Publications by authors named "Mohammad Reza Ganjali"

240 Publications

Fracture fingerprint of polycrystalline CN nanosheets: Theoretical basis.

J Mol Graph Model 2021 Jul 21;106:107899. Epub 2021 Mar 21.

Center of Excellence in Electrochemistry, School of Chemistry, College of Science, University of Tehran, Tehran, Iran. Electronic address:

Polycrystalline carbon nanosheets are composed of several randomly rotated monocrystalline regions facing each other in grain boundaries-the cause of stress concentration-that affects the mechanics of 2D carbon nanostructures. They have been widely used in different fields, particularly in electronic devices. Herein, heterogeneous graphitic carbon nitride (CN) was considered as typical of polycrystalline carbon nanosheets for modelling its fracture behavior. The number of grains with random configuration, temperature, and crack length were systematically changed to track the mode and the intensity of failure of model nanosheets. Molecular dynamics simulations predictions unraveled the interatomic interaction in the C-C and C-N bonds. An increase in the number of grain boundaries from 3 to 25 as well as the length of crack led to more than 70% fall in the Young's modulus of polycrystalline carbon platelets. Stress intensity factor decreased against temperature, but increased by crack length enlargement demonstrating higher fracture toughness of small cracks. This theoretical approach can be generalized to capture the unique fracture fingerprint of polycrystalline carbon structures of different types.
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http://dx.doi.org/10.1016/j.jmgm.2021.107899DOI Listing
July 2021

UV and visible-assisted photocatalytic degradation of pharmaceutical pollutants in the presence of rational designed biogenic FeO-Au nanocomposite.

Environ Sci Pollut Res Int 2021 Feb 27. Epub 2021 Feb 27.

Endocrinology and Metabolism Research Center, Endocrinology and Metabolism Clinical Sciences Institute, Tehran University of Medical Sciences, Tehran, 1411713137, Iran.

In this study, we designed FeO nanoparticles and heterogeneous FeO-Au nanocomposites with a mean size of 21 and 27 nm that synthesized by Foeniculum vulgare seed extract to photodegrade organic micropollutants under UV and visible light irradiation. The physiochemical characteristics of biogenic nanoparticles/nanocomposite are described by XRD, FTIR, UV-Vis, SEM, EDX, and X-ray elemental mapping. In the presence of nanoparticles and nanocomposites under UV irradiation, the total degradation of contaminants is about 85-90% after 2100 s, while under visible light irradiation, degradation efficiencies are about 70-85% after 4800-s irradiation. Total organic carbon analysis results confirmed photodegradation efficacies. Also, the scavenger's experiments show that hydroxyl radical is the most important specie in the degradation of pollutant model. It can be concluded clearly that FeO green nanoparticles and FeO-Au green nanocomposite are very simple and effective photocatalyst for degradation of organic pollutants in very short time under illumination.
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http://dx.doi.org/10.1007/s11356-021-12932-8DOI Listing
February 2021

Detection of tartrazine in fake saffron containing products by a sensitive optical nanosensor.

Food Chem 2021 Jul 5;350:129197. Epub 2021 Feb 5.

Analytical Chemistry Department, Center of Excellence in Electrochemistry, School of Chemistry, College of Science, University of Tehran, Tehran, Iran; Biosensor Research Center, Endocrinology & Metabolism Molecular-Cellular Sciences Institute, Tehran University of Medical Sciences, Tehran, Iran.

A fluorescent assay for the selective analysis of tartrazine was developed. Tartrazine is a health-threatening food additive commonly used as fake saffron. An optical nanosensor was fabricated based on molecular imprinting technique in which carbon dots (CDs) as fluorophores and tartrazine as a template molecule were embedded in molecularly imprinted polymer (MIP) matrix. The synthesized CDs embedded in MIP (CDs-MIP) was characterized by various methods. The fluorescence intensity of (CDs-MIP) was selectively quenched in the presence of tartrazine in comparison with other similar food color additives. The correlation between the quenching of CD-MIP and the concentration of tartrazine was used as an optical sensing for rapid detection of tartrazine in the range of 3.3-20.0 nM (1.8-10.7 μg L) with detection limit of 1.3 nM (0.70 μg L). Eventually, the designed nanosensor was successfully applied for tartrazine detection in foodstuffs such as fake saffron, saffron tea and saffron ice cream samples.
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http://dx.doi.org/10.1016/j.foodchem.2021.129197DOI Listing
July 2021

Electrocatalytic hydrogen evolution on the noble metal-free MoS/carbon nanotube heterostructure: a theoretical study.

