charge transfer. In this review, charge transfer pathways and mechanisms, which are suitable for the design of biosensors and in biofuel cells, are discussed. Modification methods of the cell-wall/membrane by conducting polymers in order to enhance charge transfer efficiency of microorganisms, which can be potentially applied in the design of microbial biofuel cells, are outlined. The biocompatibility-related aspects of conducting polymers with microorganisms are summarized.

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Baker’s Yeast-Based Microbial Fuel Cell Mediated by 2-Methyl-1,4-Naphthoquinone

Membranes ◽

10.3390/membranes11030182 ◽

2021 ◽

Vol 11 (3) ◽

pp. 182

Author(s):

Juste Rozene ◽

Inga Morkvenaite-Vilkonciene ◽

Ingrida Bruzaite ◽

Antanas Zinovicius ◽

Arunas Ramanavicius

Keyword(s):

Fuel Cells ◽

Fuel Cell ◽

Microbial Fuel Cell ◽

Microbial Fuel Cells ◽

Solution Concentration ◽

Open Circuit ◽

Baker’S Yeast ◽

Yeast Cells ◽

Baker's Yeast ◽

Yeast Viability

Microbial fuel cell (MFC) efficiency depends on charge transfer capability from microbe to anode, and the application of suitable redox mediators is important in this area. In this study, yeast viability experiments were performed to determine the 2-methyl-1,4-naphthoquinone (menadione (MD)) influence on different yeast cell species (baker’s yeast and Saccharomyces cerevisiae yeast cells). In addition, electrochemical measurements to investigate MFC performance and efficiency were carried out. This research revealed that baker’s yeast cells were more resistant to dissolved MD, but the current density decreased when yeast solution concentration was incrementally increased in the same cell. The maximal calculated power of a designed baker’s yeast-based MFC cell anode was 0.408 mW/m2 and this power output was registered at 24 mV. Simultaneously, the cell generated a 62-mV open circuit potential in the presence of 23 mM potassium ferricyanide and the absence of glucose and immobilized MD. The results only confirm that MD has strong potential to be applied to microbial fuel cells and that a two-redox-mediator-based system is suitable for application in microbial fuel cells.

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A Microfluidic-Enabled Mechanical Microcompressor for the Immobilization of Live Single- and Multi-Cellular Specimens

Microscopy and Microanalysis ◽

10.1017/s1431927613014037 ◽

2014 ◽

Vol 20 (1) ◽

pp. 141-151 ◽

Cited By ~ 14

Author(s):

Yingjun Yan ◽

Liwei Jiang ◽

Karl J. Aufderheide ◽

Gus A. Wright ◽

Alexander Terekhov ◽

...

Keyword(s):

Drosophila Melanogaster ◽

Caenorhabditis Elegans ◽

Tetrahymena Thermophila ◽

Living Cells ◽

Yeast Cells ◽

Cellular Structures ◽

Mechanical Device ◽

Cellular Events ◽

Protozoan Species

AbstractA microcompressor is a precision mechanical device that flattens and immobilizes living cells and small organisms for optical microscopy, allowing enhanced visualization of sub-cellular structures and organelles. We have developed an easily fabricated device, which can be equipped with microfluidics, permitting the addition of media or chemicals during observation. This device can be used on both upright and inverted microscopes. The apparatus permits micrometer precision flattening for nondestructive immobilization of specimens as small as a bacterium, while also accommodating larger specimens, such as Caenorhabditis elegans, for long-term observations. The compressor mount is removable and allows easy specimen addition and recovery for later observation. Several customized specimen beds can be incorporated into the base. To demonstrate the capabilities of the device, we have imaged numerous cellular events in several protozoan species, in yeast cells, and in Drosophila melanogaster embryos. We have been able to document previously unreported events, and also perform photobleaching experiments, in conjugating Tetrahymena thermophila.

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Use of Transparent Conductive Oxide Materials with Low Indices of Refraction in Amorphous Silicon-Based Solar Cell Technology

MRS Proceedings ◽

10.1557/proc-862-a21.1 ◽

2005 ◽

Vol 862 ◽

Author(s):

Scott J. Jones ◽

Joachim Doehler ◽

Tongyu Liu ◽

David Tsu ◽

Jeff Steele ◽

...

Keyword(s):

Solar Cell ◽

Amorphous Silicon ◽

Transparent Conductive Oxide ◽

Open Circuit ◽

Long Term Stability ◽

Back Reflectors ◽

Stability Issues ◽

Silicon Based ◽

Solar Cell Technology

AbstractNew types of transparent conductive oxides with low indices of refraction have been developed for use in optical stacks for the amorphous silicon (a-Si) solar cell and other thin film applications. The alloys are ZnO based with Si and MgF added to reduce the index of the materials through the creation of SiO2 or MgF2, with n=1.3-1.4, or the addition of voids in the materials. Alloys with 12-14% Si or Mg have indices of refraction at λ=800nm between 1.6 and 1.7. These materials are presently being used in optical stacks to enhance light scattering by Al/multi-layer/ZnO back reflectors in a-Si based solar cells to increase light absorption in the semiconductor layers and increase open circuit currents and boost device efficiencies. In contrast to Ag/ZnO back reflectors which have long term stability issues due to electromigration of Ag, these Al based back reflectors should be stable and usable in manufactured PV products. In this manuscript, structural properties for the materials will be reported as well as the performance of solar cell devices made using these new types of materials.

