Publications by authors named "Abbas Afkhami"

126 Publications

QSAR analysis on a large and diverse set of potent phosphoinositide 3-kinase gamma (PI3Kγ) inhibitors using MLR and ANN methods.

Sci Rep 2022 04 12;12(1):6090. Epub 2022 Apr 12.

Chemometrics Laboratory, Chemistry Department, Faculty of Science, University of Kurdistan, Sanandaj, Iran.

Phosphorylation of PI3Kγ as a member of lipid kinases-enzymes, plays a crucial role in regulating immune cells through the generation of intracellular signals. Deregulation of this pathway is involved in several tumors. In this research, diverse sets of potent and selective isoform-specific PI3Kγ inhibitors whose drug-likeness was confirmed based on Lipinski's rule of five were used in the modeling process. Genetic algorithm (GA)-based multivariate analysis was employed on the half-maximal inhibitory concentration (IC) of them. In this way, multiple linear regression (MLR) and artificial neural network (ANN) algorithm, were used to QSAR models construction on 245 compounds with a wide range of pIC (5.23-9.32). The stability and robustness of the models have been evaluated by external and internal validation methods (R 0.623-0.642, RMSE 0.464-0.473, F 40.114, Q 0.600, and R 0.011). External verification using a wide variety of structures out of the training and test sets show that ANN is superior to MLR. The descriptors entered into the model are in good agreement with the X-ray structures of target-ligand complexes; so the model is interpretable. Finally, Williams plot-based analysis was applied to simultaneously compare the inhibitory activity and structural similarity of training, test and validation sets.
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http://dx.doi.org/10.1038/s41598-022-09843-0DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC9005662PMC
April 2022

Simultaneous determination of BoNT/A and /E using an electrochemical sandwich immunoassay based on the nanomagnetic immunosensing platform.

Chemosphere 2022 Jul 17;298:134358. Epub 2022 Mar 17.

Chemical Injuries Research Center, Systems Biology and Poisonings Institute, Baqiyatallah University of Medical Sciences, Tehran, Iran. Electronic address:

Developing new ultrasensitive assays for the detection of the presence, and determination of the serotype of the most poisonous material known i.e. botulinum neurotoxin (BoNT) is vital to human health and the wellbeing of the surrounding environment. Here, an electrochemical sandwich immunoassay with high sensitivity is adopted to achieve simultaneous determination of BoNT serotypes A and E based on [email protected]/Cd and Ag nanoparticles acting as monoclonal antibody labels. Two well-separated peaks with strong electrochemical signals are generated by the labels, allowing for the simultaneous detection of two analytes existing on the electrode. To obtain well-oriented polyclonal antibodies immobilization, boronic acid is directly attached to the magnetic core/metal-organic framework (MOF) shell nanoagent surfaces without the requirement of a long and flexible spacer. Accordingly, it is possible to directly detect the metal ion labels through square wave voltammetry without the metal pre-concentration step. This results in distinct and well-defined voltammetric peaks, pertaining to each sandwich-type immunocomplexes. The limits of detection of BoNT/A and BoNT/E analyses were found to be 0.04 and 0.16 pg mL with the linear dynamic ranges of 0.1-1000 and 0.5-1000 pg mL, respectively. Based on the obtained results, this immunosensor has the wide linear ranges, while also exhibiting low limits of detection along with good stability and reproducibility.
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http://dx.doi.org/10.1016/j.chemosphere.2022.134358DOI Listing
July 2022

Application of [email protected] nanobeads in microextraction by packed sorbent (MEPS) for determination of BTEXs biomarkers by HPLC-UV in urine samples.

J Chromatogr B Analyt Technol Biomed Life Sci 2022 May 7;1197:123197. Epub 2022 Mar 7.

Department of Biostatistics, School of Public Health and Research Center for Health Sciences, Hamadan University of Medical Sciences, Hamedan, Iran.

A relatively new adsorbent based on covalent organic frameworks (COFs) was employed for the first time to extract and determine Trans, trans-muconic acid (tt-MA), Mandelic acid (MA), Hippuric acid (HA), and 3-Methylhippuric acid (m-MHA) in urine. For this purpose, microextraction was performed using the packed sorbent (MEPS) method. Following the extraction process, the prepared samples were specified via the high-performance liquid chromatography-ultraviolet detector system. The precipitation polymerization was applied to synthesize the [email protected] nanobeads, and the morphological and dimensional structures of the products were specified with FE-SEM images. Some key variables affecting the extraction efficiency (i.e., sample volume, elution volume, condition and washing solvents, type and volume of elution solvent, extraction cycles, temperature, and pH of the sample solution) were investigated. In ideal conditions, the limit of detection (LOD) was obtained from 0.02 µg/ml for tt-MA to 0.5 µg/ml for MA. Calibration curves (at five-point) were plotted in the range 0.05-5 µg/ml for tt-MA to 1-300 µg/ml for MA (R > 0.98). Moreover, intra- and inter-day precision values were 3.1-5.5 and 4.6-9.8%, respectively. The developed method was successfully employed to determine four analytes in three concentrations (low, medium, and high QCs). The results showed a satisfactory recovery (70-87%). COF-MEPS technique is a rapid, easy, user-friendly, and environment-friendly method for separating the minimum values of all BTEXs chief biomarkers from urine samples without using complicated processes and only with one adsorbent. Also, it can be a good alternative for biomonitoring the workers exposed to BTEX compounds in occupational and environmental access.
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http://dx.doi.org/10.1016/j.jchromb.2022.123197DOI Listing
May 2022

PVP-coated silver nanocubes as RRS probe for sensitive determination of Haloperidol in real samples.

Spectrochim Acta A Mol Biomol Spectrosc 2022 May 11;272:121025. Epub 2022 Feb 11.

Faculty of Chemistry, Bu-Ali Sina University, Hamedan 6517838695, Iran.

