Recent Advances in the Electrochemical Sensing of Venlafaxine: An Antidepressant Drug and Environmental Contaminant

Synergetic effects of a poly-tartrazine/CTAB modified carbon paste electrode sensor towards simultaneous and interference-free determination of benzenediol isomers

Simultaneous and selective detection of dihydroxy benzene isomers by the synergistic effect of CTAB and tartrazine on a carbon paste electrode (poly-TZ/CTAB/MCPE) sensor by CV and DPV techniques.

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. Electrochemical behaviors of modified and unmodified electrodes were explored with CV method. In addition, DPV was employed for anodic peak and quantitatively detecting sulfite. The DPV results unveiled a linear response of the sensor to various sulfite contents (0.04-565.0 μM) with a narrow detection limit (0.01 μM) and admirable sensitivity (0.0483 μA/μΜ). The diffusion coefficient (D) for sulfite using rGO/PPy NTs-GSPE, 9.9 × 10^-6 cm ²/s was obtained. The sensor was also successful in the sulfite detection in real specimens.

A novel colorimetric and ratiometric fluorescence probe based on 'C-CN' for detection of hydrazine and its imaging in living cells and mouse

Hydrazine plays an important role in chemistry, pharmaceuticals, agriculture and aerospace. However, it is not to be underestimated and has been identified as harmful to the human body. Therefore, it is significant and urgent to develop the detection of hydrazine in vivo and in vitro. Here, the probe TAN was synthesized by using benzothiazole derivatives as the fluorophore and 2,3-diaminomaleonitrile as the identified group to detect hydrazine. The presence of hydrazine resulted in a colorimetric and ratiometric fluorescence response of the probe based on the formation of hydrazone. The detection limit of TAN was 0.31 µM for hydrazine. In addition, the probe TAN was successfully used to visualize hydrazine in living HepG-2 cells and mouse with low cytotoxicity and excellent biocompatibility.

Metal Nanoparticles and Carbon-Based Nanomaterials for Improved Performances of Electrochemical (Bio)Sensors with Biomedical Applications

Monitoring human health for early detection of disease conditions or health disorders is of major clinical importance for maintaining a healthy life. Sensors are small devices employed for qualitative and quantitative determination of various analytes by monitoring their properties using a certain transduction method. A "real-time" biosensor includes a biological recognition receptor (such as an antibody, enzyme, nucleic acid or whole cell) and a transducer to convert the biological binding event to a detectable signal, which is read out indicating both the presence and concentration of the analyte molecule. A wide range of specific analytes with biomedical significance at ultralow concentration can be sensitively detected. In nano(bio)sensors, nanoparticles (NPs) are incorporated into the (bio)sensor design by attachment to the suitably modified platforms. For this purpose, metal nanoparticles have many advantageous properties making them useful in the transducer component of the (bio)sensors. Gold, silver and platinum NPs have been the most popular ones, each form of these metallic NPs exhibiting special surface and interface features, which significantly improve the biocompatibility and transduction of the (bio)sensor compared to the same process in the absence of these NPs. This comprehensive review is focused on the main types of NPs used for electrochemical (bio)sensors design, especially screen-printed electrodes, with their specific medical application due to their improved analytical performances and miniaturized form. Other advantages such as supporting real-time decision and rapid manipulation are pointed out. A special attention is paid to carbon-based nanomaterials (especially carbon nanotubes and graphene), used by themselves or decorated with metal nanoparticles, with excellent features such as high surface area, excellent conductivity, effective catalytic properties and biocompatibility, which confer to these hybrid nanocomposites a wide biomedical applicability.

Recent developments in electrochemical sensors for detecting hydrazine with different modified electrodes

The detection of hydrazine (HZ) is an important application in analytical chemistry. There have been recent advancements in using electrochemical detection for HZ. Electrochemical detection for HZ offers many advantages, e.g., high sensitivity, selectivity, speed, low investment and running cost, and low laboriousness. In addition, these methods are robust, reproducible, user-friendly, and compatible with the concept of green analytical chemistry. This review is devoted to the critical comparison of electrochemical sensors and measuring protocols used for the voltammetric and amperometric detection of the most frequently used HZ in water resources with desirable recovery. Attention is focused on the working electrode and its possible modification which is crucial for further development.