10 research outputs found
Modification of glassy carbon nanoparticles using titanium nanoparticles as a platform for determining diclofenac sodium
This article presents an investigation on the behavior of a chemically modified glassy carbon electrode as a sensing platform for the detection of Diclofenac Sodium. The study also explores the potential application of this electrode in analyzing real samples, including blood, urine, and wastewater. In addition, the synthesis of Titanium Nanoparticles and filaments used in the electrode modification was carried out using a novel method developed by our research group. This unique combination of materials has significantly enhanced the novelty of the technology, as no previous studies have reported such a combination
Composite film as anticorrosive coating of Ti alloys surfaces
Causing important economic damages, the corrosion of the titanium alloys used in the different environmental or medical fields can be prevented by using a physical barrier with anti-corrosion properties. The anti-corrosive property of a film consisting of poly (methyl methacrylate) (PMMA) and ibuprofen (IBU) deposited by dip-coating on Ti alloy surface was investigated by electrochemical impedance spectroscopy method
Cadmium electroanalytical detection at carbon paste modified electrode based on natural clay : [abstract]
Sensitive Detection of Organophosphorus Pesticides Using a Needle Type Amperometric Acetylcholinesterase-based Bioelectrode. Thiocholine Electrochemistry and Immobilised Enzyme Inhibition
International audienceAn acetylcholinesterase (AChE) based amperometric bioelectrode for a selective detection of low concen¬ trations of organophosphorus pesticides has been developed. The amperometric needle type bioelectrode consists of a bare cavity in a PTFE isolated Pt-Ir wire, where the AChE was entrapped into a photopolymerised polymer of polyvinyl alcohol bearing styrylpyridinium groups (PVA-SbQ). Cyclic voltammetry, performed at Pt and AChE/Pt disk electrodes, confirmed the irreversible, monoelectronic thiocholine oxidation process and showed that a working potential of + 0.410 V vs. Ag/AgCl, KClSat was suitable for a selective and sensitive amperometric detection of thiocholine. The acetylthio-choline detection under enzyme kinetic control was found in the range of 0.01-0.3 U cm~" of immobilised AChE. The detection limit, calculated for an inhibition ratio of 10%, was found to reach 5 jxM for dipterex and 0.4 jaIVI for paraoxon. A kinetic analysis of the AChE-pesticide interaction process using Hanes-Woolf or Lineweaver-Burk linearisations and secondary plots allowed identification of the immobilised enzyme inhibition process as a mixed one (non/uncompetitive) for both dipterex and paraoxon. The deviation from classical Michaelis Menten kinetics induced from the studied pesticides was evaluated using Hill plots
Box-behnken experimental design for optimization of voltammentric nanomaterial-modified electrodes : [abstract]
Electrochemical detection of lead at zinc oxide nanostructure based modified electrode
A modified glassy carbon electrode (ZnO-Nafion/GCE) prepared by drop-casting technique, was investigated by square wave anodic stripping voltammetry (SWASV) for the detection of Pb2+ in synthetic and reals water samples
Glassy carbon electrode modified with graphene oxide and gold nanoparticles for ascorbic acid detection
Glassy carbon electrodes modified with graphene oxide (GO), gold nanoparticles (AuNP) and methylene blue (MB) were produced by drop casting method for ascorbic acid (AA) determination. Nafion was used as a polymeric immobilizing matrix. The GCE/GO-AuNP-MB-Nafion and GCE/GO-AuNP-Nafion electrodes were characterized by using cyclic voltammetry and electrochemical impedance spectroscopy to investigate electrocatalytic effect, stability and reproductibility. After optimization, the analytical parameters of the modified electrodes were determined by amperometry. The limit of detection for ascorbic acid at GCE/GO-AuNP-Nafion modified electrode was 2.4 µM and the linear domain from 5 to 50 µM. The electrodes showed significant electrocatalytic effect with good stability and reproductibility
Design and Development of Biosensors for the Detection of Heavy Metal Toxicity
Many compounds (including heavy metals, HMs) used in different fields of industry and/or agriculture act as inhibitors of enzymes, which, as consequence, are unable to bind the substrate. Even if it is not so sensitive, the method for detecting heavy metal traces using biosensors has a dynamic trend and is largely applied for improving the “life quality”, because of biosensor's sensitivity, selectivity, and simplicity. In the last years, they also become more and more a synergetic combination between biotechnology and microelectronics. Dedicated biosensors were developed for offline and online analysis, and also, their extent and diversity could be called a real “biosensor revolution”. A panel of examples of biosensors: enzyme-, DNA-, imuno-, whole-cell-based biosensors were systematised depending on the reaction type, transduction signal, or analytical performances. The mechanism of enzyme-based biosensor and the kinetic of detection process are described and compared. In this context, is explainable why bioelectronics, nanotechnology, miniaturization, and bioengineering will compete for developing sensitive and selective biosensors able to determine multiple analytes simultaneously and/or integrated in wireless communications systems