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1.
Environ Sci Pollut Res Int ; 30(33): 80085-80093, 2023 Jul.
Article En | MEDLINE | ID: mdl-37289391

Herein, we introduce a stable and green Au@g-C3N4 nanocomposite as a selective electrochemical sensor for vortioxetine (VOR) determination. The electrochemical behavior of VOR on the developed electrode was investigated through cyclic voltammetry (CV), differential pulse voltammetry (DPV), electrochemical impedance spectroscopy (EIS), and chronoamperometry. The Au@g-C3N4 nanocomposite was thoroughly observed by X-ray diffraction (XRD), energy-dispersive X-ray spectroscopy (EDX), Raman spectroscopy, and scanning electron microscopy. The Au@g-C3N4 nanocomposite had a higher conductivity and a narrower band gap than pure g-C3N4, causing higher electrochemical activity for VOR detection. Moreover, Au@g-C3N4 on the glassy carbon electrode (Au@g-C3N4/GCE) monitored a low level of VOR with high efficiency and low interference as an environmentally friendly processing approach. Interestingly, the as-fabricated sensor exhibited an ultrahigh selectivity for recognizing VOR with a detection limit (LOD) of 3.2 nM. Furthermore, the developed sensor was applied to determine VOR in pharmaceutical and biological samples, which indicated a high selectivity in the presence of interferences. This study suggests new insights into the phytosynthesis synthesis of nanomaterials with excellent biosensing applications.


Graphite , Nanocomposites , Graphite/chemistry , Hyssopus Plant , Vortioxetine , Carbon/chemistry , Electrodes , Nanocomposites/chemistry , Electrochemical Techniques/methods
2.
Mikrochim Acta ; 190(4): 142, 2023 03 18.
Article En | MEDLINE | ID: mdl-36933052

The present study aims to develop an electroanalytical method to determine one of the most significant antineoplastic agents, topotecan (TPT), using a novel and selective molecular imprinted polymer (MIP) method for the first time. The MIP was synthesized using the electropolymerization method using TPT as a template molecule and pyrrole (Pyr) as the functional monomer on a metal-organic framework decorated with chitosan-stabilized gold nanoparticles (Au-CH@MOF-5). The materials' morphological and physical characteristics were characterized using various physical techniques. The analytical characteristics of the obtained sensors were examined by cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS), and differential pulse voltammetry (DPV). After all characterizations and optimizing the experimental conditions, MIP-Au-CH@MOF-5 and NIP-Au-CH@MOF-5 were evaluated on the glassy carbon electrode (GCE). MIP-Au-CH@MOF-5/GCE indicated a wide linear response of 0.4-70.0 nM and a low detection limit (LOD) of 0.298 nM. The developed sensor also showed excellent recovery in human plasma and nasal samples with recoveries of 94.41-106.16 % and 95.1-107.0 %, respectively, confirming its potential for future on-site monitoring of TPT in real samples. This methodology offers a different approach to electroanalytical procedures using MIP methods. Moreover, the high sensitivity and selectivity of the developed sensor were illustrated by the ability to recognize TPT over potentially interfering agents. Hence, it can be speculated that the fabricated MIP-Au-CH@MOF-5/GCE may be utilized in a multitude of areas, including public health and food quality.


Chitosan , Metal Nanoparticles , Metal-Organic Frameworks , Molecular Imprinting , Humans , Molecularly Imprinted Polymers , Chitosan/chemistry , Topotecan , Gold/chemistry , Metal Nanoparticles/chemistry , Electrochemical Techniques/methods , Molecular Imprinting/methods , Limit of Detection , Polymers/chemistry , Carbon/chemistry
3.
Food Chem ; 404(Pt B): 134627, 2023 Mar 15.
Article En | MEDLINE | ID: mdl-36274331

A noninvasive material-based electrochemical sensor continuously monitors the fenamiphos (FMS) level in vegetable samples is highly desirable for innovative fabrics to check the health of agricultural products. Herein, an electrochemical sensor is fabricated by a sensitive molecularly imprinted polymers/metal-organic framework/gold stabilized on graphite carbon nitride (MIP-Au@MOF-235@g-C3N4) for monitoring the FMS level in real samples continuously with high sensitivity and accuracy. The MIP-based sensor was simply produced by a hydrothermal strategy. The MIP-Au@MOF-235@g-C3N4 had a large specific surface area and high catalytic activity, which enables the fabricated sensor with good electrochemical performance with a high sensitivity of 1.07 µA.µM-1 and a wide linear range of 0.01 to 16.4 µM. The proposed strategy was applied to determine FMS in agricultural products with satisfactory recoveries (94.7-107.9%) and a relative standard error of less than 1.0%, providing novel tactics for the rational design ofMIP-sensorsto determine a growing number of deleterious substances.


