Electrochemical sensors, due to their excellent and unique features, are of high interest nowadays for the detection and monitoring of several biological compounds. In such a case, serotonin (SRN), ...an important neurotransmitter, was herein studied for its detection in biological fluids since its presence is more crucial to be monitored and detected in clinical and medical applications. Several study strategies have been used to determine the chemical and physical properties. The crystalline size of the constructed copper sulfide (Cu2S) material was measured to be 25.92 nm. The Cu2S was fabricated over the working surface and further analyzed for several sensor parameters to be optimized. The charge transfer resistance of the copper sulfide-modified glassy carbon electrode (Cu2S/GCE) was determined to be about 277.0 Ω. With the linear range from about 0.029 μM to 607.6 μM for SRN, the limit of detection (LOD) was calculated as 3.2 nM, with a good sensitivity of 13.23 μA μM−1 cm2. The sensor experienced excellent repeatability, reproducibility, and long-term stability. The fabricated electrode was selective with the presence of different interfering compounds. The real sample analysis, as determined with the regular addition method with human serum and urine samples, revealed a good recovery percentage. Thus, the employed fabricated electrode material will be highly effective in sensing other analytes of choice.
In this paper, we grab to utilize one of the trending techniques with efficient implications in wastewater treatment of organic pollutants, the photocatalytic degradation method shining out in the ...research field. Herein, tin (Sn)–doped zinc oxide (ZnO) nanoparticles (NPs) (Sn/ZnO) with different doping concentrations (1, 2, 3, 4, and 5 wt%) were synthesized via a simple co-precipitation assisted method and later subjected for their physico-chemical, morphological, and optical characterization. In addition, photocatalytic activity as the concerned study was investigated as to record the different doping levels of Sn/ZnO to examine the effect of doping concentration in relation with the degradation efficiency. We know that the optical bandgap of pure ZnO was 3.26 eV while it tends to increase slightly upon increasing the doping concentration. In the present investigation, methylene blue (MB) dye was used as a model pollutant to evaluate the photocatalytic activity of Sn/ZnO photocatalysts under natural sunlight. Varied doping concentrations of Sn/ZnO were compared with different characterization techniques while XRD analysis shows up 4-Sn/ZnO with sharp peak at (1 0 1) plane with smaller grain size in comparison to other Sn/ZnO samples. The morphological recognition depicts the hexagonal structure with smaller size for 4-Sn/ZnO which offers more active sites with improved photocatalytic activity, higher surface area for the transportation of pollutants. Fluorescence spectra results revealed that Sn dopant suppresses the charge carrier recombination. The lower intensity of PL indicated reduced recombination rate, which resulted in enhancing the photocatalytic activity. To investigate the possible mechanism, kinetics and reusability studies were performed. The 4% Sn-doped ZnO nanoparticle concentration showed highest photocatalytic activity when compared with other doping levels.
Laser-induced graphene (LIG) has gained dominance recently as a very sought after material for fabrication, patterning graphitic structures, and electrodes for various applications in electronics. In ...this study, we increase the ability of RGO-graphitized nanosheets by carefully regulating the laser fluence. We used an advanced cutting-edge technique for direct writing with a pulse laser in an open atmosphere to reduce graphite oxide nanosheets in aqueous media. The nano-sized RGO was confirmed as being produced by converting the sp
3
structure to sp
2
reduced form. The laser-induced RGO-1-3 were characterized by field emission scanning electron microscopy (FESEM), transmission electron microscopy (TEM), Raman spectroscopy, Fourier transform infrared (FTIR), powder X-ray diffraction (XRD), and X-ray photoelectron spectroscopy (XPS). Non-agglomerated and different porous nanostructures of RGO-1-3 were successfully obtained during laser irradiation. Electrochemical impedance spectroscopy (EIS) was performed and high surface-active edge reactive regions were found after laser irradiation of the RGO nanostructures, which promoted excellent electrochemical detection performance with rapid electron transfer, in a low potential window. All LI-RGO nanostructures were fabricated on GCE to determine their capacity for the precise detection of acetaminophen using CV and DPV voltametric techniques. In particular, the RGO-3/GCE fabricated electrode exhibited the lowest level of 5.2 nanomolar detection of acetaminophen with an outstanding sensitivity of 2.7271 μA Mm
−1
cm
−2
. The designed RGO-3/GCE electrode also exhibited remarkable reproducibility, selectivity, and stability. In addition, the RGO-3/GCE device was successfully investigated for the detection of an antipyretic pharmaceutical drug in river and human urine samples and showed excellent results. In the search for acetaminophen, the RGO-3/GCE fabricated device can be a low-cost and reliable RGO GCE electrode.
Laser-induced graphene (LIG) has gained dominance recently as a very sought after material for fabrication, patterning graphitic structures, and electrodes for various applications in electronics.