Polyol synthesis of silver nanocubes (Ag NCs) under dark conditions yielded nanoparticles with high uniformity and purity, as well as edge lengths of 42 nm with good stability and scattering cross-section. These nanoparticles were characterized by SEM, TEM, and Uv-vis spectroscopy. The presence of polyvinylpyrrolidone (PVP) as a capping agent on the surface of Ag NCs, as well as its satisfactory interaction level with Haloperidol (Hp) as an antipsychotic drug, has led to the use of these nanoparticles as Resonance RayleighScattering (RRS) probe to measure Hp. Indeed, Hp resulted in reducing the RRS signal of Ag NCs, and this change in RRS intensity was linear in the range of 10.0 to 800.0 µg L of Hp. The limits of detection (LOD) and quantification (LOQ) were found to be 1.5 and 5.0 µg L, respectively. The influence of interfering species was studied, and it was found that the suggested method has good selectivity and can be used to monitor Hp in actual samples. As a result, this RRS probe operated well in determining Hp in pharmaceutical and human plasma samples with satisfactory recovery.
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http://dx.doi.org/10.1016/j.saa.2022.121025DOI Listing
May 2022

Wearable Potentiometric Sensor Based on NaMnO for Non-invasive Monitoring of Sodium Ions in Sweat.

Anal Chem 2022 02 20;94(4):2263-2270. Epub 2022 Jan 20.

Chemical Injuries Research Center, Systems Biology and Poisonings Institute, Baqiyatallah University of Medical Sciences, Tehran 1435916471, Iran.

Here, we present a wearable potentiometric ion sensor for real-time monitoring of sodium ions (Na) in human sweat samples using NaMnO as the sensing material. NaMnO is an attractive material for developing wearable electrochemical sensors due to its good Na incorporation ability, electrical conductivity, stability, and low fabrication cost. In the first step, the analytical performance of the electrode prepared using NaMnO is presented. Then, a miniaturized potentiometric cell integrated into a wearable substrate is developed, which reveals a Nernstian response (58 mV dec). We achieved the detection of Na in the linear ranges of 0.21-24.54 mmol L, which is well within the physiological range of Na. Finally, for on-body sweat analysis, the potentiometric sensor is fully integrated into a headband textile. This platform can be employed for non-invasive analysis of Na in human sweat for healthcare and disease diagnosis.
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http://dx.doi.org/10.1021/acs.analchem.1c04960DOI Listing
February 2022

Controlled Transdermal Iontophoresis of Insulin from Water-Soluble Polypyrrole Nanoparticles: An In Vitro Study.

Int J Mol Sci 2021 Nov 19;22(22). Epub 2021 Nov 19.

Research Institute of Oncology and Hematology, Cancer Care Manitoba, University of Manitoba, Winnipeg, MB R3E 3P4, Canada.

The iontophoresis delivery of insulin (INS) remains a serious challenge due to the low permeability of the drug through the skin. This work aims to investigate the potential of water-soluble polypyrrole nanoparticles (WS-PPyNPs) as a drug donor matrix for controlled transdermal iontophoresis of INS. WS-PPyNPs have been prepared via a simple chemical polymerization in the presence of sodium dodecyl sulfate (SDS) as both dopant and the stabilizing agent. The synthesis of the soluble polymer was characterized using field emission scanning electron microscopy (FESEM), dynamic light scattering (DLS), fluorescence spectroscopy, and Fourier transform infrared (FT-IR) spectroscopy. The loading mechanism of INS onto the WS-PPyNPs is based on the fact that the drug molecules can be replaced with doped dodecyl sulfate. A two-compartment Franz-type diffusion cell was employed to study the effect of current density, formulation pH, INS concentration, and sodium chloride concentration on anodal iontophoresis (AIP) and cathodal iontophoresis (CIP) of INS across the rat skin. Both AIP and CIP delivery of INS using WS-PPyNPs were significantly increased compared to passive delivery. Furthermore, while the AIP experiment (60 min at 0.13 mA cm) show low cumulative drug permeation for INS (about 20.48 µg cm); the CIP stimulation exhibited a cumulative drug permeation of 68.29 µg cm. This improvement is due to the separation of positively charged WS-PPyNPs and negatively charged INS that has occurred in the presence of cathodal stimulation. The obtained results confirm the potential applicability of WS-PPyNPs as an effective approach in the development of controlled transdermal iontophoresis of INS.
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http://dx.doi.org/10.3390/ijms222212479DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8621898PMC
November 2021

Crystal violet-modified HKUST-1 framework with improved hydrostability as an efficient adsorbent for direct solid-phase microextraction.

Mikrochim Acta 2021 Aug 26;188(9):305. Epub 2021 Aug 26.

Faculty of Chemistry, Bu-Ali Sina University, Hamedan, Iran.

Metal-organic frameworks (MOFs) have received extensive attention in adsorption applications owing to their high surface area. However, some MOFs do not perform well as the extraction medium when used under aqueous conditions. The low hydrostability of MOFs limits the practical application of these materials in solid-phase microextraction (SPME). Here, the fabrication of a water resistance SPME fiber coating is introduced based on the crystal violet (CV)-modified HKUST-1 framework on copper ([email protected]@CV). The HKUST-1 was prepared by the in situ growth method, followed by post-synthetic modification of HKUST-1 with the CV layer. The preparation of the modified HKUST-1 was characterized by FESEM, XRD, FTIR, and DFT approaches. The prepared SPME coating was successfully employed for the quantification of anthracene (AN), as a model analyte, in water samples. The limit of detection was 0.8 ng mL. The developed method will open up a new door towards searching for promising materials in SPME applications.
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http://dx.doi.org/10.1007/s00604-021-04966-zDOI Listing
August 2021

Electrochemical sandwich-type immunosensor for the detection of PSA based on a trimetallic AgAuPt nanocomposite synthesized using the galvanic replacement reaction.

Anal Methods 2021 09 28;13(33):3676-3684. Epub 2021 Jul 28.

Research and Development Department, Farin Behbood Tashkhis LTD, Tehran, Iran.

A sandwich-type electrochemical immunoassay was introduced for the determination of the prostate-specific antigen (PSA) biomarker. A direct and simple galvanic replacement reaction was performed between the Ag framework and metallic salts of tetrachloroauric(iii) acid trihydrate and chloroplatinic acid to produce a trimetallic composite of AgAuPt. The trimetallic composite of AgAuPt was applied to the preparation of the capture layer of the immunoassay for stabilizing the primary Ab at the surface of the prepared composite. The immunoassay detection layer was also prepared using a labeled antibody containing a bimetallic composite of AgPt as a label. The various procedures in the immunoassay fabrication were monitored step by step using cyclic voltammetry and electrochemical impedance spectroscopy. Also, the electrochemical determination of PSA was performed using differential pulse voltammetry in the presence of the ferrocene redox probe and HO. Furthermore, the effective parameters in the fabrication of the immunoassay included the drop volume of the AgAuPt trimetallic composite and the incubation time for the immobilization of biomolecules (i.e., Ab, BSA, PSA, and labeled Ab), and the concentration of HO were optimized during the determination of PSA. Then, the determination of PSA was performed under optimized conditions. It could be seen that there was a linear relation between the PSA concentration and DPV responses in the concentration range of 50 pg mL to 500 ng mL and the limit of detection (LOD) for the proposed immunoassay was calculated as 17.0 pg mL. In the following investigation, the cross-reactivity of the proposed immunoassay was studied in the presence of BSA, CEA, IgG, and human hepatitis surface antigen, in which the results showed a negligible change in the performance of the immunoassay.
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http://dx.doi.org/10.1039/d1ay01004bDOI Listing
September 2021

Target -responsive host-guest binding-driven dual-sensing readout for enhanced electrochemical chiral analysis.