Biosensing Techniques , Graphite , Metal-Organic Frameworks , Molecular Imprinting , Graphite/chemistry , Gold/chemistry , Molecularly Imprinted Polymers , Electrochemical Techniques , Polymers/chemistry , Limit of Detection , Electrodes
4.
Talanta ; 253: 123991, 2023 Feb 01.
Article En | MEDLINE | ID: mdl-36228557

Tenofovir (TNF) is an antiviral medicine that is utilized to treat the human immunodeficiency virus (HIV). However, its level must be controlled in the human body and environment at the risk of causing kidney and liver problems. Therefore, determining TNF concentration in real samples with more advanced, inexpensive, and accurate sensing systems is essential. In this work, a novel electrochemical nanosensor for TNF determination based on molecularly imprinted polymer (MIP) on the screen-printed electrode modified with functionalized multi-walled carbon nanotubes, graphite carbon nitride, and platinum nanoparticles (MIP-Pt@g-C3N4/F-MWCNT/SPE) was constructed through the electro-polymerization approach. The molecularly imprinted polymers were prepared on the electrode surface with TNF as the template molecule and 2-aminophenol (2-AP) as the functional monomer. Moreover, factors that affect sensor response were optimized. Pt@g-C3N4/F-MWCNT nanocomposite had an excellent synergistic effect on MIP, allowing rapid and specific identification of the test substance. The results demonstrated that the electro-polymerization of 2-AP supplies large amounts of functional groups for the binding of the template molecules, which remarkably enhances the sensitivity and specific surface area of the MIP sensor. This surface enlargement increased the analyte accessibility to imprinted molecular cavities. Under optimum conditions, the oxidation peak current had a linear relationship with TNF concentration ranging from 0.005 to 0.69 µM with a low detection limit of 0.0030 µM (S/N = 3). The results demonstrated that the designed MIP sensor possesses acceptable sensitivity, repeatability, and reproducibility toward TNF determination. Moreover, the developed sensor was applied to biological and water samples to determine TNF, and satisfactory recovery results of 95.6-104.8% were obtained (RSD less than 10.0%). We confirm that combining as-synthesized nanocomposite Pt@g-C3N4/F-MWCNT with MIP improves the limitations of MIP-based nanosensors. The proposed electrode is also compatible with portable potentiostats, allowing on-site measurements and showing tremendous promise as a point-of-care (POC) diagnostic platform.


Anti-HIV Agents , Metal Nanoparticles , Nanotubes, Carbon , Humans , Tenofovir , HIV , Reproducibility of Results , Platinum
5.
Biosensors (Basel) ; 12(9)2022 Sep 19.
Article En | MEDLINE | ID: mdl-36140154

Molecularly imprinted polymers (MIPs) are widely used as modifiers in electrochemical sensors due to their high sensitivity and promise of inexpensive mass manufacturing. Here, we propose and demonstrate a novel MIP-sensor that can measure the electrochemical activity of favipiravir (FAV) as an antiviral drug, thereby enabling quantification of the concentration of FAV in biological and river water samples and in real-time. MOF nanoparticles' application with various shapes to determine FAV at nanomolar concentrations was described. Two different MOF nanoparticle shapes (dodecahedron and sheets) were systematically compared to evaluate the electrochemical performance of FAV. After carefully examining two different morphologies of MIP-Co-Ni@MOF, the nanosheet form showed a higher performance and efficiency than the nanododecahedron. When MIP-Co/Ni@MOF-based and NIP-Co/Ni@MOF electrodes (nanosheets) were used instead, the minimum target concentrations detected were 7.5 × 10−11 (MIP-Co-Ni@MOF) and 8.17 × 10−9 M (NIP-Co-Ni@MOF), respectively. This is a significant improvement (>102), which is assigned to the large active surface area and high fraction of surface atoms, increasing the amount of greater analyte adsorption during binding. Therefore, water-dispersible MIP-Co-Ni@MOF nanosheets were successfully applied for trace-level determination of FAV in biological and water samples. Our findings seem to provide useful guidance in the molecularly imprinted polymer design of MOF-based materials to help establish quantitative rules in designing MOF-based sensors for point of care (POC) systems.


