A sensitive and stable acetylcholinesterase biosensor with TiO nanoparticles anchored on graphitic carbon nanofibers for determination of organophosphate pesticides.

Electrode materials play a central role in assembling biosensors. In this work, a titanium dioxide nanoparticle loaded graphitized carbon nanofiber (TiO/GNF) composite is prepared for the sensitive detection of organophosphorus pesticide residues (OPs). The TiO/GNF composite with superior conductivity, catalytic activity and biocompatibility offers an extremely hydrophilic surface for the effective immobilization of acetylcholinesterase (AChE).

Selective and simultaneous sensing of ascorbic acid, dopamine and uric acid based on nitrogen-doped mesoporous carbon.

Development of novel sensing nanostructures for facile, economical and fast applications has attracted more and more interest. Herein, a nitrogen-doped mesoporous carbon (NMC) was synthesized by pyrolyzing a mixture of melamine and carbon black at a low-temperature (600 °C) and exploited for the simultaneous sensing of ascorbic acid (AA), dopamine (DA) and uric acid (UA). The as-made NMC exhibits a rougher surface and smaller size than carbon black.

A sensitive pyrimethanil sensor based on porous NiCoS/graphitized carbon nanofiber film.

With the extensive use of pesticides, the problem of pesticide residues has become people's concern. In this work, NiCoS nanoneedle arrays grown on an electrospun graphitized carbon nanofiber film (NiCoS/GCNF) is successfully prepared by a simple two-step hydrothermal method, and further applied to detection of fungicide pyrimethanil (PMT). NiCoS arrays exhibit a unique core-shell structure with rough surface, providing abundant electrochemically active sites exposed to the electrolyte.

A Sensitive Pyrimethanil Sensor Based on Electrospun TiC/C Film.

Titanium carbide (TiC) is a very significant transition metal carbide that displays excellent stability and electrical conductivity. The electrocatalytic activity of TiC is similar to noble metals but is much less expensive. Herein, carbon nanofibers (CNFs)-supported TiC nanoparticles (NPs) film (TiC/C) is prepared by electrospinning and carbothermal processes.

Flexible and conductive titanium carbide-carbon nanofibers for the simultaneous determination of ascorbic acid, dopamine and uric acid.

The development of novel materials for facile, cost-effective and quick practical application is a demanding research interest in electroanalytical chemistry. Titanium carbide (TiC), as one of the most important transition metal carbides, exhibits good chemical stability and electrical conductivity, and its electrocatalytic activity resembles that of metals, but is much cheaper. In this work, TiC nanoparticle (NP) loaded carbon nanofiber (CNF) films (TCNFs) are synthesized using an electrospinning and carbothermal technique, which facilely maintains their structural integrity with robust adhesion.

Flexible polypyrrolone-based microporous carbon nanofibers for high-performance supercapacitors.

Flexible materials have drawn considerable attention due to the demand for wearable and flexible electronic products. Seeking new kinds of precursors for preparing carbon nanofibers with good flexibility for high-performance supercapacitors is a hot issue. In this work, a flexible polypyrrolone (BBB)/polyimide (PI) composite-based carbon nanofiber membrane (PBPICF) is prepared by a facile electrospinning and carbonization process.

Hierarchically mesostructured porous TiO hollow nanofibers for high performance glucose biosensing.

Effective immobilization of enzymes on an electrode surface is of great importance for biosensor development, but it still remains challenging because enzymes tend to denaturation and/or form close-packed structures. In this work, a free-standing TiO hollow nanofibers (HNF-TiO) was successfully prepared by a simple and scalable electrospun nanofiber film template-assisted sol-gel method, and was further explored for glucose oxidase (GOD) immobilization and biosensing. This porous and nanotubular HNF-TiO provides a well-defined hierarchical nanostructure for GOD loading, and the fine TiO nanocrystals facilitate direct electron transfer from GOD to the electrode, also the strong interaction between GOD and HNF-TiO greatly enhances the stability of the biosensor.

Nitrogen-Doped Carbon Nanotubes Supported by Macroporous Carbon as an Efficient Enzymatic Biosensing Platform for Glucose.

Effective immobilization of enzymes/proteins on an electrode surface is very essential for biosensor development, but it still remains challenging because enzymes/proteins tend to form close-packed structures on the electrode surface. In this work, nitrogen-doped carbon nanotubes (NCNTs) supported by three-dimensional Kenaf Stem-derived porous carbon (3D-KSC) (denoted as 3D-KSC/NCNTs) nanocomposites were constructed as the supporting matrix to load glucose oxidase (GOD) for preparing integrated glucose biosensors. These NCNTs are vertically arrayed on the channel walls of the 3D-KSC via the chemical vapor deposition method, which could noticeably increase the effective surface area, mechanical stability, and active sites (originating from the doped nitrogen) of the nanocomposites.