Analyst 2021 Jul;146(15):4865-4872

Faculty of Chemistry, Bu-Ali Sina University, Hamedan 6517838695, Iran.

Achieving efficient chiral discrimination by a convenient method remains a challenge in pharmaceutical and biotechnology industries. Our aim in this paper was to develop a dual-signaling enantioselective sensing strategy based on the competitive binding assay. A combination of β-cyclodextrin (β-CD) and methylene blue (MB) was used as an enantioselective discrimination probe to develop a straightforward electrochemical chiral sensor using the drug naproxen (R-and S-NaX) as the representative enantiomers. The principle relied on the difference between two enantiomers in the ability to replace a pre-binding redox probe, which in turn resulted in different dual signals for the two enantiomers. The applicability of the optimized procedure was demonstrated by the analysis of NaX enantiomers in the range of 0.4-6.0 μM. Featuring both signal-on and signal-off elements, the electrode presented significantly enhanced electrochemical activity with a low limit of detection (LOD) of 0.07 μM. We expect that our work will inspire interesting engineering strategies for developing novel enantioselective electrochemical sensors.
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http://dx.doi.org/10.1039/d1an00795eDOI Listing
July 2021

Development of modified polymer dot as stimuli-sensitive and Ga radio-carrier, for investigation of in vitro drug delivery, in vivo imaging and drug release kinetic.

J Pharm Biomed Anal 2021 Sep 17;203:114217. Epub 2021 Jun 17.

Faculty of Chemistry, Bu-Ali Sina University, Hamedan 6517838695, Iran; D-8 International University, Hamedan, Iran.

A polymer dot modified histidine-functionalized graphene quantum dot carrier, [email protected], was synthesized to investigate the in vitro sunitinib (STB) deliveryvia luminescence spectrometer. The carrier's synthesis, with an average size of 34 nm, was proved by Fourier transform infrared (FTIR), Transmission Electron Microscopy (TEM), and Dynamic Light Scattering (DLS) analyses. In the in vitro, STB delivery investigation showed that for healthy tissue, the STB was loaded at pH  = 7.2 and at 25  = 5.4 at 37 °C with a maximum loading efficiency percentage of 99 % while it was released at pH = 5.4 at 37 °C with a release percentage of 97 %. In the sequel, the STB loaded carrier was labeled with Gallium-67 ([email protected]) to produce exceedingly transparent radio-carrier for in vivo kidney cancerous mice imaging via the single photon emission computed tomography (SPECT) device. The radiochemical purity of the [email protected] was obtained as 95 % by Radio Thin Layer Chromatography (RTLC) and High-Performance Liquid Chromatography (HPLC) analysis. All obtained results affirmed that the synthesized [email protected] is an STB stimuli-sensitive and selective targeting carrier. All cancerous mice in vivo images at 10 and 20 h of [email protected] post-injection and its bio-distribution calculations showed its most accumulation in the kidney cancerous tissue. Also, the STB release kinetic was studied via Zero-order, First-order, Higuchi, and Korsmeyer-Peppas models, and the release data were fitted with Korsmeyer-Peppas model that expresses the STB release mechanism is controlled by diffusion.
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http://dx.doi.org/10.1016/j.jpba.2021.114217DOI Listing
September 2021

Short-term effect of multi-pollutant air quality indexes and PM on cardiovascular hospitalization in Hamadan, Iran: a time-series analysis.

Environ Sci Pollut Res Int 2021 Oct 25;28(38):53653-53667. Epub 2021 May 25.

Faculty of Chemistry, Bu-Ali Sina University, Fahmideh Av, Hamadan, 65174, Iran.

Air pollutants are the most important environmental factors that contributed to cardiovascular disease (CVD). The present study aimed to investigate the number of hospitalization due to heart failure (HF) and myocardial infarction (MI) following the air pollutant exposure using a time-series regression analysis with a distributed lag model in Hamadan, Iran (2015-2019). A total of 2091 cases of CVD were registered. Based on the findings, the highest health effects on HF hospitalization were observed with air quality health index (AQHI) at lag 9 (RR = 1.043, 95% CI 0.991-1.098), and air quality index (AQI) at lags 2, 7, and 9 (RR = 1.001, 95% CI 0.998-1.002), for an increase in 1 unit of the indexes, and with PM at lag 0 (RR = 1.001, 95% CI 0.996-1.004) for 10 μg/m increase in PM levels. The highest health effects on MI hospitalization were calculated with AQHI at lag 10 (RR = 1.059, 95% CI 1.001-1.121) and AQI at lags 1 and 2 (RR = 1.001, 95% CI 0.998-1.002), for an increase in 1 unit of the indexes, and with PM at lag 8 (RR = 1.002, 95% CI 0.997-1.005) for 10 μg/m increase in PM levels. According to a seasonal classification, results showed that hospitalization in the warm season was higher than that of the cold season. Based on our knowledge, the current study is the first study that investigated the effect of air quality indexes on hospitalization due to HF and MI in Iran. Findings can provide basic information to plan preventive measures for reducing exposure chance and hospitalization rate in high-risk people.
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http://dx.doi.org/10.1007/s11356-021-14386-4DOI Listing
October 2021

Flexible electrospun nanofibrous film integrated with fluorescent carbon dots for smartphone-based detection and cellular imaging application.

Spectrochim Acta A Mol Biomol Spectrosc 2021 Nov 11;260:119944. Epub 2021 May 11.

Faculty of Chemistry, Bu-Ali Sina University, Hamedan, Iran.