Sci Rep 2021 Feb 17;11(1):3958. Epub 2021 Feb 17.

CNRS, IJL, Université de Lorraine, 88000, Épinal, France.

Molybdenum disulfide (MoS) is considered as a promising noble-metal-free electrocatalyst for the Hydrogen Evolution Reaction (HER). However, to effectively employ such material in the HER process, the corresponding electrocatalytic activity should be comparable or even higher than that of Pt-based materials. Thus, efforts in structural design of MoS electrocatalyst should be taken to enhance the respective physico-chemical properties, particularly, the electronic properties. Indeed, no report has yet appeared about the possibility of an HER electrocatalytic association between the MoS and carbon nanotubes (CNT). Hence, this paper investigates the synergistic electrocatalytic activity of MoS/ CNT heterostructure for HER by Density Functional Theory simulations. The characteristics of the heterostructure, including density of states, binding energies, charge transfer, bandgap structure and minimum-energy path for the HER process were discussed. It was found that regardless of its configuration, CNT is bound to MoS with an atomic interlayer gap of 3.37 Å and binding energy of 0.467 eV per carbon atom, suggesting a weak interaction between CNT and MoS. In addition, the energy barrier of HER process was calculated lower in MoS/CNT, 0.024 eV, than in the MoS monolayer, 0.067 eV. Thus, the study elaborately predicts that the proposed heterostructure improves the intrinsic electrocatalytic activity of MoS.
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http://dx.doi.org/10.1038/s41598-021-83562-wDOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7889931PMC
February 2021

Determination of arsenic species using functionalized ionic liquid by in situ dispersive liquid-liquid microextraction followed by atomic absorption spectrometry.

Food Chem 2021 Jul 14;349:129115. Epub 2021 Jan 14.

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

Synthesis and application of a task-specific ionic liquids (TSILs) as extracting solvents or chelating agents in dispersive liquid-liquid micro-extraction (DLLME) was evaluated. The developed method was based on the use of an ammonium pyrrolidine dithiocarbamate (APDC) bonded ionic liquid for chelation with As(III), followed by conversion of the As(III) chelated TSIL to a hydrophobic ionic liquid using KPF as an anion-exchange reagent. As(V) was reduced to As(III), using a 2/1 w/w blend of KI and NaSO and then the total amount of As was measured through ETAAS analysis. Under optimal conditions, linear dynamic ranges of 0.2-15 ng mL and 0.2-20 ng mL were observed in the determination of As(III) and total As respectively. The relative standard deviations (RSD%, n = 5) for the determination of As(III) (10 ng mL) was 3.2% and the limits of detection and quantitation were determined to be 0.01 ng mL and 0.0.034 ng mL; respectively.
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http://dx.doi.org/10.1016/j.foodchem.2021.129115DOI Listing
July 2021

Atomic simulation of adsorption of SO pollutant by metal (Zn, Be)-oxide and Ni-decorated graphene: a first-principles study.

J Mol Model 2021 Feb 4;27(3):70. Epub 2021 Feb 4.

Center of Excellence in Electrochemistry, School of Chemistry, College of Science, University of Tehran, Tehran, Iran.