PdCo alloy nanoparticle-embedded carbon nanofiber for ultrasensitive nonenzymatic detection of hydrogen peroxide and nitrite.

PdCo alloy nanoparticle-embedded carbon nanofiber (PdCo/CNF) prepared by electrospinning and thermal treatment was employed as a high-performance platform for the determination of hydrogen peroxide and nitrite. The as-obtained PdCo/CNF were characterized by transmission electron microscopy, energy-dispersive X-ray spectroscopy and X-ray diffraction. Electrochemical impedance spectroscopy, cyclic voltammetry and differential pulse voltammetry were employed to investigate the electrochemical behaviors of the resultant biosensor.

Pd-Ni alloy nanoparticle/carbon nanofiber composites: preparation, structure, and superior electrocatalytic properties for sugar analysis.

Novel Pd-Ni alloy nanoparticle/carbon nanofiber (Pd-Ni/CNF) composites were successfully prepared by a simple method involving electrospinning of precursor polyacrylonitrile/Pd(acac)2/Ni(acac)2 nanofibers, followed by a thermal process to reduce metals and carbonize polyacrylonitrile. The nanostructures of the resulting Pd-Ni/CNF nanocomposites were carefully examined by a combination of scanning electron microscopy (SEM), transmission electron microscopy (TEM), high resolution transmission electron microscopy (HRTEM), high-angle annular dark field (HAADF)-scanning transmission electron microscopy (STEM), energy dispersive X-ray (EDX), thermogravimetric analysis (TGA), X-ray diffraction (XRD), and X-ray photoelectron spectra (XPS). For all the nanocomposites, the Pd-Ni alloy nanoparticles (NPs) were dispersed uniformly and embedded firmly within the framework or on the surface of CNF.

Human cytochrome P450 3A4 and a carbon nanofiber modified film electrode as a platform for the simple evaluation of drug metabolism and inhibition reactions.

Electrochemical biosensors consisting of cytochrome P450 enzyme modified electrodes have been developed to provide a simple method for screening the metabolism of a drug and its inhibitor. Here, we report a very simple electrochemically driven biosensor for detecting drug metabolism and its inhibition based on cytochrome P450 3A4 (CYP3A4) and a carbon nanofiber (CNF) modified film electrode without any other modified layers such as mediator films. Direct electron transfer (DET) between CYP3A4 and CNFs was observed at a formal potential of -0.

Improved direct electrochemistry for proteins adsorbed on a UV/ozone-treated carbon nanofiber electrode.

We studied the direct electron transfer (DET) of proteins on a carbon nanofiber (CNF) modified carbon film electrode by employing the one-step UV/ozone treatment of CNF. This treatment changed the CNF surface from hydrophobic to hydrophilic because a sufficient quantity of oxygen functional groups was introduced onto the CNF surface. Furthermore, this simple approach increased both the effective surface area and the number of edge-plane defect sites.

Simultaneous determination of three β-blockers at a carbon nanofiber paste electrode by capillary electrophoresis coupled with amperometric detection.

In the paper, a novel carbon nanofiber paste electrode (CFPE) was fabricated and firstly used as a sensitive amperometric detector in capillary electrophoresis (CE) for the simultaneous determination of three β-blockers: sotalol, alprenolol and atenolol. Compared with the bare carbon paste electrode, the CFPE exhibited enhanced oxidation peak current responses to the analytes due to its excellent electrocatalytic activities, high conductivity and large effective surface area. Subsequently, effects of several important factors such as detection potential, pH and concentration of running buffer, separation voltage and injection time on the analysis were investigated.

Enzyme-free ethanol sensor based on electrospun nickel nanoparticle-loaded carbon fiber paste electrode.

We have developed a novel nickel nanoparticle-loaded carbon fiber paste (NiCFP) electrode for enzyme-free determination of ethanol. An electrospinning technique was used to prepare the NiCF composite with large amounts of spherical nanoparticles firmly embedded in carbon fibers (CF). In application to electroanalysis of ethanol, the NiCFP electrode exhibited high amperometric response and good operational stability.

Growth of carbon nanostructures on carbonized electrospun nanofibers with palladium nanoparticles.

This paper studies the mechanism of the formation of carbon nanostructures on carbon nanofibers with Pd nanoparticles by using different carbon sources. The carbon nanofibers with Pd nanoparticles were produced by carbonizing electrospun polyacrylonitrile (PAN) nanofibers including Pd(Ac)(2). Such PAN-based carbon nanofibers were then used as substrates to grow hierarchical carbon nanostructures.