The dose of administered chemotherapy drugs is crucial to determine due to the potential for efficient or adverse outcomes for cancer patients. To date, no user-friendly and low-cost method of doxorubicin (DOX) detection using nontoxic and biodegradable materials has been reported. For this reason, in this work, we have developed for the first time a nanofiber-based sensing platform for sensitive and on-site DOX assay in just 10 min. This is obtained thanks to printable, porosity and embeddability features of electrospun nanofibrous films (ENFFs) combined with nitrogen and sulfur co-doped carbon dots (NS-CDs) as sensing probes. The assay was done by just pipetting analyte on the hydrophilic spots of the fabricated photoluminescence water-stable ENFFs where the color intensity was being darkened. DOX quenched NS-CDs fluorescence onto ENFFs through inner filter effect. The developed sensor was either coupled with smartphone technology to provide miniaturized, portable and easy-to-use device or an ordinary spectrofluorimeter for solid-state sensing applications (detection limit of 5.4 nM). Moreover, applicability of the designed sensor was evaluated in human serum with satisfactory recoveries. It is more interesting that the fabricated NS-CDs/ENF scaffolds have a high potential to detect the intracellular DOX to enhance cell proliferation leading to be considered as a multimodal tool in biomedical research and clinical diagnostics.
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http://dx.doi.org/10.1016/j.saa.2021.119944DOI Listing
November 2021

Self-assembled graphene-based microfibers with eclectic optical properties.

Sci Rep 2021 Mar 9;11(1):5451. Epub 2021 Mar 9.

Faculty of Chemistry, Bu-Ali Sina University, Hamedan, 6517838695, Iran.

The construction of graphene-based microfibers with reinforced mechanical and electrical properties has been the subject of numerous researches in recent years. However, the fabrication of graphene-based fibers with remarkable optical features still remains a challenge and has not been addressed so far. This paper aims to report a series of flexible self-assembled fibers, synthesized through a few-minute sonication of thermally oxidized graphene oxide nanosheets, so-called Nanoporous Over-Oxidized Graphene (NOG), in an acidic medium. These free-standing glassy fibers were classified into four distinct morphological structures and displayed a collection of intriguing optical properties comprising high transparency, strong birefringence, fixed body colorations (e.g. colorless, blue, green, and red), tunable interference marginal colorations, UV-visible-near IR fluorescence, and upconversion emissions. Moreover, they exhibited high chemical stability in strongly acidic, basic, and oxidizing media. The foregoing notable attributes introduce the NOG fiber as a promising candidate both for the construction of graphene-based photoluminescent textiles and the development of a wide variety of optical applications.
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http://dx.doi.org/10.1038/s41598-021-84940-0DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7943562PMC
March 2021

Application of magnetic ion imprinted polymers for simultaneous quantification of Al and Be ions using the mean centering of ratio spectra method.

Talanta 2021 Apr 17;225:122003. Epub 2020 Dec 17.

Faculty of Chemistry, Bu-Ali Sina University, Hamedan, Iran.

Magnetic solid-phase extraction (MSPE) coupled with the spectrophotometric method for the simultaneous quantification of aluminum and beryllium ions based on mean centering of ratio (MCR) method is reported in the current work, for the first time. Two new magnetic ion-imprinted polymers (MIIPs) were synthesized using Chrome Azurol S as the ligand, (3-aminopropyl)triethoxysilane (APTES) as the functional monomer, tetraethyl orthosilicate (TEOS) as the cross-linker, and aluminum and beryllium ions as the templates, and used as magnetic sorbents. The characteristic properties of MIIPs were investigated using FT-IR spectroscopy, field emission scanning electron microscopy (FE-SEM), low angle X-ray powder diffraction (XRD), and energy-dispersive x-ray spectroscopy (EDS). Through this study, factors influencing the MSPE were studied and optimized. The proposed method exhibited good performance, with the linearity of 5.0-50.0 ng mL for aluminum ion and 2.0-40.0 ng mL for beryllium ion as well as the detection limits (DLs) of 3.2 and 0.9 ng mL for aluminum and beryllium ions, respectively. At the end of the study, the capability of the developed method for determination of target analytes was evaluated by its application in the tap and river water samples.
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http://dx.doi.org/10.1016/j.talanta.2020.122003DOI Listing
April 2021

Application of magnetic nanomaterials in electroanalytical methods: A review.

Talanta 2021 Apr 9;225:121974. Epub 2020 Dec 9.

Faculty of Chemistry, Bu-Ali Sina University, Hamedan, Iran. Electronic address:

Magnetic nanomaterials (MNMs) have gained high attention in different fields of studies due to their ferromagnetic/superparamagnetic properties and their low toxicity and high biocompatibility. MNMs contain magnetic elements such as iron and nickel in metallic, bimetallic, metal oxide, and mixed metal oxide. In electroanalytical methods, MNMs have been applied as sorbents for sample preparation before the electrochemical detection (sorbent role), as the electrode modifier (catalytic role), and the integration of the above two roles (as both sorbent and catalytic agent). In this paper, the application of MNMs in electroanalytical methods have been classified based on the main role of the nanomaterial and discussed separately. Furthermore, catalytic activities of MNMs in electroanalytical methods such as redox electrocatalytic, nanozymes catalytic (peroxidase, catalase activity, oxidase activity, superoxide dismutase activity), catalyst gate, and nanocontainer have been discussed.
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http://dx.doi.org/10.1016/j.talanta.2020.121974DOI Listing
April 2021

Phase distribution and risk assessment of PAHs in ambient air of Hamadan, Iran.

Ecotoxicol Environ Saf 2021 Feb 22;209:111807. Epub 2020 Dec 22.