Molecular Imprinting , Amides , Antiviral Agents , Electrochemical Techniques , Electrodes , Metals , Molecularly Imprinted Polymers , Polymers , Pyrazines , Water
6.
Chemosphere ; 308(Pt 1): 135998, 2022 Dec.
Article En | MEDLINE | ID: mdl-35973496

Future energy crises and environmental deterioration may only be avoided by converting solar energy into sustainable, safe, cost-effective, and environmentally friendly technologies such as water splitting. Many researchers and governments throughout the globe have stressed the imperative need for affordable, environmental benign, resistive to corrosion, and earth-abundant nanostructured photocatalysts. This has led scientists to look for a green and cost-effective way to generate energy. As a result, the significance of photo catalyst engineering and reactor design difficulties connected to the performance of the photocatalytic reactions, as well as the examination and analysis of photocatalyst behaviors for adaptable and cost effective H2 production, is emphasized and summarized. The carbon-based materials have an appealing band structure, strong chemical stability, is plentiful on Earth, and is relatively easy to produce, making them suitable for hydrogen production. As example, graphene oxide (GO) with the oxygenated functional groups and graphene and its counterparts, including Graphene quantum dots (GQDs), GO, reduce graphene oxide (rGO), have been demonstrated to be ideal nanocomposite materials due to their superior properties and distribution in matrix and CNTs with excellent electronic transmission efficiency, low cost, stability, and environmental friendly are a great alternative of electron mediators for photocatalytic devices to boost light absorptivity for efficient hydrogen generation but some of them have limited photocatalytic activity due to their low sunlight usage efficiency, therefore the numerous methods, such as doping ions, constructing heterostructure, and functionalizing carbon-based materials, have recently been proven to promote the photocatalytic activity of them. The pore structure of carbon material functions as an acceptor of photogenerated electrons, improved the photocatalyst's specific surface area. Generally low-dimensional carbon materials demonstrated immense promise as highly efficient, low-cost, and environmentally friendly catalysts for hydrogen generation as an energy source. This article reviews the recent research progress on carbon-based materials for hydrogen evolution for the first time. It commences with a quick overview of the present state of affairs and fundamental concepts of hydrogen production in carbon-based nanomaterials for use in this field. We anticipate that this study will inspire readers to expand the use of carbon-based materials in H2 generation in a more environmentally friendly way.


Graphite , Carbon , Graphite/chemistry , Hydrogen/chemistry , Water/chemistry
7.
Environ Res ; 213: 113590, 2022 10.
Article En | MEDLINE | ID: mdl-35690088

In our study, the electrochemical properties of a novel activated nanocomposite were studied with 2-dimensional graphitic carbon nitride/sodium dodecyl sulfate/graphene nanoplatelets on the screen-printed electrodes (2D-g-C3N4/SDS/GNPs/SPE). The as-fabricated sensor exhibited excellent electrochemical performance, including wide dynamic ranges from 0.03 to 1.0 and 1.0-13.5 µM with a low limit of detection (LOD) of 10.0 nM. The fabricated 2D-g-C3N4/SDS/GNPs/SPE electrode exhibited high sensitivity, stability, good reproducibility, reusability, and repeatability towards DOX sensing. It can be utilized in real samples, including human plasma and urine, with excellent correlations and coefficients of variation below 6.0%. Therefore, this study presents potential application values in sensing DOX with efficient performance. Finally, the accuracy was attested by comparison with high-performance liquid chromatography (HPLC) as the reference method, signalizing a good agreement.


