Voltammetric determination of vitamin B6 in the presence of vitamin C based on zinc ferrite nano-particles modified screen-printed graphite electrode.

The zinc ferrite nano-particles (ZnFeO) modified screen-printed graphite electrode (ZnFeO/SPGE) was used for the voltammetric determination of vitamin B in real samples, using differential pulse voltammetry (DPV). It has been found that the oxidation of vitamin B at the surface of such an electrode occurs at a potential about 150 mV less positive compared to an unmodified screen-printed graphite electrode. After optimization, a vitamin B6 sensor with a linear range from 0.

CuFeO nanoparticles-based electrochemical sensor for sensitive determination of the anticancer drug 5-fluorouracil.

A fast and facile electrochemical sensor for the detection of an important anticancer drug, 5-fluorouracil, is fabricated using CuFeO nanoparticles modified screen printed graphite electrode (CuFeO NPs/SPGE). The electrochemical activity of the modified electrode was characterized by chronoamperometry, cyclic voltammetry (CV) and differential pulse voltammetry (DPV) and linear sweep voltammetry (LSV) experiments. The CuFeO NPs improved the electrochemical properties of the electrodes and enhanced their electroanalytical performance.

Electrochemical Sensor Based on Ni-Co Layered Double Hydroxide Hollow Nanostructures for Ultrasensitive Detection of Sumatriptan and Naproxen.

In this work, Ni-Co layered double hydroxide (Ni-Co LDH) hollow nanostructures were synthesized and characterized by X-ray diffraction (XRD), field emission-scanning electron microscopy (FE-SEM), and Fourier-transform infrared spectroscopy (FT-IR) techniques. A screen-printed electrode (SPE) surface was modified with as-fabricated Ni-Co LDHs to achieve a new sensing platform for determination of sumatriptan. The electrochemical behavior of the Ni-Co LDH-modified SPE (Ni-CO LDH/SPE) for sumatriptan determination was investigated using voltammetric methods.

Transition metal dichalcogenides: Synthesis and use in the development of electrochemical sensors and biosensors.

Recent advances in nanotechnology have introduced transition-metal dichalcogenides (TMDs) as inorganic nanomaterials with exceptional properties and structures, suitable also for catalytic applications. The admirable properties of TMDs include the impressive capability of charge transfer, the large surface to volume ratio (S/V), the energy band gap controllable by the number of layers, the strong interaction with light and the mechanical robustness. They are also cost-effective and highly accessible.

Surface amplification of graphite screen printed electrode using reduced graphene oxide/polypyrrole nanotubes nanocomposite; a powerful electrochemical strategy for determination of sulfite in food samples.

The present research presents synthesis and substantial utilization of a nanocomposite of reduced graphene oxide/polypyrrole nanotubes to modify graphite screen printed electrode (rGO/PPy NTs-GSPE) for detection of sulfite. The nanocomposite preparation was done by hydrothermal protocol, followed by characterization by energy-dispersive X-ray (EDX) and field emission-scanning electron microscopy (FE-SEM). Electrocatalytic sensing of sulfite is carried out using differential pulse voltammetric (DPV), linear sweep voltammetry (LSV), cyclic voltammetric (CV), and Chronoamperometry.

Screen-printed graphite electrode modified with CoOnanoparticles and 2D graphitic carbon nitride as an effective electrochemical sensor for 4-aminophenol detection.

We fabricated a new electrochemical 4-aminophenol sensor based on a nanocomposite of CoOnanoparticles and graphite carbon nitride (CoO@g-CN), used for the modification of a screen-printed electrode (CoO@g-CN/SPE). The synthesized nanocomposite was characterized using field-emission scanning electron microscopy, energy-dispersive x-ray spectroscopy, x-ray diffraction and Fourier transform-infrared (FT-IR) techniques. The electro-oxidation of 4-aminophenol in phosphate buffer solution (pH = 7.

A modified carbon paste electrode with N-rGO/CuO nanocomposite and ionic liquid for the efficient and cheap voltammetric sensing of hydroquinone in water specimens.

This paper reports a voltammetric sensor based on copper oxide nanoparticles on nitrogen-doped reduced graphene oxide nanocomposite (N-rGO/CuO)-ionic liquid modified carbon paste electrode (N-rGO/CuO-ILCPE) for determining the hydroquinone (HQ). The N-rGO/CuO was prepared by a facile protocol, followed by characterization via fourier transform-infrared (FT-IR) patterns, field emission-scanning electron microscopy (FE-SEM), energy dispersive X-ray (EDX), and X-ray diffraction (XRD) analysis. The electrochemical behaviour was linearly symmetrical to various hydroquinone levels (1.

Recent advances in carbon nanomaterials-based electrochemical sensors for food azo dyes detection.