Due to the impact of toxic gases on human health, considerable interest has been shown in detecting noxious air pollutants, particularly sulfur dioxide (SO), both experimentally and theoretically. This work provides new insights into the adsorbing (SO) molecules on the surface of metal-oxide graphitic structures, i.e., Beryllium-Oxide (BeO), Zinc-Oxide (ZnO), and Ni-decorated graphene applying a first-principles study. Computational analyses suggest that the type of binding of SO molecule on BeO and ZnO sheets is physisorption so that binding energies of -0.405 and -0.154 eV were assigned to ZnO and BeO nanosheets in that order. The adsorption energy of SO on metal oxide sheets was much higher than the pristine graphene. Taking pristine graphene as an adsorbent for SO molecule, it was found that such nanomaterial is not an efficient adsorbent due to the weak interactions (-0.157 eV) and low electron charge transfer (0.042 e) present in SO/graphene complex. To overcome this issue, graphene nanosheets decorated with nickel atoms were studied for interaction with SO2 molecules; the results indicate that the SO molecules were chemisorbed on Ni-decorated graphene sheets with an adsorption energy of -2.297 eV. Chemisorption of SO molecules on Ni-decorated graphene sheets was proven by the strong orbital hybridization between Ni 3d and sulfur 3p orbitals in the Projected Density of States (PDOS) plot. This work provides useful information about SO adsorption on Ni-decorated graphene sheets in order to develop a new class of gas sensing devices. Superior chemisorption of SO on Ni-decorated graphene sheets compared to the physical adsorption on BeO and ZnO sheets makes Ni-decorated graphene a potential candidate for detecting SO molecules.
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http://dx.doi.org/10.1007/s00894-021-04691-7DOI Listing
February 2021

New Water Oxidation Electrocatalyst Based on the Cobalt-Containing Polyoxometalate-Reduced Graphene Oxide Hybrid Nanomaterial.

Langmuir 2021 Feb 29;37(5):1925-1931. Epub 2021 Jan 29.

Center of Excellence in Electrochemistry, School of Chemistry, College of Science, University of Tehran, P.O. Box 14155-6455, Tehran 1417466191, Iran.

A new hybrid nanomaterial based on the immobilization of cobalt-containing polyoxometalate (CoPOM) on the surface of reduced graphene oxide (rGO) was designed for an efficient electrocatalytic water splitting reaction. First, the surface of rGO was functionalized with aminopropylsilyl groups and protonated with hydrochloric acid to produce ammonium groups. Then, the electrostatic interaction of positively charged rGO-supported ammonium groups with anionic CoPOM produced a CoPOM-APTS-rGO hybrid nanomaterial. The achieved hybrid nanomaterial exhibited a low overpotential of 128 mV versus NHE at a current density of 10 mA cm in the electrocatalytic water oxidation at pH 7. In addition, a fast reaction kinetic with a Tafel slope of 74 mV dec was seen in the presence of the prepared hybrid nanomaterial. Linear sweep voltammetry analysis revealed the long-term stability and activity of CoPOM-APTS-rGO for water oxidation in neutral conditions.
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http://dx.doi.org/10.1021/acs.langmuir.0c03418DOI Listing
February 2021

Bi Metal-Organic Framework (Ce/Ni-BTC) as Heterogeneous Catalyst for the Green Synthesis of Substituted Chromeno[4, 3-b]quinolone under Solvent Free Condition.

Curr Org Synth 2021 Jan 21. Epub 2021 Jan 21.

School of Chemistry, College of Science, University of Tehran, Tehran. Iran.

Aims: Novel bi metal organic framework (b-MOF) is synthesized and used as a heterogeneous catalyst for the synthesis of chromeno[4, 3-b]quinolone derivatives via one pot and solvent free, four-component reaction of dimedone, aromatic aldehydes, 4-hydroxycoumarin and ammonium acetate at 110°C.

Background: b-MOFs can be used as a heterogeneous catalyst in the synthesis of many organic compounds. The active and multi-purpose sites in b-MOFs provide a varied function in their catalytic applications. In this paper, reductive CES method is applied for the synthesis of Ce0.47/Ni0.53-BTC b-MOF. The resulting b-MOF was used as a heterogeneous catalyst for the synthesis of chromeno[4, 3-b]quinolone via one pot and solvent free, four- component reaction of dimedone, aromatic aldehyde, 4-hydroxycoumarin and ammonium acetate at 110 °C.