Electrochemical Techniques , Nanocomposites , Doxorubicin/analysis , Electrochemical Techniques/methods , Electrodes , Humans , Nanocomposites/chemistry , Reproducibility of Results
8.
Chemosphere ; 303(Pt 3): 135074, 2022 Sep.
Article En | MEDLINE | ID: mdl-35667505

For the quantifiable amounts of Telmisartan (TLM) and Hydrochlorothiazide (HYD) in the presence of Amlodipine (AML) in a ternary mixture of synthetic laboratory mixture, a novel, sensitive, quick, and practical reversed-phase high-performance liquid chromatography (RP-HPLC) method was given. In order to separate, a Waters Spherisorb ODS-2 C18 column was used. For HYD, TLM, and AML, these techniques were viable over linearity ranges of 4-12 µg/mL, 4-25 µg/mL, and 5-40 µg/mL, respectively. The mobile phase system was acetonitrile:methanol: phosphate buffer at pH 2.5 (65:5:30 v/v/v), and the flow rate was 1.5 mL/min. Novel spectrophotometric methods were applied for active substances to determine simultaneously. The first method is absorptivity centering using factorized spectrum, and the second method is dual amplitude difference coupled with absorbance subtraction. These approaches have been effectively applied to bulk, laboratory synthetic mixtures to employ active components quantitatively. Correlation coefficients were found to be higher than 0.99 and the limit of detection values lower than 0.49 µg/mL in both spectrophotometric methods. The methodologies were validated following ICH recommendations. In the developed HPLC method, the limit of detection values was found to be 0.01 µg/mL for HYD and 0.02 µg/mL for AML and TLM. The correlation coefficients for the HPLC method were found to be 0.9971 for HYD, 0.9990 for AML, and 0.9983 for TLM. The suggested HPLC technique is a simple, effective, sensitive, environmentally friendly, and time-saving approach for determining TLM and HYD in the presence of AML.


Amlodipine , Leukemia, Myeloid, Acute , Amlodipine/analysis , Chromatography, High Pressure Liquid/methods , Humans , Hydrochlorothiazide/analysis , Telmisartan
9.
Food Chem Toxicol ; 164: 113080, 2022 Jun.
Article En | MEDLINE | ID: mdl-35490856

A sensitive and novel electrochemical sensor for the detection of Allura Red (AR) in the presence of tartrazine (TRZ) was fabricated using a screen-printed electrode modified by functionalized nanodiamond covered using silicon dioxide and titanium dioxide nanoparticles (F-nanodiamond@SiO2@TiO2/SPE). Scanning electron microscopy (SEM), brunauer-Emmett-teller (BET), energy-dispersive X-ray spectroscopy (EDX), X-ray diffraction (XRD), and Fourier-transform infrared spectroscopy (FT-IR) techniques were performed to characterize the as-synthesized Fnanodiamond@SiO2@TiO2 nanocomposite. The as-fabricated electrode demonstrated two wide dynamic ranges of 0.01-0.12 and 0.12-8.65 µM with a limit of detection (LOD) as low as 1.22 nM. Moreover, the modified electrode exhibits excellent repeatability, reproducibility, reusability, selectivity, and stability with high sensitivity of 44.3 µA µM-1 cm-1, offering good prospects in the simple, cost-effective, and rapid assessment of their total concentration. The successful detection of AR and TRZ, simultaneously and individually in food samples, revealed the applicability of the sensor in the determination of AR and TRZ with satisfactory recovery. Therefore, these advantages provide an excellent possibility for the smart monitoring of AR and TRZ in the future. In the final step, the preferential intercalative binding mode of Allura red with ds-DNA was approved for the first time by a molecular docking study. This study paves the way for engineering highly sensitive DNA biosensors to monitor azo dye compounds by combining the benefits of nanocomposites and valuable information of a molecular docking study.


Nanocomposites , Nanodiamonds , Azo Compounds , Electrochemical Techniques/methods , Electrodes , Molecular Docking Simulation , Nanocomposites/chemistry , Reproducibility of Results , Silicon Dioxide , Spectroscopy, Fourier Transform Infrared , Tartrazine , Titanium
10.
Environ Res ; 212(Pt B): 113264, 2022 09.
Article En | MEDLINE | ID: mdl-35427589

