| 1. |
- Ackermann, Yvonne, et al.
(författare)
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Design of a bioelectrocatalytic electrode interface for oxygen reduction in biofuel cells based on a specifically adapted Os-complex containing redox polymer with entrapped Trametes hirsuta laccase
- 2010
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Ingår i: Electrochemistry communications. - : Elsevier. - 1388-2481 .- 1873-1902. ; 12:5, s. 640-643
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Tidskriftsartikel (refereegranskat)abstract
- The design of the coordination shell of an Os-complex and its integration within an electrodeposition polymer enables fast electron transfer between an electrode and a polymer entrapped high-potential laccase from the basidiomycete Trametes hirsuta. The redox potential of the Os3+/2+-centre tethered to the polymer backbone (+720 mV vs. NHE) is perfectly matching the potential of the enzyme (+780 mV vs. NHE at pH 6.5). The laccase and the Os-complex modified anodic electrodeposition polymer were simultaneously precipitated on the surface of a glassy carbon electrode by means of a pH-shift to 2.5. The modified electrode was investigated with respect to biocatalytic oxygen reduction to water. The proposed modified electrode has potential applications as biofuel cell cathode.
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| 2. |
- Alsaoub, Sabine, et al.
(författare)
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An Intrinsic Self-Charging Biosupercapacitor Comprised of a High-Potential Bioanode and a Low-Potential Biocathode
- 2017
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Ingår i: ChemPlusChem. - : John Wiley & Sons. - 2192-6506. ; 82:4, s. 576-583
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Tidskriftsartikel (refereegranskat)abstract
- An intrinsic self-charging biosupercapacitor built on a unique concept for the fabrication of biodevices based on redox polymers is presented. The biosupercapacitor consists of a high-potential redox polymer based bioanode and a low-potential redox polymer based biocathode in which the potentials of the electrodes in the discharged state show an apparent potential mismatch E-anode > E-cathode and prevent the use of the device as a conventional biofuel cell. Upon charging, the potentials of the electrodes are shifted to more positive (cathode) and more negative (anode) values because of a change in the a(ox-)to-a(red) ratio within the redox polymer matrix. Hence, a potential inversion occurs in the charged state (E-anode < E-cathode) and an open circuit voltage of >0.4 V is achieved and the bio-device acts as a true biosupercapacitor. The bioanode consists of a novel specifically designed high-potential Os complex modified polymer for the efficient immobilization and electrical wiring of glucose converting enzymes, such as glucose oxidase and flavin adenine dinucleotide (FAD)-dependent glucose dehydrogenase. The cathodic side is constructed from a low-potential Os complex modified polymer integrating the O-2 reducing enzyme, bilirubin oxidase. The large potential differences between the redox polymers and the prosthetic groups of the biocatalysts ensure fast and efficient charging of the biodevice.
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| 3. |
- Beck, Wolfgang, et al.
(författare)
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Die ältesten Runeninschriften im Kontext (sprach)wissenschaftlicher Editionen
- 2015
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Ingår i: Futhark. - 1892-0950 .- 1892-0950. ; 5, s. 7-24
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Tidskriftsartikel (refereegranskat)abstract
- Comprehensive editions of the oldest runic inscriptions are few and largely outdated;even the more recent ones do not meet modern critical standards. Other runic publications that treat this material tend to concentrate on selected data only. An up-to-date scholarly edition of the oldest runic inscriptions is thus currently lacking. The question is: what criteria must a new edition fulfil? Of course, information has to be provided concerning the rune-bearing object, such as (1) a description of the artifact, including the present place of keeping, (2) the find circumstances and (3) an archaeological dating. The description of the inscription itself has to be thorough, and must include (1) a plausible reading of the runes with remarks on runic forms and the textual composition, and (2) a transliteration, which constitutes the basis for a transcription. The transcription is the starting point for the internal, viz. linguistic interpretation that has to contain etymological as well as syntactic information (where necessary). In the etymological component, all important proposals have to be reconsidered. The linguistic interpretation must be the starting point for any broader analyses, which of necessity will require an interdisciplinary approach. The paper shows how such an edition can be laid out by means of one selected example.
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| 4. |
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| 5. |
- Bobrowski, Tim, et al.