Method: Ce0.47/Ni0.53-BTC was synthesized in an electrochemical cell composed of a stainless steel foil with size of 5cm×5cm centered between two 5cm×5cm sized graphite plates as the anodes by the cathodic current density of 0.2 A/dm2 and placed in a solution of cerium nitrate (0.3 g), nickel nitrate (0.3 g), H3BTC (0.2 g) and NaNO3 (0.1 g) in ethanol (500 mL). Ce0.47/Ni0.53-BTC (10 mg) was added to a mixture of dimedone (1 mmol), aromatic aldehyde (1 mmol), hydroxycoumarin (1 mmol) and ammonium acetate (1.5 mmol) and stirred at 110 °C under solvent free conditions for 45 min. The reaction evolution was controlled by the TLC (hexane:ethyl acetate, 4:1). Then, boiling ethanol was added to the reaction mixture and stirred at room temperature for 15 min. After the reaction completion, the catalyst was separated by centrifuge. Finally, the reaction mixture was placed in an ice bath, which resulted in white solid product and recrystallized from ethanol to give the pure product.

Result: The b-MOF catalyst showed very good efficiency in the synthesis of the desired compounds and can be easily recovered by centrifuge and reused at least five times without decrease in catalytic activity.

Conclusion: In this report, a novel bi metal-organic framework (Ce0.47/Ni0.53-BTC) is synthesized via cathodic electro- synthesis method. The synthesized b-MOF is fully characterized by several characterization methods. The catalytic activity of Ce0.47/Ni0.53-BTC is investigated in the synthesis of chromeno[4, 3-b]quinolone derivatives via one pot four-component reaction of dimedone, aromatic aldehyde, 4-hydroxycoumarin and ammonium acetate. The reaction optimization results showed that the highest isolated yield was obtained, when the reaction was performed in solvent free conditions at 110 °C. The catalyst showed to be highly efficient in the synthesis of the desired compounds and performing the reaction by various starting materials gave the products in good 3 isolated yields, which proves the generality and the scope of the method. The catalyst could easily be recovered by centrifuge and reused at least five times without decrease in catalytic activity.
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http://dx.doi.org/10.2174/1570179418666210122100240DOI Listing
January 2021

Fluorimetric detection of methylated DNA of Sept9 promoter by silver nanoclusters at intrastrand 6C-loop.

Spectrochim Acta A Mol Biomol Spectrosc 2021 Feb 22;247:119081. Epub 2020 Oct 22.

Department of Nanobiotechnology, Faculty of Biological Sciences, Tarbiat Modares University, Tehran, Iran. Electronic address:

Methylation of DNA at carbon 5 of cytosines is the most common epigenetic modification of human genome. Due to its critical role in many normal cell processes such as growth and development, any aberrant methylation pattern in a particular locus may lead to abnormal functions and diseases such as cancer. Development of methods to detect methylation state of DNA which may eliminate labor-intensive chemical or enzymatic treatments has received considerable attention in recent years. Herein, we report a DNA methylation detection procedure based on fluorescence turn-on strategy. Target sequence was selected from Sept9 promoter region that has been reported as one of the most frequently methylated sites in colorectal cancer. Probe DNA was designed to be complementary to this sequence with an additional six cytosines in the middle to form an internal loop to host silver nanoclusters. The fluorescence intensity of the synthesized silver nanoclusters with the duplexes of probe-non-methylated target was significantly different from that of probe-methylated target. The fluorescence enhanced with increasing the methylated DNA concentration with a linear relation in the range of 1.0 × 10 M to 5.0 × 10 M with the detection limit of 8.2 × 10 M, and quenched with non-methylated ones. The method was very specific in the presence of non-complementary sequences with maximum similarity of 40%. Circular dichroism spectra indicated that silver ions significantly affected the structure of methylated and non-methylated DNA into different extents which could further influence the nanocluster fluorescence. Finally, a method was introduced to meet the concerns in the applicability of the proposed method in real situation.
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http://dx.doi.org/10.1016/j.saa.2020.119081DOI Listing
February 2021

Heterojunction of N/B/RGO and g-CN anchored magnetic [email protected] for promoting UV/Vis-induced photo-catalysis and in vitro toxicity studies.