Azo dyes as widely applied food colorants are popular for their stability and affordability. On the other hand, many of these dyes can have harmful impacts on living organs, which underscores the need to control the content of this group of dyes in food. Among the various analytical approaches for detecting the azo dyes, special attention has been paid to electro-analytical techniques for reasons such as admirable sensitivity, excellent selectivity, reproducibility, miniaturization, green nature, low cost, less time to prepare and detect of specimens and the ability to modify the electrode.

Graphite carbon nitride-modified screen-printed electrode as a highly sensitive and selective sensor for detection of amaranth.

This work presented a particular electrochemical sensor for analysis of amaranth, an azo toxic dye. A graphite nitride carbon (g-CN) was used to modify an electro-treated screen-printed electrode (g-CN/SPE) for electroanalysis of amaranth. Physicochemical characteristics and analytical performance of g-CN/SPE were investigated by relevant equipment.

A Comprehensive Review of Metal-Organic Framework: Synthesis, Characterization, and Investigation of Their Application in Electrochemical Biosensors for Biomedical Analysis.

Many studies have addressed electrochemical biosensors because of their simple synthesis process, adjustability, simplification, manipulation of materials' compositions and features, and wide ranges of detection of different kinds of biomedical analytes. Performant electrochemical biosensors can be achieved by selecting materials that enable faster electron transfer, larger surface areas, very good electrocatalytic activities, and numerous sites for bioconjugation. Several studies have been conducted on the metal-organic frameworks (MOFs) as electrode modifiers for electrochemical biosensing applications because of their respective acceptable properties and effectiveness.

Amplified electrochemical sensor employing screen-printed electrode modified with Ni-ZIF-67 nanocomposite for high sensitive analysis of Sudan I in present bisphenol A.

This study utilized a facile one-pot protocol to synthesize Ni-cobalt zeolitic imidazolate framework (Ni-ZIF-67) nanocomposite, which was then characterized by Fourier transform infrared spectroscopy, X-ray diffraction, energy dispersive X-ray spectroscopy and scanning electron microscopy. The Ni-ZIF-67 nanocomposite was subsequently applied to modify a screen-printed electrode (SPE) as a durable sensor for detection of Sudan I concomitantly with bisphenol A (BPA), with remarkably increased electrochemical response when comparing with a bare SPE. The results showed the calibration plot to be linear in the concentration range between 0.

Green Synthesis of Zeolitic Imidazolate Frameworks: A Review of Their Characterization and Industrial and Medical Applications.

Metal organic frameworks (MOF) are a class of hybrid networks of supramolecular solid materials comprising a large number of inorganic and organic linkers, all bound to metal ions in a well-organized fashion. Zeolitic imidazolate frameworks (ZIFs) are a sub-group of MOFs with imidazole as an organic linker to metals; it is rich in carbon, nitrogen, and transition metals. ZIFs combine the classical zeolite characteristics of thermal and chemical stability with pore-size tunability and the rich topological diversity of MOFs.

Recent developments in voltammetric and amperometric sensors for cysteine detection.

This review article aims to provide an overview of the recent advances in the voltammetric and amperometric sensing of cysteine (Cys). The introduction summarizes the important role of Cys as an essential amino acid, techniques for its sensing, and the utilization of electrochemical methods and chemically modified electrodes for its determination. The main section covers voltammetric and amperometric sensing of Cys based on glassy carbon electrodes, screen printed electrodes, and carbon paste electrodes, modified with various electrocatalytic materials.

Investigating the role of T helper related cytokines in cerebrospinal fluid for the differential diagnosis of bacterial meningitis in pre-treated paediatric patients.

Given the challenge in the diagnosis of bacterial meningitis (BM), we assessed different cytokines in the cerebrospinal fluid (CSF) of antibiotics pre-treated patients. Laboratory tests and polymerase chain reaction (PCR) were performed for 480 CSF samples from children (2 m to 14 y), suspicious to meningitis and pre-treated with antibiotics, to detect bacterial and viral aetiologies. Sixty-one CSF were included and the levels of 13 cytokines such as IL-2, IL-4, IL-5, IL-6, IL-9, IL-10, IL-13, IL-17A, IL-17F, IL-21, IL-22, IFN-γ and TNF-α were measured using flow-cytometry.

A joint experimental and theoretical investigation of kinetics and mechanistic study in a synthesis reaction between triphenylphosphine and dialkyl acetylenedicarboxylates in the presence of benzhydrazide.

Stable crystalline phosphorus ylides were obtained in excellent yields from the 1:1:1 addition reaction between triphenylphosphine (TPP) and dialkyl acetylenedicarboxylates, in the presence of NH-acids, such as benzhydrazide. To determine the kinetic parameters of the reactions, they were monitored by UV spectrophotometery. The second order fits were automatically drawn and the values of the second order rate constant (k(2)) were calculated using standard equations within the program.