(författare)
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Rechargeable, flexible and mediator-free biosupercapacitor based on transparent ITO nanoparticle modified electrodes acting in mu M glucose containing buffers
- 2018
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Ingår i: Biosensors & bioelectronics. - : Elsevier. - 0956-5663 .- 1873-4235. ; 101, s. 84-89
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Tidskriftsartikel (refereegranskat)abstract
- We present a transparent and flexible self-charging biosupercapacitor based on an optimised mediator- and membrane-free enzymatic glucose/oxygen biofuel cell. Indium tin oxide (ITO) nanoparticles were spray-coated on transparent conducting ITO supports resulting in a flocculent, porous and nanostructured electrode surface. By this, high capacitive currents caused by an increased electrochemical double layer as well as enhanced catalytic currents due to a higher number of immobilised enzyme molecules were obtained. After a chemical pretreatment with a silane derivative, bilirubin oxidase from Myrothecium verrucaria was immobilized onto the ITO nanostructured electrode surface under formation of a biocathode, while bioanodes were obtained by either immobilisation of cellobiose dehydrogenase from Corynascus thermophilus or soluble PQQ-dependent glucose dehydrogenase from Acinetobacter calcoaceticus. The latter showed a lower apparent K-M value for glucose conversion and higher catalytic currents at mu M glucose concentrations. Applying the optimised device as a biosupercapacitor in a discontinuous charge/discharge mode led to a generated power output of 0.030 mW/cm(2) at 50 mu M glucose, simulating the glucose concentration in human tears. This represents an enhancement by a factor of 350 compared to the power density obtained from the continuously operating biofuel cell with a maximum power output of 0.086 mu W/cm(2) under the same conditions. After 17 h of charging/discharging cycles a remarkable current enhancement was still measured. The entire device was transferred to flexible materials and applied for powering a flexible display showing its potential applicability as an intermittent power source in smart contact lenses.
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| 6. |
- Falk, Magnus, et al.
(författare)
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Self-powered wireless carbohydrate/oxygen sensitive biodevice based on radio signal transmission
- 2014
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Ingår i: PLOS ONE. - : Public Library of Science. - 1932-6203. ; 9:10, s. e109104/1-e109104/9
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Tidskriftsartikel (refereegranskat)abstract
- Here for the first time, we detail self-contained (wireless and self-powered) biodevices with wireless signal transmission. Specifically, we demonstrate the operation of self-sustained carbohydrate and oxygen sensitive biodevices, consisting of a wireless electronic unit, radio transmitter and sep. sensing bioelectrodes, supplied with elec. energy from a combined multi-enzyme fuel cell generating sufficient current at required voltage to power the electronics. A carbohydrate/oxygen enzymic fuel cell was assembled by comparing the performance of a range of different bioelectrodes followed by selection of the most suitable, stable combination. Carbohydrates (viz. lactose for the demonstration) and oxygen were also chosen as bioanalytes, being important biomarkers, to demonstrate the operation of the self-contained biosensing device, employing enzyme-modified bioelectrodes to enable the actual sensing. A wireless electronic unit, consisting of a micropotentiostat, an energy harvesting module (voltage amplifier together with a capacitor) and a radio microchip, were designed to enable the biofuel cell to be used as a power supply for managing the sensing devices and for wireless data transmission. The electronic system used required current and voltages greater than 44 μA and 0.57 V, resp. to operate; which the biofuel cell was capable of providing, when placed in a carbohydrate and oxygen contg. buffer. In addn., a USB based receiver and computer software were employed for proof-of concept tests of the developed biodevices. Operation of bench-top prototypes was demonstrated in buffers contg. different concns. of the analytes, showcasing that the variation in response of both carbohydrate and oxygen biosensors could be monitored wirelessly in real-time as analyte concns. in buffers were changed, using only an enzymic fuel cell as a power supply.
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| 7. |
- Figueiredo, Carina, et al.
(författare)
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Effect of Protection Polymer Coatings on the Performance of an Amperometric Galactose Biosensor in Human Plasma
- 2024
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Ingår i: Biosensors. - 2079-6374. ; 14:4
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Tidskriftsartikel (refereegranskat)abstract
- Galactose monitoring in individuals allows the prevention of harsh health conditions related to hereditary metabolic diseases like galactosemia. Current methods of galactose detection need development to obtain cheaper, more reliable, and more specific sensors. Enzyme-containing amperometric sensors based on galactose oxidase activity are a promising approach, which can be enhanced by means of their inclusion in a redox polymer coating. This strategy simultaneously allows the immobilization of the biocatalyst to the electroactive surface and hosts the electron shuttling units. An additional deposition of capping polymers prevents external interferences like ascorbic or uric acid as well as biofouling when measuring in physiological fuels. This work studies the protection effect of poly(2-methacryloyloxyethyl phosphorylcholine-co-glycidyl methacrylate (MPC) and polyvinylimidazole-polysulfostyrene (P(VI-SS)) when incorporated in the biosensor design for the detection of galactose in human plasma.
