Electrochemical Detection Of Serotonin Research Articles

Highly sensitive and selective detection of serotonin and dopamine with stable oxidation potentials using novel Dy2MoO6 nanosheets

Simultaneous detection of serotonin and dopamine is quite difficult due to their less oxidation potential difference which interferes redox reactions at the modified electrode. To overcome this issue, the temperature-dependent hydrothermal method has been adopted for the synthesis of Dy2MoO6 nanosheets with different morphology. Crystal structure, morphology, and surface properties of Dy2MoO6 nanosheets have been investigated using PXRD, FE-SEM, and XPS analysis. The electrochemical behavior of nanosheets has been examined using CV, LSV, and EIS spectroscopy. Electrochemical detection of serotonin and selectivity has been carried out using DPV and amperometric techniques. The limit of detection (LOD) for serotonin was found to be 4.1 nM with the linear range of 10–130 nM. From the simultaneous detection analysis, the LOD for dopamine was found to be 8.3 nM with the linear range of 20–340 nM. The selectivity of serotonin against ascorbic acid, glucose, acetylcholine, dopamine, and H2O2 confirmed the insubordinate behavior of the modified electrode for the interference except for serotonin. As prepared sensing system was also successfully applied for serotonin detection in human blood and urine samples as a practicality test. As a result, the present sensing system could be applicable for the biological and pharmaceutical samples analysis.

Composite films based on copper nanoparticles and nickel phthalocyanine as electrochemical sensors for serotonin detection

Electrochemical sensors for detecting neurotransmitters have been extensively explored owing to the versatility and low cost of electrochemical techniques. Although serotonin (5-HT) is a very important neurotransmitter, very few studies have investigated its electrochemical detection. Herein, the use of layer-by-layer (LbL) films, containing layers of copper nanoparticles alternating with nickel phthalocyanine in indium-doped tin-oxide electrodes, for electrochemically detecting 5-HT is proposed. Copper nanoparticles were synthesized and characterized based on size, zeta potential, and spectroscopic behavior in the ultraviolet–visible (UV–Vis) region. Subsequently, the films were produced and characterized by UV–Vis spectroscopy and cyclic voltammetry. The electrochemical response of the films was evaluated as a function of the supporting electrolyte, number of adsorbed layers, material adsorption sequence, stability, electrochemical mechanism, and other parameters. In the electrochemical detection of serotonin, the developed material exhibited high sensitivity and specificity for 5-HT compared to some interferents such as ascorbic acid, hydrogen peroxide, cysteine, sulfamethoxazole, and aspartic acid. The results showed a 400% increase in the current densities of the film in the presence of 20 µmol•L−1 of 5-HT. The electrochemical signal recorded for 5-HT was unaffected even in the presence of ascorbic acid at the same concentration. The sensor exhibited a linear response over a wide concentration range (0.35–135 µmol•L−1) and a low detection limit (0.13 µmol•L−1) for 5-HT. Furthermore, the developed electrode enables successive 5-HT analyses without requiring new films. The material reported herein is promising for 5-HT electrochemical analysis in biological samples.

Development of a new highly sensitive serotonin sensor based on green synthesized silver nanoparticle decorated reduced graphene oxide.

Electrochemical detection of serotonin (5-hydroxytryptamine, 5-HT) is proposed for the first time using a cost-effective and eco-friendly nanocomposite of AgNPs and rGO which is synthesized through an in situ green reduction process using rosemary leaf extract. The synthesized nanocomposite and the elaborate thin layers have been characterized using UV-Vis, FTIR, TEM, and EIS. The sensitivity of the developed sensor was evaluated by differential pulse voltammetry. The peak current measured at a voltage of 420 mV (vs. Ag/AgCl) increased linearly in the 0.1 nM to 100 µM concentration range. A very low limit of detection of 78 pM compared to those in recent studies reported in the literature was obtained. The innovative approach was successfully applied to the determination of serotonin in spiked artificial urine samples.

Electrochemical Detection of Serotonin Using t-ZrO2 Nanoparticles Modified Carbon Paste Electrode

Synthesis of zirconium oxide (zirconia) (ZrO2) nanoparticles (ZNPs) through gel combustion technique as well as their structural and morphological characterization using XRD, SEM and TEM forms the central theme of this work. Along with structural and morphological characterization, an electrochemical detection of Serotonin (5-HT) is described using ZNPs Modified Carbon Paste Electrode (ZMCPE). The XRD results confirms that particles are well crystallized in tetragonal phase with average particle size of 35 nm. From SEM it can be observed that, the materials formed is porous in nature and the particles are seems to be uniform in size. HRTEM reveals that, the particles size in the order of 30–40 nm and the crystallinity was supported by SAED pattern of the ZNPs and these results are in close agreement with the results obtained through XRD. The Electrochemical detection of Serotonin (5-HT) was performed through cyclic voltammetric and differential pulse voltammetric method at different circumstances like concentration of the analyte, applied potentials and pH of the medium. The DPV experiments shows that ZMCPE displays high sensitivity for the quantification of serotonin (5-HT) in the range 10–50 μM and the limit of detection is 0.585 μM. The ZMCPE gives good reproducibility, high catalytic activity and sensitivity for the electrochemical quantification of Serotonin.