Faculty of Chemistry, Bu-Ali Sina University, Hamedan, Iran. Electronic address:

In the present study, both gaseous and particulate (PM with dae <2.5 µm) phases of polycyclic aromatic hydrocarbons (PAHs) were measured in the ambient air of Hamadan city, Iran. For this reason, two low-volume samplers equipped with glass fiber filters were used for sampling of particulate phase (N = 30) and XAD-2 sorbent tubes were applied for sampling gaseous phase of PAHs (N = 30). The sampling was conducted during warm and cold seasons in 2019. The average of cold/warm season ratios for ΣPAH and PM concentrations were 1.14 and 0.62, respectively. Summed PAHs concentration were determined to be in the range 0.008-59.46 (mean: 11.61) ng/m and 0.05-40.83 (mean: 10.22) ng/m for the cold and warm seasons, respectively. A negative Pearson correlation coefficient was obtained for wind speed and relative humidity. The average Benzo (a) Pyrene equivalent carcinogenic (BaP) levels in the cold season were lower than the maximum permissible risk level of 1 ng/m for BaP. The BaP toxicity equivalency (ΣBaP) and BaP mutagenicity equivalency (ΣBaP) appeared to be significantly higher in the cold season (averaging 0.35 and 1.65 ng/m, respectively) than those in warm season. Health risk assessment was performed for children and adults based on BaP, inhalation cancer risk. The diagnostic ratios of individual PAHs concentration showed that the significant sources of PAH emissions may be related to light duty vehicles (LDVs) in Hamadan. Although, some other sources such as pyrogenic source and petrol combustion were also suggested.
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http://dx.doi.org/10.1016/j.ecoenv.2020.111807DOI Listing
February 2021

Ultrasound-assisted dispersive liquid antisolvent precipitation for extraction of polar organic compounds in water.

Anal Chim Acta 2020 Oct 20;1135:91-98. Epub 2020 Aug 20.

Department of Analytical Chemistry, Faculty of Chemistry, Bu-Ali Sina University, Hamedan, Iran.

This paper reports on the development of an extraction method called "ultrasound-assisted dispersive liquid antisolvent precipitation (UA-DLAP)". The developed method is a combination of dispersive liquid-liquid microextraction (DLLME) and liquid antisolvent precipitation (LAP) methods. Unlike DLLME, the extraction solvent in UA-DLAP is replaced with a bad solvent for the analyte which has a low affinity toward the analyte (antisolvent). Unlike LAP, in UA-DLAP the analyte is dissolved in water, the antisolvent is water-immiscible and denser than water, and the needed volume of the antisolvent is in microliter range. In UA-DLAP, after the addition of a mixture of the antisolvent and a disperser solvent to the sample solution under sonication, a cloudy mixture containing the antisolvent micro/nanodroplets appears. After centrifugation of the mixture, three phases appear (a water-rich phase in the top, an analyte rich precipitate phase in middle, and an antisolvent rich phase in the bottom). Finally, the analyte rich precipitate phase is separated and dissolved in a back-extraction solvent. To evaluate the efficiency of the UA-DLAP method and its possible mechanism of action, three model polar organic compounds in water were extracted by UA-DLAP and determined spectrophotometrically. The results showed that the precipitate phase for all of the investigated analytes was nanostructured. The limits of detection were 22 ng mL, 11 ng mL, and 3.9 ng mL for doxorubicin, methylene blue, and Congo red, respectively. Respective experimental enrichment factors were 18.3, 27.8, and 31.1.
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http://dx.doi.org/10.1016/j.aca.2020.08.027DOI Listing
October 2020

NiZnFeO nanoparticles-decorated poly (vinyl alcohol) nanofiber as resonance light scattering probe for determination of sunitinib in serum samples.

Talanta 2020 Oct 21;218:121190. Epub 2020 May 21.

Faculty of Chemistry, Bu-Ali Sina University, Hamedan, Iran. Electronic address:

Nickel zinc ferrite (NiZnFeO) nanoparticles decorated poly (vinyl alcohol) was constructed by the electrospinning method and used for determining the sunitinib amount in real sample. In this study, resonance light scattering (RLS) technique was used for studying the interaction of nanofibers with sunitinib. Similar NiZnFeO nanoparticles-decorated nanofibers with average diameter of 200 nm and length up to several millimeters were prepared. The morphology and microstructure of the as prepared Ni Zn FeO nanoparticles-decorated nanofibers were studied in details. The nanofibers were characterized by energy dispersive X-ray spectroscopy, scanning electron microscopy, and transmission electron microscopy techniques. The nanofibers are formed through assembling magnetic nanoparticles with poly (vinyl alcohol) as the structure-directing template. Under the optimal conditions, the linear dynamic range and RSD were 5.0 × 10-10.0 mg L and 1.62% (n = 3), respectively. A limit of detection of 1.0 × 10 mg L sunitinib was obtained from this method. The obtained results showed successful application of the method for the analysis of sunitinib in real samples.
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http://dx.doi.org/10.1016/j.talanta.2020.121190DOI Listing
October 2020

Well-Orientation Strategy for Direct Immobilization of Antibodies: Development of the Immunosensor Using the Boronic Acid-Modified Magnetic Graphene Nanoribbons for Ultrasensitive Detection of Lymphoma Cancer Cells.

Anal Chem 2020 08 4;92(16):11405-11412. Epub 2020 Aug 4.

Chemical Injuries Research Center, Systems Biology and Poisonings Institute, Baqiyatallah University of Medical Sciences, Tehran, Iran.

This work presents an effective strategy for the well-oriented immobilization of antibodies in which boronic acid is directly attached to the surface and with no need of the long and flexible spacer. A magnetic graphene nanoribbon-boronic-acid-based immunosensor was developed and tested for the impedimetric detection of lymphoma cancer cells, a blood cancer biomarker. Magnetic graphene nanoribbons (MGNRs) were modified with boronic acid (BA) to create a supporting matrix that is utilized by immobilizing anti-CD20 antibodies with good orientation. The prepared biosensing layer (MGNR/BA/Ab) with well-oriented antibodies was premixed into whole blood samples to interact with lymphoma cancer cell receptors. In the presence of target cell receptors, an immunocomplex was formed between anti-CD20 antibodies and lymphoma cancer cell receptors. Then, the biosensing layer was magnetically collected on a screen-printed carbon electrode (SPCE) and placed in a homemade electrochemical cell configuration to measure impedimetric signals. The fabrication steps of the immunosensor were characterized by various techniques, such as resonance light scattering, fluorescence, electrochemical impedance spectroscopy, and cyclic voltammetry. The assay is highly sensitive: the calculated limit of detection of lymphoma cancer cells was as low as 38 cells/mL, and the detection was linear from 100 to 1 000 000 cells/mL. The specificity of the immunosensor is also very high, and there is no interference effect with several potential interferents, such as the breast cancer (MCF-7), human embryonic kidney (HEK293), and leukemia (HL-60 and KCL-22) cell lines. The performance of the immunosensor for lymphoma cancer cells in clinical blood samples is consistent with that of commercial flow cytometric assays.
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http://dx.doi.org/10.1021/acs.analchem.0c02357DOI Listing
August 2020

Ratiometric bioassay and visualization of dopamine β-hydroxylase in brain cells utilizing a nanohybrid fluorescence probe.