An ultrasensitive and selective voltammetric sensor with ultra-trace level detection limit is introduced for idarubicin (IDA) determination in real samples. The as-synthesized nanocomposite was characterized by several techniques, including Fourier transform infrared spectroscopy (FT-IR), X-ray diffraction (XRD), Raman spectroscopy, Energy-dispersive X-ray spectroscopy (EDX), and Field emission scanning electron microscopy (FE-SEM). The electrocatalytic performance of the developed electrode was observed by cyclic voltammetry (CV), differential pulse voltammetry (DPV), electrochemical impedance spectroscopy (EIS), and chronoamperometry. The limit of detection (LOD) of the developed sensor for idarubicin is 1.0 nM, and the response is found to be in the dynamic concentration range of 0.01-1.9 µmol/L in a Britton-Robinson buffer (B-R, pH = 6.0). Moreover, the fabricated electrode illustrated high selectivity with good repeatability and reproducibility for diagnosing idarubicin as an anthracycline antileukemic drug. Furthermore, to evaluate the validity of the recommended method, three real samples, including human plasma, urine, and water samples, were analyzed with satisfactory recovery and compared with high-performance liquid chromatography (HPLC). The minor groove-binding mode of interaction was also supported by docking simulation studies, emphasizing that IDA can bind to ds-DNA preferably and confirmed experimental results. The reduced assay time and the possibility of measuring a single sample with another anticancer drug without any interference are significant advantages compared to the HPLC. The developed and validated sensor could be a valuable point-of-care diagnostic tool for IDA quantification in patients.


Graphite , Nanospheres , Quantum Dots , Electrochemical Techniques/methods , Graphite/chemistry , Humans , Idarubicin , Limit of Detection , Molecular Docking Simulation , Reproducibility of Results , Spectroscopy, Fourier Transform Infrared
11.
Chemosphere ; 300: 134430, 2022 Aug.
Article En | MEDLINE | ID: mdl-35358553

This work aims to develop an electrochemical sensor for the reusable and selective detection of trace levels of indinavir (IDV) as an anti-retroviral drug by using zinc oxide nano-rods/molybdenum disulfide nanosheets on a screen-printed electrode (ZnO NRs/MoS2 NSs/SPE). Quantitative IDV detection was achieved using differential pulse voltammetry (DPV). The assay specificity was illustrated using interfering species and exhibited high specificity toward the IDV. The developed displayed a wide dynamic range, from 0.01 to 0.66 and 0.66-7.88 µM in Britton-Robinson (B-R) buffer, with a 0.007 µM limit of detection. The fabricated ZnO NRs/MoS2 NSs/SPE electrode exhibited high sensitivity, stability, good reproducibility, and repeatability towards the sensing of IDV. It turned out that the hybrid electrochemical sensor's sensing performance was remarkably improved due to the synergistic effect between MoS2 NSs and ZnO NRs, where the former affords a large active surface area and quick electron transfer. The reported sensor provides a new alternative for electrochemical detection of IDV and could expand the applications of metal nanoparticles in emerging technologies for monitoring drugs in real samples.


Nanotubes , Zinc Oxide , Anti-Retroviral Agents , Disulfides , Electrochemical Techniques , Electrodes , Indinavir , Molybdenum , Reproducibility of Results
12.
Talanta ; 240: 123211, 2022 Apr 01.
Article En | MEDLINE | ID: mdl-34999319

A label-free electrochemical biosensing approach as an appropriate analysis technique for SARS-CoV-2 spike protein (SARS-CoV-2 S-protein) was investigated to facilitate the diagnosis of coronavirus in real samples. It is crucial to construct diagnostic features that can rapidly identify infected individuals to limit the spread of the virus and assign treatment choices. Therefore, a novel and selective method using SiO2@UiO-66 and a label-free electrochemical immunoassay for rapidly detecting spike protein. The development of innovative approaches for direct viral detection employing simplified and ideally reagent-free assays is a pressing and difficult topic. The absence of speedy and effective ways to diagnose viral diseases especially SARS-CoV-2 on demand has worsened the issue of combating the COVID-19 pandemic. The developed electrode illustrated a wide dynamic range of 100.0 fg mL-1 to 10.0 ng mL-1 with low limit detection. Therefore, the as-fabricated electrochemical SARS-CoV-2 S-protein sensor suggests an appropriate perspective in the point-of-care system, within 5.0 min, in nasal samples with satisfactory recovery.