Environ Sci Pollut Res Int 2021 Mar 29;28(9):11430-11443. Epub 2020 Oct 29.

School of Chemistry, College of Science, University of Tehran, Tehran, Iran.

To promote the low photocatalytic efficiency caused by the recombination of electron/hole pairs and widen the photo-response wavelength window, [email protected]/B/RGO and [email protected] ternary heterojunction nanophotocatalysts were designed and successfully prepared through a sol-gel technique. In comparison to bare ZnFeO and ZnO, the [email protected]/B/RGO and [email protected] ternary products showed highly improved photocatalytic properties in the degradation of methyl orange (MO) under ultra-violet (UV) and visible light irradiation. Various physicochemical properties of the photocatalysts were evaluated through field emission scanning electron microscopy (FESEM), energy-dispersive X-ray (EDX) analysis, X-ray diffraction (XRD), UV-visible diffuse reflectance spectroscopy (DRS), Fourier transform infrared spectroscopy (FT-IR), and vibrating sample magnetometer (VSM) techniques. The observations indicated that the ternary heterojuncted [email protected]/B/RGO absorbs lower energy visible light wavelengths, which is an enhancement in the photocatalytic properties of [email protected] loaded on reduced graphene oxide (RGO) nanosheets and graphite-like carbon nitride (g-CN). This gives the catalyst photo-Fenton degradation properties.
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http://dx.doi.org/10.1007/s11356-020-10572-yDOI Listing
March 2021

High-Performance Voltammetric Aptasensing Platform for Ultrasensitive Detection of Bisphenol A as an Environmental Pollutant.

Front Bioeng Biotechnol 2020 4;8:574846. Epub 2020 Sep 4.

Toxicology and Diseases Group (TDG), Pharmaceutical Sciences Research Center (PSRC), The Institute of Pharmaceutical Sciences (TIPS), and Department of Toxicology and Pharmacology, School of Pharmacy, Tehran University of Medical Sciences, Tehran, Iran.

Bisphenol A (BPA) as a pervasive endocrine-disrupting compound (EDC) has been shown to cause multiple detrimental effects including cardiovascular disorders, pregnancy complications, obesity, glucose metabolism disorders, and reproductive toxicity even at a concentration as low as tolerable daily intake (TDI) (4 μg/kg/day). In the present study, a novel ultra-sensitive, electrochemical aptasensor was designed using a screen-printed carbon electrode (SPCE) modified by gold nanoparticles (Au NPs) conjugated to thiolated aptamers for accurate determination of BPA in biological, industrial and environmental samples. To characterize the electrochemical properties of the aptasensor, cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS) were implemented. Detection of BPA was also performed through differential pulse voltammetry (DPV) in [Fe(CN)] electrolyte solution. Under optimum condition, the present electrochemical aptasensor demonstrated an outstanding linear response in the concentration range of 1 pM to 10 nM with a remarkably low limit of detection of 0.113 pM. Due to the superb affinity between anti-BPA aptamers and BPA molecules, the designed aptasensor did not show any significant interaction with other analytes in real samples. Also, fabricated biosensor remained perfectly stable in long-term storage. The analytical results of the fabricated aptasensor are well compatible with those obtained by the ELISA method, indicating the trustworthiness and reasonable accuracy of the application of aptasensor in real samples. Overall, the proposed aptasensor would be a credible and economical method of precise, reproducible, and highly selective detection of minimum levels of BPA in food containers and clinical samples. This would be a promising strategy to enhance the safety of food products and reduce the risk of BPA daily exposure.
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http://dx.doi.org/10.3389/fbioe.2020.574846DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7498542PMC
September 2020

Hydrogel membranes: A review.

Mater Sci Eng C Mater Biol Appl 2020 Sep 30;114:111023. Epub 2020 Apr 30.