The widespread usage of levofloxacin (LVF) intake is executed for several urinary and respiratory systems infections in human. But, its over intake leads to severe damage to humans and the ...environment by its exposure. Hence the detection of LVF is concerned and we herein developed an electrocatalyst, strontium tungsten oxide nanospheres and later decorated onto the functionalized multiwall carbon nanotubes (SrWO4/f-MWCNT) to perform effective electrochemical recognition of LVF in aquatic and biological samples. Binary metal oxide with carbon composite SrWO4/f-MWCNT was developed due to its specific features as nanostructures. Various methods of investigation have been examined to identify the physiochemical characteristics like X-ray diffraction, Raman spectroscopy, Fourier transform infrared spectroscopy, X-ray photoelectron spectroscopy, and morphological characteristics including field emission scanning electron microscopy, and transmission electron microscopy. The synthesized SrWO4/f-MWCNT sample crystalline size was around 32.9 nm. The SrWO4/f-MWCNT modified glassy carbon electrode (GCE) has been subjected to electrochemical investigation with a wide linear range of 0.049 μM to 574.73 μM with good sensitivity 2.86 μA μM-1 cm2, the limit of detection at 14.9 nM for LVF sensing. Furthermore, the designed LVF detection exhibited excellent anti-interference, stability, reproducibility, and repeatability. The as-developed sensor's electrochemical outcomes indicate the superior performance inherent in the developed composite.
Display omitted
•Strontium tungstate decorated f-MWCNT was employed for the sensing of levofloxacin.•The physico-chemical and morphological study of the samples results with the pure crystallinity and sphere-like nanoparticles with nanotubes.•The obtained linear range from 0.049 – 574.73 μM shows a lower detection limit of about 0.0149 μM with a sensitivity about 2.86 μAμM-1cm-2.•The fabricated sensor will be an efficient levofloxacin sensor with selective and stable responses.•The designed composites will be more sustainable in both environmental and biological samples.
The earth-abundant, cost-effective, easier preparation of zinc phosphate eases its diverse implications in recent applications. We have synthesized two-dimensional niobium carbide (NbC)-encapsulated ...zinc phosphate Zn2P2O7. The physicochemical characteristics were determined, which demonstrate pure crystallinity and good integration of the composite samples. To improve and develop a sustainable environment, the Zn2P2O7/NbC composite will be an efficient material. The detection of pharmaceutical compounds is highly preferable in clinical approaches. The importance of serotonin (SER) has empowered sensor development with the fabricated Zn2P2O7-based electrode. The synergistic action prevailing in the composite material endowed the active sites with improved electrocatalytic activity. The increased addition of SER was acquired with two linear ranges from 0.019 to 563.68 μM. The lower detection limit was obtained as 0.0055 μM toward the exposed SER addition at a lower concentration, and the sensitivity was about 7.72 μA μM–1 cm–2. Analyses of other parameters such as repeatability, reproducibility, and stability indicate the excellent performance of the electrode. The presence of SER in human urine and blood serum samples can be identified very easily, and hence, analysis of real samples was performed. The as-obtained recovery results stated the excellent performance of the fabricated sensor.
The modern development in the agricultural production has huge influential factors being highly beneficial and also includes some health hazards. Under the class of chlorophenols, ...2,4,6-trichlorophenol is a widely used chemical which remains as a major pollutant in the environment. The detection of 2,4,6-trichlorophenol was initiated as a controlling measure to decrease the seriousness prevailing in the ecosystem. The electrochemical and UV–vis absorption sensing platform are simple and low-cost detection techniques with precise and sensitive analysis. Cadmium tin oxide integrated with the reduced graphene oxide was employed as a nanohybrid for the construction of the working electrode. The structural and morphological analysis confirmed the high degree of crystallinity of the nanocomposite with nanorod formation. The high surface area, with high charge carrier mobility, and increased electrical conductivity of the material boosted the 2,4,6-trichlorophenol detection. The active surface area was calculated to be 0.068 cm−1, 0.089 cm−1, 0.118 cm−1 and 0.146 cm−1 for all the modified electrodes. The resistance of the electrodes was about 91.4 Ω, 72.9 Ω, 48.8 Ω and 41.6 Ω. The linear range of 2,4,6-trichlorophenol was 0.019 μM–0.299 μM and 1.299 μM–1678.97 μM in electrochemical sensing and 10.99 μM–24.84 μM in UV detection. The obtained limit of detection with the formulation 3σ/SD was about 3.05 nM and 80 nM with sensitivity about 14.01 μA μM−1 cm−2. The real sample detection in environmental real samples showed good recovery results. The specific selectivity, good repeatability, reproducibility and stability analysis proves the good sensing parameters. Thus, the fabricated electrode is highly sufficient of sensing 2,4,6-trichlorophenol. These excellent features of the material can be applied for several other applications which will provide good performances.
Display omitted
•Binary n-n hetrostructured perovskite integrated with rGO was constructed.•The dual sensing of 2,4,6-TCP was capable with the catalyst cadmium tin oxide/rGO.•LOD 3.05 nM (DPV) and 80 nM (UV), and sensitivity about 14.01 μA μM−1 cm−2 was observed.•The spiked environmental samples showed good recovery results.