Biosensing Techniques , COVID-19 , Electrochemical Techniques , Humans , Immunoassay , Metal-Organic Frameworks , Pandemics , Phthalic Acids , SARS-CoV-2 , Silicon Dioxide , Spike Glycoprotein, Coronavirus
13.
Chemosphere ; 291(Pt 1): 132807, 2022 Mar.
Article En | MEDLINE | ID: mdl-34762887

The molecularly imprinted polymers (MIP) is an outstanding electrochemical tool that demonstrates good chemical sensitivity and stability. These main advantages, coupled with the material's vast microfabrication flexibility, make molecularly imprinted sensors an attractive sensing device. Herein, it was aimed to develop a state-of-art molecularly imprinted sensor based on CuBi2O4/rGO@MoS2 nanocomposite to be utilized for the detection of linagliptin (LNG), a novel hypoglycemic drug. The electrochemical characterizations of linagliptin on the surface of the modified electrode was examined via cyclic voltammetry (CV), differential pulse voltammetry (DPV), and electrochemical impedance spectroscopy (EIS). Several characterization methods including transmission electron microscope (TEM), X-ray diffraction (XRD), scanning electron microscopy (SEM), Fourier-transform infrared spectroscopy (FT-IR), and Energy-dispersive X-ray spectroscopy(EDX), were utilized for electrode characterization. The LNG imprinted voltammetric sensor was developed in 80.0 mM phenol containing 20.0 mM LNG. CuBi2O4/rGO@MoS2 nanocomposite on LNG imprinted screen-printed carbon electrode (SPCE) (MIP/CuBi2O4/rGO@MoS2 nanocomposite/SCPE) exhibited a linear relationship between peak current and LNG concentration in the range 0.07-0.5 nM with a detection limit of 0.057 nM. In the existence of interfering substances, an LNG imprinted electrode was utilized to analyze urine, human plasma, and tablet samples with adequate selectivity. The developed sensor was also illustrated for stability, repeatability, reproducibility, and reusability.


Molecular Imprinting , Nanocomposites , Electrochemical Techniques , Electrodes , Graphite , Humans , Limit of Detection , Linagliptin , Molybdenum , Reproducibility of Results , Spectroscopy, Fourier Transform Infrared
14.
Chemosphere ; 291(Pt 1): 132809, 2022 Mar.
Article En | MEDLINE | ID: mdl-34785182

This research paper employed an innovative electrochemical electrode to simultaneously determine topotecan (TPT) and mitomycin (MMC) as anticancer agents. For this purpose, a novel nanocomposite was synthesized using a hydrothermal procedure. The nanocomposites were characterized using FTIR, STEM, FESEM, mapping analysis, EDX, and XRD methods. The novelty of this work is the successful synthesis of Fe3O4 decorated on the surface of CuCo2S4 (Fe3O4@CuCo2S4) nanocomposites showed two separate anodic peaks at 0.8 V for TPT and 1.0 V for MMC with potential separation of 0.2 V. This was enough for the simultaneous electrochemical determination of topotecan and mitomycin on a glassy carbon electrode (GCE), simultaneously. At optimized conditions, the developed electrode exhibited linear responses with TPT and MMC concentration in the ranges of 0.01-0.89 and 0.89-8.95 µM for topotecan and 0.1-19.53 µM for mitomycin. The detection limits were observed as 6.94 nM and 80.00 nM for topotecan and mitomycin, respectively. The fabricated Fe3O4@CuCo2S4/GCE showed high sensitivity, long-term stability, and repeatability towards the sensing of TPT and MMC simultaneously and can be utilized in real samples. The obtained results confirmed that the fabricated Fe3O4@CuCo2S4/GCE nanocomposites can be utilize in the simultaneous electrochemical determination of topotecan and mitomycin in real samples.


Antineoplastic Agents , Nanocomposites , Electrochemical Techniques , Electrodes , Limit of Detection , Mitomycin , Topotecan
15.
Mikrochim Acta ; 188(12): 434, 2021 11 27.
Article En | MEDLINE | ID: mdl-34837114