Anal Chim Acta 2020 Apr 29;1105:187-196. Epub 2020 Jan 29.

Department of Biotechnology, Bu-Ali Sina University, Hamedan, Iran.

Dopamine β-hydroxylase (DBH) is involved in various neuronal transmission processes in the brain. Due to the severe diseases caused by abnormity levels of such important enzyme in human serum, sensitive and rapid detection of DBH at early stages is crucial, particularly for clinical analysis. Herein, we developed optical sensors for DBH that include the following: (i) a ratiometric fluorescence sensor that hybridizes the bovine serum albumin (BSA)-gold nanoclusters (BSA-AuNCs) and nitrogen doped carbon dots (N-CDs). The sensor proved to be highly selective and sensitive, achieving a linear range of 0.02-0.16 μg mL and a limit of detection of 4.0 ng mL. In the presence of DBH, the fluorescence intensity of BSA-AuNCs (λ = 615 nm) was remarkably quenched by DBH serving as a reporter signal, whereas the N-CDs fluorescence intensity at 440 nm was almost kept unchanged serving as a reference signal. The developed ratiometric sensor is capable of demonstrating a color change from pink to violet and blue with a gradual increase in DBH concentration, which is discernible by the naked-eye. A test strip is prepared for semi-quantitative assay and convenient use. Intriguingly, by taking advantage of the inter-AuNCs aggregation in the presence of DBH, (ii) a resonance light scattering (RLS) sensor was also developed based on the nanohybrid probe (detection limit 95 ng mL). Fluorescence imaging in PC12 cell lines demonstrated that the BSA-AuNCs could be utilized in visualization assay towards intracellular DBH. Additionally, the sensors were tested in a real matrix by spiking serum samples with satisfactory recoveries.
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http://dx.doi.org/10.1016/j.aca.2020.01.046DOI Listing
April 2020

Lab in a Tube: Point-of-Care Detection of .

Anal Chem 2020 03 28;92(6):4209-4216. Epub 2020 Feb 28.

Nanobioelectronics & Biosensors Group, Catalan Institute of Nanoscience and Nanotechnology (ICN2), CSIC and BIST, Campus UAB, Bellaterra, Barcelona 08193 Spain.

Significant levels of infectious diseases caused by pathogenic bacteria are nowadays a worldwide matter, carrying considerable public health care challenges and huge economic concerns. Because of the rapid transmission of these biothreat agents and the outbreak of diseases, a rapid detection of pathogens in early stages is crucial, particularly in low-resources settings. To this aim, we developed for the first time a new sensing approach carried out in a single step for O157:H7 detection. The detection principle is based on Förster resonance energy transfer using gold nanoclusters as a signal reporter and gold nanoparticles conjugated with antibodies as a quencher. The sensing platform includes an ultraviolet-light-emitting diode to provide the proper excitation and consists of a microtube containing two pieces of fiber glass; one of them is embedded with label-free gold nanoclusters and the other one with gold nanoparticles conjugated with antibodies. Upon the addition of the sample containing bacteria, the florescence of gold nanoclusters is recovered. The assay was evaluated by the naked eye (on/off) and quantitatively with use of a smartphone camera. The biosensor proved to be highly specific and sensitive, achieving a limit of detection as low as 4.0 cfu mL. Additionally, recoveries of 110% and 95% were obtained when the platforms in spiked river and tap water, respectively, were evaluated.
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http://dx.doi.org/10.1021/acs.analchem.9b04369DOI Listing
March 2020

Magnetic molecularly imprinted electrospun nanofibers for selective extraction of nilotinib from human serum.

Anal Bioanal Chem 2020 Mar 21;412(7):1629-1637. Epub 2020 Jan 21.

Faculty of Chemistry, Bu-Ali Sina University, Fahmideh Av., Hamedan, 65174, Iran.

A new magnetic molecularly imprinted nanofiber (MMIN) nanocomposite was prepared and used to the selective extraction of nilotinib. MMIN was constructed using a novel and general method including a combination of molecular imprinting and electrospinning technology. By electrospun precursor nanofibers containing polyacrylonitrile, FeO magnetic nanoparticles, and nilotinib as the template, molecularly imprinted nanofibers were produced with a mean diameter of 500 nm and lengths up to several millimeters. The microstructure and morphology of the prepared MMIN were thoroughly investigated using techniques such as X-ray diffraction (XRD) and scanning electron microscopy (SEM). The MMIN was then used to the extraction of nilotinib. The extracted nilotinib was re-extracted and determined spectrofluorimetrically at the excitation and emission wavelengths of 271 and 335 nm, respectively. The relation between fluorescence signal for the re-extracted solution and nilotinib concentration was linear in the range 0.01-10.0 mg L (n = 9) and the RSD for the determination of 1.0 and 5.0 mg L nilotinib 2.75% and 1.09% (n = 3), respectively. The detection limit of the method was obtained as 0.002 mg L nilotinib. The results indicated that the proposed method can be successfully applied to the determination of nilotinib in human serum samples. Graphical abstract.
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http://dx.doi.org/10.1007/s00216-020-02393-2DOI Listing
March 2020

In Situ Growth of Metal-Organic Framework HKUST-1 on Graphene Oxide Nanoribbons with High Electrochemical Sensing Performance in Imatinib Determination.

ACS Appl Mater Interfaces 2020 Jan 16;12(4):4859-4869. Epub 2020 Jan 16.

Faculty of Chemistry , Bu-Ali Sina University , Hamedan 6517838695 , Iran.

Metal-organic frameworks (MOFs) have been previously investigated as electrode materials for developing electrochemical sensors. They have usually been reported to suffer from poor conductivity and improvement in the conductivity of MOFs is still a great challenge. Here, we reported the fabrication of an electrochemical sensor based on the in situ growth of framework HKUST-1 on conductive graphene oxide nanoribbons (GONRs)-modified glassy carbon electrode (GCE) (HKUST-1/GONRs/GCE). The as-fabricated modified electrode was characterized using field emission scanning electron microscopy, transmission electron microscopy (TEM), high-resolution TEM, Fourier transform infrared, X-ray diffraction, electrochemical impedance spectroscopy, cyclic voltammetry, and Raman spectroscopy. The voltammetric response of HKUST-1/GONRs/GCE toward Imatinib (IMA), as an anticancer drug, is dramatically higher than HKUST-1/GCE because of the synergic effect of the GONRs and HKUST-1 framework. The calibration curve at the HKUST-1/GONRs/GCE for IMA covered two linear dynamic ranges, 0.04-1.0 and 1.0-80 μmol L, with a detection limit of 0.006 μmol L (6 nmol L). Taking advantage of the conductivity of GONRs and large surface area of HKUST-1, a sensitive modified electrode was developed for the electrochemical determination of IMA. The present method provides an effective strategy to solve the poor conductivity of the MOFs. Finally, the obtained electrochemical performance made this modified electrode promising in the determination of IMA in urine and serum samples.
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http://dx.doi.org/10.1021/acsami.9b18097DOI Listing
January 2020

Electrochemical biosensors for the detection of lung cancer biomarkers: A review.