Chemistry Department, Yasouj University, Yasouj 75918-74831, Iran. Electronic address:

Hydrogel membranes (HMs) are defined and applied as hydrated porous media constructed of hydrophilic polymers for a broad range of applications. Fascinating physiochemical properties, unique porous architecture, water-swollen features, biocompatibility, and special water content dependent transport phenomena in semi-permeable HMs make them appealing constructs for various applications from wastewater treatment to biomedical fields. Water absorption, mechanical properties, and viscoelastic features of three-dimensional (3D) HM networks evoke the extracellular matrix (ECM). On the other hand, the porous structure with controlled/uniform pore-size distribution, permeability/selectivity features, and structural/chemical tunability of HMs recall membrane separation processes such as desalination, wastewater treatment, and gas separation. Furthermore, supreme physiochemical stability and high ion conductivity make them promising to be utilised in the structure of accumulators such as batteries and supercapacitors. In this review, after summarising the general concepts and production processes for HMs, a comprehensive overview of their applications in medicine, environmental engineering, sensing usage, and energy storage/conservation is well-featured. The present review concludes with existing restrictions, possible potentials, and future directions of HMs.
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http://dx.doi.org/10.1016/j.msec.2020.111023DOI Listing
September 2020

Rapid photodegradation and detection of zolpidem over β-SnWO and α-SnWO nanoparticles: optimization and mechanism.

Environ Sci Pollut Res Int 2021 Feb 23;28(5):5430-5442. Epub 2020 Sep 23.

Faculty of Chemistry and Chemical Engineering, Malek Ashtar University of Technology, P.O. Box 16765-3454, Tehran, Iran.

We reported the tin (II) tungstate nanoparticles as the photocatalyst and sensor modifier that were synthesized via chemical precipitation reaction and optimized thru the Taguchi design method. The method predicted the best synthesis conditions that led to smaller particles and desired morphologies. Different techniques were used to characterize the chemical structure, morphology, and purity of the nanoparticles. The photocatalytic behavior of different crystalline forms of the SnWO nanoparticles (α and β) was considered by photodegradation of methylene orange and zolpidem under UV light irradiation, while the average size of β-SnWO and α-SnWO nanoparticles prepared in optimum conditions is about 17 nm and 20 nm, respectively. Efficiencies of degradation of methyl orange and zolpidem on β-SnWO, in the presence of UV irradiation, were 93% and 98% and in the presence of α-SnWO were 73% and 82% after 2100 s, respectively. Voltammetric sensing of zolpidem was designed by modification of carbon paste electrode via β-SnWO nanoparticles and investigated for determination of the drug in aqueous solution.
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http://dx.doi.org/10.1007/s11356-020-10820-1DOI Listing
February 2021

Bulk-Surface Modification of Nanoparticles for Developing Highly-Crosslinked Polymer Nanocomposites.

Polymers (Basel) 2020 Aug 13;12(8). Epub 2020 Aug 13.

Center of Excellence in Electrochemistry, School of Chemistry, College of Science, University of Tehran, Tehran 11155-4563, Iran.

Surface modification of nanoparticles with functional molecules has become a routine method to compensate for diffusion-controlled crosslinking of thermoset polymer composites at late stages of crosslinking, while bulk modification has not carefully been discussed. In this work, a highly-crosslinked model polymer nanocomposite based on epoxy and surface-bulk functionalized magnetic nanoparticles (MNPs) was developed. MNPs were synthesized electrochemically, and then polyethylene glycol (PEG) surface-functionalized (PEG-MNPs) and PEG-functionalized cobalt-doped (Co-PEG-MNPs) particles were developed and used in nanocomposite preparation. Various analyses including field-emission scanning electron microscopy, Fourier-transform infrared spectrophotometry (FTIR), thermogravimetric analysis (TGA), X-ray diffraction (XRD) and vibrating sample magnetometry (VSM) were employed in characterization of surface and bulk of PEG-MNPs and Co-PEG-MNPs. Epoxy nanocomposites including the aforementioned MNPs were prepared and analyzed by nonisothermal differential scanning calorimetry (DSC) to study their curing potential in epoxy/amine system. Analyses based on revealed that incorporation of 0.1 wt.% of Co-PEG-MNPs into epoxy led to cure at all heating rates, which uncovered the assistance of bulk modification of nanoparticles to the crosslinking of model epoxy nanocomposites. Isoconversional methods revealed higher activation energy for the completely crosslinked epoxy/Co-PEG-MNPs nanocomposite compared to the neat epoxy. The kinetic model based on isoconversional methods was verified by the experimental rate of cure reaction.
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http://dx.doi.org/10.3390/polym12081820DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7465673PMC
August 2020

Efficient removal of dyes and proteins by nitrogen-doped porous graphene blended polyethersulfone nanocomposite membranes.

