Evaluation of the degradation of acetaminophen by the filamentous fungus Scedosporium dehoogii using carbon-based modified electrodes

Different carbon-based materials have been compared for the development of NADH sensors: glassy carbon electrodes (GCE), multiwalled carbon nanotubes (MWCNT), and carbon black (CB). The GCE and MWCNT has been subjected to oxidative pretreatment to study the influence of oxidative groups for NADH oxidation. The materials had been characterized by FT-IR to identify the surface composition. The response of bare (GC) and GC/modified electrodes toward potassium ferricyanide have been employed to obtain information about the electroactive area and electron transfer rate. Studies of NAD+/NADH redox behavior showed that MWCNT and GCE exhibit high degree of passivation while CB shows no fouling effects. Catalytic effect of surface-oxygenated groups was also proved for GCE and MWCNT, and both, O-GCE and O-MWCNT, exhibited a lower oxidation overpotential compared to the respective untreated materials. Chronoamperometric quantification showed a linear dependence between 2–18 μmol·L−1 and a detection limits of 6.2 μmol·L−1 (GCE), 5.4 μmol·L−1 (O-GCE), 3.2 μmol·L−1 (GCE/CB), 9.6 μmol·L−1 (GCE/MWCNT), and 4.9 μmol·L−1 (GCE/O-MWCNT) were obtained. The analytical performances suggest that a careful choice of the material for NADH sensing is necessary depending on the sensor application.

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2D nanosheet molybdenum disulphide (MoS2) modified electrodes explored towards the hydrogen evolution reaction

Nanoscale ◽

10.1039/c5nr05164a ◽

2015 ◽

Vol 7 (43) ◽

pp. 18152-18168 ◽

Cited By ~ 77

Author(s):

Samuel J. Rowley-Neale ◽

Dale A. C. Brownson ◽

Graham C. Smith ◽

David A. G. Sawtell ◽

Peter J. Kelly ◽

...

Keyword(s):

Hydrogen Evolution ◽

Hydrogen Evolution Reaction ◽

Modified Electrodes ◽

Molybdenum Disulphide ◽

Carbon Based

2D molybdenum disulphide nanosheets are explored as an electrocatalyst towards the hydrogen evolution reaction (HER) using modified carbon based electrodes.

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An overview of the electrochemical reduction of oxygen at carbon-based modified electrodes

Journal of the Iranian Chemical Society ◽

10.1007/bf03245775 ◽

2005 ◽

Vol 2 (1) ◽

pp. 1-25 ◽

Cited By ~ 136

Author(s):

B. Šljukić ◽

C. E. Banks ◽

R. G. Compton

Keyword(s):

Electrochemical Reduction ◽

Modified Electrodes ◽

Electrochemical Reduction Of Oxygen ◽

Carbon Based

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Heavy metals determination using various in situ bismuth film modified carbon-based electrodes

Acta Chimica Slovaca ◽

10.1515/acs-2016-0006 ◽

2016 ◽

Vol 9 (1) ◽

pp. 28-35 ◽

Cited By ~ 4

Author(s):

Jozef Sochr ◽

Martina Machková ◽

Ľubomír Machyňák ◽

František Čacho ◽

Ľubomír Švorc

Keyword(s):

Heavy Metals ◽

Modified Electrodes ◽

Wastewater Sample ◽

Bismuth Film ◽

Boron Doped Diamond ◽

Diamond Electrode ◽

Boron Doped ◽

Boron Doped Diamond Electrode ◽

Carbon Based

Abstract The proposed work deals with the utilization of three carbon-based electrode substrates such as boron-doped diamond, glassy carbon and carbon paste for the preparation of in situ bismuth film modified electrodes. Such modified electrodes were subsequently used for the differential pulse anodic stripping voltammetric determination of heavy metal cations (Zn2+, Cd2+ and Pb2+) individually and simultaneously using similar experimental conditions (0.1 mol l−1 acetic buffer solution of pH 4.5 as supporting electrolyte with the addition of 0.1 mmol l−1 Bi3+, deposition potential of −1.4 V and deposition time of 120 s). The results showed that the modification step mostly enhanced the deposition and stripping process of studied cations when compared to the bare electrode substrates. A boron-doped diamond electrode was selected as the substrate for modification and the procedure was applied to the real sample analysis including water sample (certified reference material) and wastewater sample. Using the standard addition method the concentrations of particular heavy metals were quantified and the determined values were in a good agreement with those obtained by the reference method — high resolution atomic absorption spectroscopy with electrothermal atomisation and continual radiation source. This fact highlights that the developed in situ bismuth film modified boron-doped diamond electrode is a suitable electrochemical sensor to be applied to routine analysis of water samples containing heavy metals.

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SEM Cold Stage Techniques for the Observation of Vegetative and Floral Apices of Oat (Avena sativa L.) Plants

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100080377 ◽

1977 ◽

Vol 35 ◽

pp. 590-591

Author(s):

B. K. Kirchoff ◽

L.F. Allard ◽

W.C. Bigelow

Keyword(s):

Critical Point ◽

Avena Sativa ◽

Substantial Improvement ◽

Fresh Tissue ◽

Cold Stage ◽

Critical Point Drying ◽

Almost All ◽

Cell Collapse ◽

Conductive Paint ◽

Carbon Based

In attempting to use the SEM to investigate the transition from the vegetative to the floral state in oat (Avena sativa L.) it was discovered that the procedures of fixation and critical point drying (CPD), and fresh tissue examination of the specimens gave unsatisfactory results. In most cases, by using these techniques, cells of the tissue were collapsed or otherwise visibly distorted. Figure 1 shows the results of fixation with 4.5% formaldehyde-gluteraldehyde followed by CPD. Almost all cellular detail has been obscured by the resulting shrinkage distortions. The larger cracks seen on the left of the picture may be due to dissection damage, rather than CPD. The results of observation of fresh tissue are seen in Fig. 2. Although there is a substantial improvement over CPD, some cell collapse still occurs.Due to these difficulties, it was decided to experiment with cold stage techniques. The specimens to be observed were dissected out and attached to the sample stub using a carbon based conductive paint in acetone.

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