Talanta 2020 Jan 10;206:120251. Epub 2019 Aug 10.

Chemical Injuries Research Center, Systems Biology and Poisonings Institute, Baqiyatallah University of Medical Sciences, Tehran, Iran. Electronic address:

Cancer is one of the most widespread challenges and important diseases, which has the highest mortality rate. Lung cancer is the most common type of cancer, so that about 25% of all cancer deaths are related to the lung cancer. The lung cancer is classified as two different types with different treatment methodology: the small cell lung carcinoma and nonsmall cell lung carcinoma are two categories of the lung cancer. Since the lung cancer is often in the latent period in its early stages, therefore, early diagnosis of lung cancer has many challenges. Hence, there is a need for sensitive and reliable tools for preclinical diagnosis of lung cancer. Therefore, many detection methods have been employed for early detection of lung cancer. As lung cancer tumors growth in the body, the cancerous cells release numerous DNA, proteins, and metabolites as special biomarkers of the lung cancer. The levels of these biomarkers show the stages of the lung cancer. Therefore, detection of the biomarkers can be used for screening and clinical diagnosis of the lung cancer. There are numerous biomarkers for the lung cancer such as EGFR, CEA, CYFRA 21-1, ENO1, NSE, CA 19-9, CA 125 and VEGF. Nowadays, electrochemical methods are very attractive and useful in the lung cancer detections. So, in this paper, the recent advances and improvements (2010-2018) in the electrochemical detection of the lung cancer biomarkers have been reviewed.
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http://dx.doi.org/10.1016/j.talanta.2019.120251DOI Listing
January 2020

High-performance electrochemical enzyme sensor for organophosphate pesticide detection using modified metal-organic framework sensing platforms.

Bioelectrochemistry 2019 Dec 9;130:107348. Epub 2019 Aug 9.

Chemical Injuries Research Center, Systems Biology and Poisonings Institute, Baqiyatallah University of Medical Sciences, Tehran, Iran. Electronic address:

A practical electrochemical biosensor with high sensitivity was developed for detecting organophosphorus (OP). Initially, Ce metal was introduced into an UiO-66-template to form Ce/UiO-66. Later, graphene oxide (GO), carbon black (CB) and multi-walled carbon nanotubes (MWCNTs) were separately added to Ce/UiO-66 to compare the effect of different carbon-based material types on the performance of the biosensor. Exclusively, Ce/UiO-66/MWCNTs with a Ce (7%) and MWCNT (30%) matrix was found to not only load more acetylcholinesterase (AChE) onto vacant sites but also increase electron transfer and decrease the number of diffusion pathways between the thiocholine and electrode surface. Moreover, the appropriate oxophilicity of Ce coupled with the high surface area and good conductivity of MWCNTs in the UiO-66 structure revealed a high affinity to acetylthiocholine chloride (ATCl) and possible catalysis of the hydrolysis of ATCl with a Michaelis-Menten constant of 0.258 mM. This biosensor, under optimal conditions, demonstrated a rapid and sensitive detection of paraoxon over a wide linear range of 0.01-150 nM, with a low detection limit of 0.004 nM. As a result, the AChE/Ce/UiO-66/MWCNTs/GCE biosensor can be employed in laboratory and field experiments to determine paraoxon levels.
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http://dx.doi.org/10.1016/j.bioelechem.2019.107348DOI Listing
December 2019

Development of Membrane Hollow Fiber for Determination of Maleic Anhydride in Ambient Air as a Field Sampler.

Ann Work Expo Health 2019 08;63(7):797-805

Department of Biostatistics, School of Public Health, Hamadan University of Medical Sciences, Hamadan, Iran.

This research develops a rapid method for sampling and analysis of maleic anhydride (MA) in air using a one-step hollow fiber (HF) membrane in the liquid phase followed by high-performance liquid chromatography. A sampling chamber was prepared for sampling of MA with HF-supported de-ionized water absorbency. Several important parameters, such as sampling flow rate, sampling time, and breakthrough volume (BTV), were optimized at different concentrations using a central composite design. The results showed that sampling could be performed at the maximum period of 4 h with a flow rate of 1 mL min-1 for different concentrations (in the range of 0.05-2 mg m-3). The BTV was 240 mL. The relative standard deviations for the repeatability of interday and intraday were 7-10%, 10%, respectively, and the pooled standard deviation was 0.088. The limit of detection and limit of quantitation values were 0.033 and 0.060 mg m-3, respectively. Moreover, our findings revealed that the samples could be stored in sealed HF flexible plastic tubes in a cover at refrigerator temperature (4°C) for up to 7 days. The HF method was compared with method number 3512 National Institute Occupational Safety and Health for determination of MA. There was a good correlation (R2 = 0.99) between the two methods at a concentration of 0.05 to 2 mg m-3 in the laboratory and the average concentration of MA for both methods was 0.11 mg m-3 in the ambient air at an adhesive manufacturer. Our findings indicated that the proposed HF can act as a reliable, rapid, and effective approach for sampling of MA in workplaces.
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http://dx.doi.org/10.1093/annweh/wxz052DOI Listing
August 2019

Betulin and its derivatives as novel compounds with different pharmacological effects.

Biotechnol Adv 2020 Jan - Feb;38:107409. Epub 2019 Jun 18.