A novel and sensitive voltammetric nanosensor was developed for the first time for trace level monitoring of favipiravir based on gold/silver core-shell nanoparticles (Au@Ag CSNPs) with conductive polymer poly (3,4-ethylene dioxythiophene) polystyrene sulfonate (PEDOT:PSS) and functionalized multi carbon nanotubes (F-MWCNTs) on a glassy carbon electrode (GCE). The formation of Au@Ag CSNPs/PEDOT:PSS/F-MWCNT composite was confirmed by various analytical techniques, including X-ray diffraction (XRD), ultraviolet-visible spectroscopy (UV-Vis), transmission electron microscopy (TEM), energy-dispersive X-ray spectroscopy (EDX), and field-emission scanning electron microscopy (SEM). Under the optimized conditions and at a typical working potential of + 1.23 V (vs. Ag/AgCl), the Au@Ag CSNPs/PEDOT:PSS/F-MWCNT/GCE revealed linear quantitative ranges from 0.005 to 0.009 and 0.009 to 1.95 µM with a limit of detection 0.46 nM (S/N = 3) with acceptable relative standard deviations (1.1-4.9 %) for pharmaceutical formulations, urine, and human plasma samples without applying any sample pretreatment (1.12-4.93%). The interference effect of antiviral drugs, biological compounds, and amino acids was negligible, and the sensing system demonstrated outstanding reproducibility, repeatability, stability, and reusability. The findings revealed that this assay strategy has promising applications in diagnosing FAV in clinical samples, which could be attributed to the large surface area on active sites and high conductivity of bimetallic nanocomposite.


Amides/pharmacology , Antiviral Agents/pharmacology , COVID-19 Drug Treatment , Electrochemistry/methods , Metal Nanoparticles/chemistry , Nanocomposites/chemistry , Nanomedicine/methods , Nanotechnology/methods , Pyrazines/pharmacology , Colloids/chemistry , Electrodes , Gold/chemistry , Humans , Limit of Detection , Linear Models , Nanotubes , Polymers/chemistry
16.
Micromachines (Basel) ; 12(11)2021 Oct 30.
Article En | MEDLINE | ID: mdl-34832746

The accurate and precise monitoring of epirubicin (EPR), one of the most widely used anticancer drugs, is significant for human and environmental health. In this context, we developed a highly sensitive electrochemical electrode for EPR detection based on nickel ferrite decorated with gold nanoparticles (Au@NiFe2O4) on the screen-printed electrode (SPE). Various spectral characteristic methods such as Fourier transform infrared spectra (FT-IR), X-ray diffraction (XRD), field emission scanning electron microscopy (FESEM), transmission electron microscopy (TEM), ultraviolet-visible spectroscopy (UV-Vis), energy-dispersive X-ray spectroscopy (EDX) and electrochemical impedance spectroscopy (EIS) were used to investigate the surface morphology and structure of the synthesized Au@NiFe2O4 nanocomposite. The novel decorated electrode exhibited a high electrocatalytic activity toward the electrooxidation of EPR, and a nanomolar limit of detection (5.3 nM) was estimated using differential pulse voltammetry (DPV) with linear concentration ranges from 0.01 to 0.7 and 0.7 to 3.6 µM. The stability, selectivity, repeatability reproducibility and reusability, with a very low electrode response detection limit, make it very appropriate for determining trace amounts of EPR in pharmaceutical and clinical preparations.

17.
Food Chem Toxicol ; 158: 112698, 2021 Dec.
Article En | MEDLINE | ID: mdl-34838678

In this work, an electrochemical sensor for the azo dye compound tartrazine (TRT) determination was proposed. A screen-printed carbon electrode (SPCE) was modified by depositing three-dimensional porous reduced graphene oxide decorated with carbon quantum dots and platinum nanoparticles (Pt/CQDs@rGO/SPCE). The resulting amount of TRT was observed by differential pulse voltammetry. Under optimal conditions, the sensor exhibited two wide linearities ranging from 0.01 to 1.57 µM and 1.57-9.3 µM with the reliability coefficient of determination of 0.991 and 0.992, respectively. The detection limit (LOD) was also estimated to be 7.93 nM. Moreover, the Pt/CQDs@rGO/SPCE suggested high selectivity in the presence of several interfering agents and azo dye compounds that have a similar structure. Additionally, the Pt/CQDs@rGO/SPCE revealed superior recovery values of about 96.5-101.6% for candy, 99.7-103.5% for soft drinks, 96.0-101.2% for jelly powder, and 98.0-103.0% for water samples. Furthermore, the fabricated sensor exhibits excellent selectivity, stability, reproducibility, and repeatability, indicating a great perspective in the monitoring of TRT. Therefore, it can be speculated that the proposed electrode could be effectively applied to determine TRT in food samples.


Electrochemical Techniques/methods , Graphite/chemistry , Metal Nanoparticles/chemistry , Quantum Dots/chemistry , Tartrazine/analysis , Carbon/chemistry , Electrodes , Limit of Detection , Linear Models , Platinum/chemistry , Porosity , Reproducibility of Results
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