Electrochemical detection of serotonin in the presence of 5-hydroxyindoleacetic acid and ascorbic acid by use of 3D ITO electrodes

The reproducible detection of neurotransmitters such as serotonin in the presence of interfering substances is still a topic in analytical sciences. In the present study, a 3D mesoporous ITO electrode (μITO) has been used for the determination of serotonin in the presence of high concentrations 5-hydroxyindoleacetic acid (5-HIAA) as an alternative to carbon materials. The 3D structure has been prepared via a template approach, by spin coating on top of a flat ITO electrode. It is mechanically stable allowing application in a flow cell. The detection of serotonin on μITO shows a significant decrease of the oxidation potential from 670mV to 350mV vs. Ag/AgCl compared to flat ITO and an improvement in the stability of the signal. The sensitivity has been evaluated by DPV (20nA/μM) and is linear in the range of 50μM and 1mM. The detection limit (LOD) was calculated and is 7.5μM for μITO. Furthermore, a clear discrimination of serotonin to 5-hydroxyindoleacetic acid – an enzymatic degradation product of serotonin – and an anodic interfering substance – ascorbic acid – can be observed.

Electrochemical Detection of Neurotransmitters Using Modified PEDOT Electrodes

The electrochemical detection of serotonin (5-HT) and dopamine (DA) in the presence of ascorbic acid (AA), was investigated at poly[3,4-ethylenedioxythiophene], PEDOT, and PEDOT-Au electrodes. We could show that the technique used for preparing the PEDOT and the PEDOT-Au electrodes strongly affects the quality of the sensors. Pulse plating gave the best films with regard to their morphology and stability.

Electrochemical Detection of Serotonin Using Conductive Diamond Electrodes

Abstract The electrochemical detection of serotonin with highly boron-doped diamond thin film electrodes was investigated by use of flow injection analysis (FIA) with amperometric detection. The voltammetric behavior of diamond indicated low background current and a low tendency to adsorb the oxidative products on the electrode surface, in comparison to the glassy carbon electrode. An experimental amperometric detection limit of 10 nM (0.2 pmol) was obtained for the FIA technique, demonstrating that diamond is a stable and sensitive electrode for serotonin determination.

Immunohistochemical and electrochemical detection of serotonin in the nervous system of Fasciola hepatica, a parasitic flatworm

The head region of the trematode parasite Fasciola hepatica contains47 ± 0.42pmol/mg wet wt. of serotonin as measured by high-performance liquid chromatography coupled to electrochemical detection. The head region includes the cerebral ganglia, the transverse commissure and associated nervous tissue that innervates the musculature of the oral sucker, pharynx and body wall. Tissue from the tail, which contains little nervous innervation, has approximately 20 times less serotonin (0.18 ± 0.01pmol/mg wet wt.). Immunohistochemistry was used to identify serotonin-like immunoreactive cells. Bipolar and multipolar cell bodies in the cerebral ganglia show serotonin-like immunoreactivity. Also evident are serotonin-like immunoreactive processes in the neuropile and in the transverse commissure that concepts the ganglia, and immunoreactive peripheral bipolar cell bodies innervating the musculature of the pharynx and body wall. The cell bodies containing serotonin are organized in bilateral symmetry with homologous cell bodies and processes represented in each ganglion and on both sides of the pharynx.

Immunohistochemical and electrochemical detection of serotonin in the nervous system of the blood‐feeding bug, Rhodnius prolixus

AbstractThe distribution of serotonin throughout the nervous system of the blood‐feeding bug Rhodnius prolixus has been studied using immunohistochemistry and reversed‐phase high‐performance liquid chromatography coupled to electrochemical detection.Approximately 150 serotonin‐like immunoreactive neurons are distributed throughout the central nervous system. These neurons are distributed over both ventral and dorsal surfaces and are found in all ganglia. Several of these neurons appear to be homologous to previously described serotonin‐like immunoreactive neurons in insects. These include a large pair of bilaterally symmetrical neurons that project axons out of the suboesophageal ganglion, and some serially homologous neurons which project contralaterally and appear to be interneurons.Immunoreactive branches and varicosities are found in the neuropile of all ganglia, and immunoreactive axons are found in all interganglionic connectives. Several of the peripheral nerves are covered in a plexus of immunoreactive processes. These processes result in a meshwork of fine varicose branches lying superficially over the peripheral nerves, which resemble neurohemal areas.The central nervous system of Rhodnius contains about 5.5 pmol serotonin unequally distributed between the ganglia. The highest content is found in the brain and optic lobes, and the lowest content is found in the prothoracic ganglion. Substantial amounts of serotonin are present in the corpus cardiacum and in the peripheral nerves possessing the serotonin‐like neurohemal areas. Serotonin is released from these latter neurohemal areas in a calcium‐dependent manner in response to high‐potassium saline.It is concluded that serotonin plays an important central and peripheral role in this insect.