Department of Human Anatomy and Cell Science, Rady College of Medicine, Max Rady Faculty of Health Sciences, University of Manitoba, Winnipeg, Canada; Biology of Breathing Theme, Children Hospital Research Institute of Manitoba, University of Manitoba, Winnipeg, Canada; Health Policy Research Center, Institute of Health, Shiraz University of Medical Sciences, Shiraz, Iran; Research Institute of Oncology and Hematology, CancerCare Manitoba, University of Manitoba, Winnipeg, Canada. Electronic address:

Betulin (B) and Betulinic acid (BA) are natural pentacyclic lupane-structure triterpenoids which possess a wide range of pharmacological activities. Recent evidence indicates that B and BA have several properties useful for the treatment of metabolic disorders, infectious diseases, cardiovascular disorders, and neurological disorders. In the current review, we discuss B and BA structures and derivatives and then comprehensively explain their pharmacological effects in relation to various diseases. We also explain antiviral, antibacterial and anti-cancer effects of B and BA. Finally, we discuss the delivery methods, in which these compounds most effectively target different systems.
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http://dx.doi.org/10.1016/j.biotechadv.2019.06.008DOI Listing
February 2020

Colorimetric immunosensor for determination of prostate specific antigen using surface plasmon resonance band of colloidal triangular shape gold nanoparticles.

Spectrochim Acta A Mol Biomol Spectrosc 2019 Nov 29;222:117218. Epub 2019 May 29.

Chemical Injuries Research Center, Systems Biology and Poisonings Institute, Baqiyatallah University of Medical Sciences, Tehran, Iran. Electronic address:

In this work, we demonstrated the development of a colorimetric immunosensor using surface plasmon resonance band of gold nanoparticles for the detection of prostate specific antigen (PSA). To develop this biosensing tool, triangular gold nanoparticles (AuNPs) were synthesized using Tween-20 as a nonionic surfactant and then, conjugated with PSA capture antibody (Ab-AuNPs). When exposed to Ab-AuNPs, PSA antigens were found to be successfully captured by nanosystem (PSA)-Ab-AuNPs. Next, (PSA)-Ab-AuNPs were incubated with second PSA antibody (2)-decorated magnetite (FeO-Ab) and separated by an external magnetic force to leave Ab-AuNPs in the supernatant solution to be directly analyzed using UV-Vis spectroscopy. It was found that the absorption intensity was directly proportional to the PSA concentration. As a result, the linear range for PSA detection was found to be 0.01-20 ng mL with a detection limit of 0.009 ng mL. Because of significant stability of the prepared Ab-AuNPs and excellent selectivity to the PSA antigen, this simple and sensitive sensing system is proposed to be potentially effective in the fast and real-time analysis of clinical samples from prostate cancer patients. We believe that the simple platform of this immunosensor to be useful in the development of future point-of-care sensing tools, working on the quantification of biomarkers in a drop of blood.
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http://dx.doi.org/10.1016/j.saa.2019.117218DOI Listing
November 2019

Dual-modality impedimetric immunosensor for early detection of prostate-specific antigen and myoglobin markers based on antibody-molecularly imprinted polymer.

Talanta 2019 Sep 27;202:111-122. Epub 2019 Apr 27.

Faculty of Chemistry, Bu-Ali Sina University, Hamedan, Iran.

A new dual-modality immunosensor based on molecularly imprinted polymer (MIP) and a nanostructured biosensing layer has fabricated for the simultaneous detection of two important markers including prostate-specific antigen (PSA) and myoglobin (Myo) in human serum and urine samples. In the first step, 3,3'-dithiodipropionic acid di(N-hydroxysuccinimide ester) (DSP) was self-assembled on a gold screen printed electrode (SPE). Then, the target proteins were attached covalently to the DSP-SPE. The imprinted cocktail polymer ((MIP(PSA, Myo)-SPE)) was synthesized at the SPE surface using acrylamide as monomer, N,N'-methylenebisacrylamide as a crosslinker, and PSA and Myo as the templates, respectively. The MIP-SPE was specific for the impedimetric sensing of PSA and Myo. After that, a nanocomposite (NCP) was synthesized based on the decorated magnetite nanoparticles with multi-walled carbon nanotube, graphene oxide and specific antibody for PSA (Ab). Then, NCP incubated with (MIP(PSA, Myo)-SPE. The modified electrodes and synthesized nanoparticles were characterized using electrochemical impedance spectroscopy, dynamic light scattering, surface plasmon resonance and scanning electron microscopy. The limits of detections were found to be 5.4 pg mL and 0.83 ng mL with the linear dynamic ranges of 0.01-100 and 1-20000 ng mL for PSA and Myo, respectively. The ability of proposed biosensor to detect PSA and Myo simultaneously with high sensitivity and specificity offers a powerful opportunity for the new generation of biosensors. This dual-analyte specific receptors-based device is highly desired for the integration with lab-on-chip kits to measure a wide panel of biomarkers present at ultralow levels during early stages of diseases progress.
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http://dx.doi.org/10.1016/j.talanta.2019.04.061DOI Listing
September 2019

Reduced graphene oxide decorated on Cu/CuO-Ag nanocomposite as a high-performance material for the construction of a non-enzymatic sensor: Application to the determination of carbaryl and fenamiphos pesticides.

Mater Sci Eng C Mater Biol Appl 2019 Sep 7;102:764-772. Epub 2019 May 7.

Chemical Injuries Research Center, Systems Biology and Poisonings Institute, Baqiyatallah University of Medical Sciences, Tehran, Iran. Electronic address:

A novel electrochemical sensor based on the reduced graphene oxide-Cu/CuO-Ag nanocomposite modified glassy carbon electrode (rGO/Cu/CuO-Ag/GCE) has been applied for the simultaneous analysis of carbaryl and fenamiphos as two important pesticides. The electrochemical behavior of carbaryl and fenamiphos at rGO/Cu/CuO-Ag/GCE was studied by cyclic voltammetry and differential pulse voltammetry. The modified electrode exhibited two separated oxidation signals for the simultaneous determination of both carbaryl and fenamiphos with excellent sensitivity. The characteristics of the modified electrode were studied with transmission electron microscopy, X-ray diffraction and Fourier transform-infrared spectroscopy techniques. Under optimized conditions, the rGO/Cu/CuO-Ag/GCE detected carbaryl and fenamiphos with the wide linear ranges of 0.05-20 and 0.01-30 μM, and the detection limits were 0.005 and 0.003 μM, respectively. This developed electrochemical platform applied as a simple and cost-effective sensor for the detection of low levels of carbaryl and fenamiphos in fruit and vegetable samples successfully.
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http://dx.doi.org/10.1016/j.msec.2019.05.010DOI Listing
September 2019
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