In the present study, we have designed a highly conductive electrode material niobium carbide (NbC) entangled with copper phosphate (Cu3P2O8). The combined features of the efficient electrocatalyst ...with improved electrical conductivity, more active sites, with a high surface area were employed for the electrochemical sensing of melatonin (MLT). MLT is a naturally secreted hormone in our brain responsible for maintaining our daily circadian cycle. The detection of such hormones in clinical studies can help maintain several problems. The Cu3P2O8/NbC was initially characterized to analyze the physicochemical properties. The high crystalline Cu3P2O8 resembled a self-assembled flake ball-like structure entangled with NbC sheets. The synergistic effect between the catalyst enhances the electrochemical performance of MLT. The Cu3P2O8/NbC fabricated glassy carbon electrode obtained an enhanced oxidation response of MLT. The linearity range of MLT was about 0.014–1517.68 μM with a low limit of detection of about 0.0083 μM. The fabricated electrode showed high selectivity to the interfering compounds added and the sensitivity was about 5.137 μA μM–1 cm–2. The real samples showed good results at the Cu3P2O8/NbC/GCE. The Cu3P2O8/NbC/GCE will be more efficient and reliable in detecting the employed drugs or any other analytes of choice. Thus, the low cost, with improved electrochemical performances and significant features of the prepared electrode will be of great interest.
•The metal chalcogenides were Ag2Se anchored on β-cd/rGO for the detection of azithromycin (AMN).•The structural and morphological analysis of the samples were performed.•The linear range of AMN was ...0.023971.7 µM showing lower detection limit about 0.0045 μM with the sensitivity about 14.25 µA µM−1 cm−2.•The fabricated sensor exhibits excellent sensing performances toward AMN detection.•The developed composite will be more sustainable in biological and environmental samples.
The harmful impact of long-term consumption of antibiotic drugs, especially azithromycin (AMN) is given more importance in this study. Antibiotics in both soil and water possess a long lifespan, can be bio-accumulative, and are harmful to aquatic life and to people's health. To resolve this problem, a detecting substrate made up of silver selenide (Ag2Se) integrated over functionalized β-cyclodextrin (β-cd) polymer with reduced graphene oxide (rGO) was designed.
X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR), Raman spectroscopy, and field emission scanning electron microscopy (FE-SEM) with EDX has been employed to investigate the hybridized composite material Ag2Se/β-cd/rGO. Moreover, the assembled material has been employed for electrochemical sensing that can detect the commonly used AMN.
The outcomes indicate that the sensor has outstanding activity, exhibiting a limit of detection (LOD) of 0.0045 nM with a wide linear working range of 0.023–971.7 μM. The sensor showed a good sensitivity of about 14.25 µA µM−1 cm−2. Thus, the Ag2Se/β-cd/rGO modified GCE for AMN sensing showed outstanding anti-interference, reproducibility, repeatability, and stability results. In addition, while studying practical application samples including human serum and urine, industrial water, and pharmaceutical tablets, the sensor's performance exhibited a significant recovery ability. Hence, Ag2Se/β-cd/rGO/GCE will be a cost-effective material for easier detection of AMN.
Display omitted
Our daily activities are in control and functioned by the neurotransmitter that helps in balancing the signals send to the brain. Epinephrine (EPN) is a commonly known neurotransmitter and the ...imbalance in EPN leads to several dysfunctions and diseases. Moreover, the uptake of EPN and the importance of EPN have provoked the need for the detection of EPN. Such detection will be helpful in the diagnostics and clinical monitoring of the diseases. The electrode material with intriguing properties for the detection is important and was designed. The niobium carbide (NbC) with silver/silver phosphate (Ag/AgPO) with interesting physical and chemical properties was synthesized. The physical and structural analysis of Ag/AgPO/NbC was characterized by different analytical techniques. The electrochemical detection of EPN was executed after the physicochemical presence of the material. The specific surface area, and high electrical conductivity, with improved active sites enhances the electrochemical performance of EPN. With these properties, the fabricated electrode records a lower limit of detection of about 0.004 μM with a linear range of 0.09–422.45 μM and the sensitivity was about 9.25 μAμM−1cm−2. The other parameter analysis such as repeatability, reproducibility, and stability showed excellent performances at Ag/AgPO/NbC/screen-printed carbon electrode. The real sample analysis with human serum and urine samples also had good recovery results. Thus, the Ag/AgPO/NbC nanocomposite is highly efficient with all these unique features which can be employed in several applications in near future.
Display omitted
•The integration of Ag/AgPO heterostructures with niobium carbide was built for the detection of epinephrine.•The disposable screen-printed carbon electrode modified with Ag/AgPO/NbC electrode highly shows superior electrochemical performances.•The linear range of epinephrine was 0.09–422.45 μM.•The acquired limit of detection was 0.004 μM with a sensitivity of about 9.25 μA/μM/cm2.•Thus, the fabricated sensor exhibits excellent sensing performances toward epinephrine detection.