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Turnover of lake sediments treated with sediment microbial fuel cells: a long-term study in a eutrophic lake

The Science of The Total Environment ◽

10.1016/j.scitotenv.2021.148880 ◽

2021 ◽

pp. 148880

Author(s):

Xinyu Lu ◽

Karl August von Haxthausen ◽

Andreas Libonati Brock ◽

Stefan Trapp

Keyword(s):

Fuel Cells ◽

Lake Sediments ◽

Microbial Fuel Cells ◽

Eutrophic Lake ◽

Term Study ◽

Long Term Study

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Impact of external resistance acclimation on charge transfer and diffusion resistance in bench-scale microbial fuel cells

Bioresource Technology ◽

10.1016/j.biortech.2020.123921 ◽

2020 ◽

Vol 318 ◽

pp. 123921 ◽

Cited By ~ 2

Author(s):

Ruggero Rossi ◽

Bruce E. Logan

Keyword(s):

Fuel Cells ◽

Charge Transfer ◽

Microbial Fuel Cells ◽

Diffusion Resistance ◽

External Resistance ◽

Bench Scale ◽

And Diffusion

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A fluorogenic and chromogenic dual sensor for the detection of cyanide and copper(ii) in water samples and living cells

Analytical Methods ◽

10.1039/c6ay01902a ◽

2016 ◽

Vol 8 (38) ◽

pp. 6909-6915 ◽

Cited By ~ 7

Author(s):

T. M. Ebaston ◽

G. Balamurugan ◽

S. Velmathi

Keyword(s):

Charge Transfer ◽

Detection Limit ◽

Fluorescent Sensor ◽

Aqueous Media ◽

Living Cells ◽

Dual Sensor ◽

Molecular Charge ◽

Intra Molecular Charge Transfer ◽

Good Detection Limit ◽

Good Detection

Here we describe a simple fluorescent sensor based on intra molecular charge transfer to detect cyanide in aqueous media selectively with a very good detection limit and cascade recognition of aq. copper(ii) ions.

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Automatic synchronisation of the cell cycle in budding yeast through closed-loop feedback control

Nature Communications ◽

10.1038/s41467-021-22689-w ◽

2021 ◽

Vol 12 (1) ◽

Author(s):

Giansimone Perrino ◽

Sara Napolitano ◽

Francesca Galdi ◽

Antonella La Regina ◽

Davide Fiore ◽

...

Keyword(s):

Cell Cycle ◽

Autonomous Vehicles ◽

Genetic System ◽

Yeast Cells ◽

Control Engineering ◽

Loop Feedback ◽

Experimental Approaches ◽

Closed Loop Feedback ◽

Theoretical Foundations

AbstractThe cell cycle is the process by which eukaryotic cells replicate. Yeast cells cycle asynchronously with each cell in the population budding at a different time. Although there are several experimental approaches to synchronise cells, these usually work only in the short-term. Here, we build a cyber-genetic system to achieve long-term synchronisation of the cell population, by interfacing genetically modified yeast cells with a computer by means of microfluidics to dynamically change medium, and a microscope to estimate cell cycle phases of individual cells. The computer implements a controller algorithm to decide when, and for how long, to change the growth medium to synchronise the cell-cycle across the population. Our work builds upon solid theoretical foundations provided by Control Engineering. In addition to providing an avenue for yeast cell cycle synchronisation, our work shows that control engineering can be used to automatically steer complex biological processes towards desired behaviours similarly to what is currently done with robots and autonomous vehicles.

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SIMILARITY OF THE KINETICS OF INVERTASE ACTION IN VIVO AND IN VITRO. II

The Journal of General Physiology ◽

10.1085/jgp.16.2.233 ◽

1932 ◽

Vol 16 (2) ◽

pp. 233-242 ◽

Cited By ~ 27

Author(s):

B. G. Wilkes ◽

Elizabeth T. Palmer

Keyword(s):

Physiological Activity ◽

Outer Region ◽

Living Cells ◽

Yeast Cells ◽

Live Cells ◽

Intracellular Enzyme ◽

Relationship Of ◽

Kinetics Of

1. The pH-activity relationship of invertase has been studied in vivo and in vitro under identical external environmental conditions. 2. The effect of changing (H+) upon the sucroclastic activity of living cells of S. cerevisiae and of invertase solutions obtained therefrom has been found, within experimental error, to be identical. 3. The region of living yeast cells in which invertase exerts its physiological activity changes its pH freely and to the same extent as that of the suspending medium. It is suggested that this may indicate that this intracellular enzyme may perform its work somewhere in the outer region of the cell. 4. In using live cells containing maltase, no evidence of increased sucroclastic activity around pH 6.9, due to the action of Weidenhagen's α-glucosidase (maltase), was found.

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