Chemosphere 2021 Jan 15;263:127892. Epub 2020 Aug 15.

Department of Environmental Engineering, Mersin University, Mersin, 33343, Turkey.

Nitrogen-doped porous graphene oxide (N-PGO) was synthesized, characterized, and applied as a hydrophilic nanomaterial in fabrication of polyethersulfone (PES) membrane for Reactive Red 195 dye and bovine serum albumin (BSA) protein separation. The N-PGO nanosheets not merely showed a good adhesion towards polymers, but simultaneously promoted hydrogen bonding action. Therefore, high-efficiency permeation passageway in the separation layer of membranes was attained. X-ray photoelectron spectroscopy (XPS), energy dispersive spectroscopy (EDX) and Fourier transform infra-red spectroscopy (FTIR) analyses approved nitrogen doping, which increased hydrophilicity and hydrogen bonding ability of PGO in water filtration. The pure water permeation of nanocomposite membranes could reach as high as 190 L m h at 3 bar. A dye rejection efficiency higher than 92% and BSA rejection higher than 95% were accordingly obtained. Atomic force microscopy (AFM) images approved formation of a rough surface that was decreased by addition of low amounts of the PGO. SEM images provided from the surface also confirmed enlarged pore size and increased porosity. Antifouling properties were investigated by BSA filtration, and results showed that the flux recovery ratio of the N-PGO membrane was improved. Overall, the N-PGO hybrid membranes exhibited potential for application in separation of typical proteins and dyes with good antifouling properties.
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http://dx.doi.org/10.1016/j.chemosphere.2020.127892DOI Listing
January 2021

A Sensitive Aptamer-Based Biosensor for Electrochemical Quantification of PSA as a Specific Diagnostic Marker of Prostate Cancer.

J Pharm Pharm Sci 2020 ;23:243-258

Toxicology and Diseases Group (TDG), Pharmaceutical Sciences Research Center (PSRC), The Institute of Pharmaceutical Sciences (TIPS), and Department of Toxicology and Pharmacology, School of Pharmacy, Tehran University of Medical Sciences, Tehran, Iran. Endocrinology and Metabolism Molecular-Cellular Sciences Institute, Tehran University of Medical Sciences, Tehran, Iran.

Purpose: The current project aimed to design a simple, highly sensitive, and economical label-free electrochemical aptasensor for determination of prostate-specific antigen (PSA), as the gold standard biomarker for prostate cancer diagnosis. The aptasensor was set up using a screen-printed carbon electrode (SPCE) modified by gold nanoparticles (Au NPs) conjugated to thiolated aptamers.

Methods: Cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS) were implemented for electrochemical (EC) characterization of the aptasensor. The determination of PSA was also performed through differential pulse voltammetry (DPV) in [Fe (CN) 6]3-/4- electrolyte solution.

Results: The present aptasensor was shown an outstanding linear response in the concentration range of 1 pg/mL - 200 ng/mL with a remarkably lower limit of detection of 0.077 pg/mL. The optimum concentration for PSA separation and the optimum incubation time for antigen-aptamer binding were determined by observing and electing the highest electrochemical responses in a specified time or concentration.

Conclusion: According to the results of the specificity tests, the designed aptasensor did not show any significant interactions with other analytes in real samples. Clinical functionality of the aptasensor was appraised in serum samples of healthy individuals and patients examining the PSA level through the fabricated aptasensor and the reference methods. Both methods are comparable in sensitivity. The present fabricated PSA aptasensor with substantial characteristics of ultra- sensitivity and cost-effectiveness can be conventionally built and used for the routine check-up of the men for prostate problems.
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http://dx.doi.org/10.18433/jpps31171DOI Listing
January 2020

Zeolites for theranostic applications.