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| 8. |
- Glithero, Nick, et al.
(författare)
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At-line measurement of lactose in dairy-processing plants
- 2013
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Ingår i: Analytical and Bioanalytical Chemistry. - : Springer Science and Business Media LLC. - 1618-2642 .- 1618-2650. ; 405:11, s. 3791-3799
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Tidskriftsartikel (refereegranskat)abstract
- Environmental and process control applications have needs for sensors that operate continuously or repeatedly, making them applicable to batch measurement and flowing product stream measurement. Additionally, for lactose monitoring in dairy-processing plants, the sensors must have sufficient flexibility to handle a wide range of substrate concentration and be resilient to withstand wide pH excursions brought about by frequent exposure to clean-in-place chemicals that happen without any warning. This paper describes the development and trialling of an at-line lactose biosensor that meets the needs of the dairy industry for loss monitoring of lactose in dairy-processing plants by the combination of a third-generation enzyme biosensor with a sequential injection analyser. Results, both from grab sample analysis and an at-line factory prototype, are shown from their operation when installed at a Fonterra dairy factory (New Zealand) during the 2011-2012 season. Previous sensor fabrication methods were converted to a single-step process, and the flow-through cell was adapted to bubble-free operation. The lactose concentration in wastewater-processing streams was successfully monitored by taking and analysing samples every 2-3 min, semi-continuously, for 3 months by an unskilled operator. The Fonterra site flushes approximately 100-300,000 L of wastewater per hour from its lactose plant. In the 2011-2012 season, the daily mean lactose content of this wastewater varied significantly, from 0.0 to 8.0 % w/v (0-233,712 mu M) and equated to substantial total losses of lactose over a 6-month period. These lactose losses represent lost saleable or useable product.
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| 9. |
- Gonzalez-Arribas, Elena, et al.
(författare)
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Solar biosupercapacitor
- 2017
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Ingår i: Electrochemistry Communications. - : Elsevier BV. - 1388-2481 .- 1873-1902. ; 74, s. 9-13
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Tidskriftsartikel (refereegranskat)abstract
- Here we report on an entirely new kind of bioelectronic device – a solar biosupercapacitor, which is built from a dual-feature photobioanode combined with a double-function enzymatic cathode. The self-charging biodevice, based on transparent nanostructured indium tin oxide electrodes modified with biological catalysts, i.e. thylakoid membranes and bilirubin oxidase, is able to capacitively store electricity produced by direct conversion of radiant energy into electric energy. When self-charged during 10 min, using ambient light only, the biosupercapacitor provided a maximum of 6 mW m− 2 at 0.20 V.
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| 10. |
- Gonzalez-Arribas, Elena, et al.
(författare)
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Transparent, mediator- and membrane-free enzymatic fuel cell based on nanostructured chemically modified indium tin oxide electrodes
- 2017
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Ingår i: Biosensors & bioelectronics. - : Elsevier. - 0956-5663 .- 1873-4235. ; 97, s. 46-52
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Tidskriftsartikel (refereegranskat)abstract
- We detail a mediator- and membrane-free enzymatic glucose/oxygen biofuel cell based on transparent and nanostructured conducting supports. Chemically modified indium tin oxide nanoparticle modified electrodes were used to substantially increase the active surface area without significantly compromising transparency. Two different procedures for surface nanostructuring were employed, viz. spray-coating and drop-coating. The spray-coated biodevice showed superior characteristics as compared to the drop-coated enzymatic fuel cell, as a result of the higher nanostructured surface area as confirmed by electrochemical characterisation, as well as scanning electron and atomic force microscopy. Subsequent chemical modification with silanes, followed by the immobilisation of either cellobiose dehydrogenase from Corynascus thermophiles or bilirubin oxidase from Myrothecium verrucaria, were performed to obtain the bioanodes and biocathodes, respectively. The optimised biodevice exhibited an OCV of 0.67 V and power output of up to 1.4 mu W/cm(2) at an operating voltage of 0.35 V. This is considered a significant step forward in the field of glucose/oxygen membrane- and mediator-free, transparent enzymatic fuel cells.
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