J Mater Chem B 2020 07 30;8(28):5992-6012. Epub 2020 Jun 30.

Center of Excellence in Electrochemistry, School of Chemistry, College of Science, University of Tehran, Tehran, Iran.

Theranostic platforms bring about a revolution in disease management. During recent years, theranostic nanoparticles have been utilized for imaging and therapy simultaneously. Zeolites, because of their porous structure and tunable properties, which can be modified with various materials, can be used as a delivery agent. The porous structure of a zeolite enables it to be loaded and unloaded with various molecules such as therapeutic agents, photosensitizers, biological macromolecules, MRI contrast agents, radiopharmaceuticals, near-infrared (NIR) fluorophores, and microbubbles. Furthermore, theranostic zeolite nanocarriers can be further modified with targeting ligands, which is highly interesting for targeted cancer therapies.
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http://dx.doi.org/10.1039/d0tb00719fDOI Listing
July 2020

Diphenylalanin nanofibers-inspired synthesis of fluorescent gold nanoclusters for screening of anti-amyloid drugs.

Methods Appl Fluoresc 2020 Jul 28;8(4):045002. Epub 2020 Jul 28.

Department of Nanobiotechnology, Faculty of Biological Sciences, Tarbiat Modares University, Tehran, Iran.

Protein misfolding and aggregation into amyloid structures is linked with a number of pathophysiological disorders. In the past decade, significant progresses have been made in the drug discovery strategies against toxic aggregates. Although lack of specificity and high sensitivity for in vitro screening system still seen. Here we demonstrate a new targeting probe based on FF diphenylalanine peptide -protected gold nanoclusters (FF AuNCs). Diphenylalanine peptide has previously been shown to self-assemble into well-ordered fiber like the fibers that are observed in amyloid aggregates. We used of the self-assembly properties along with the ability of FF dipeptide in reduction of gold ions for synthesis of novel Au nanoclusters. We used FF AuNCs for monitoring of effectiveness of anti-amyloid drugs. Fluorescence was considerably diminished when drugs at different concentrations added, due to destruction of the amyloid fibers. Furthermore, the analysis of several components demonstrates significant selectivity against the amyloid disrupting molecules. Prepared FF AuNCs will gain possible strategy for in vitro screening of amyloid disrupting molecules.
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http://dx.doi.org/10.1088/2050-6120/ab9fefDOI Listing
July 2020

Kinetics of Cross-Linking Reaction of Epoxy Resin with Hydroxyapatite-Functionalized Layered Double Hydroxides.

Polymers (Basel) 2020 May 18;12(5). Epub 2020 May 18.

Department of Resin and Additives, Institute for Color Science and Technology, P.O. Box 16765-654, Tehran, Iran.

The cure kinetics analysis of thermoset polymer composites gives useful information about their properties. In this work, two types of layered double hydroxide (LDH) consisting of Mg and Zn as divalent metal ions and CO as an anion intercalating agent were synthesized and functionalized with hydroxyapatite (HA) to make a potential thermal resistant nanocomposite. The curing potential of the synthesized nanoplatelets in the epoxy resin was then studied, both qualitatively and quantitatively, in terms of the as well as using isoconversional methods, working on the basis of nonisothermal differential scanning calorimetry (DSC) data. Fourier transform infrared spectroscopy (FTIR) was used along with X-ray diffraction (XRD) and thermogravimetric analysis (TGA) to characterize the obtained LDH structures. The FTIR band at 3542 cm corresponded to the O-H stretching vibration of the interlayer water molecules, while the weak band observed at 1640 cm was attributed to the bending vibration of the H-O of the interlayer water. The characteristic band of carbonated hydroxyapatite was observed at 1456 cm. In the XRD patterns, the well-defined (00l) reflections, i.e., (003), (006), and (110), supported LDH basal reflections. Nanocomposites prepared at 0.1 wt % were examined for curing potential by the as a qualitative criterion that elucidated a cure state for epoxy/LDH nanocomposites. Moreover, the curing kinetics parameters including the activation energy (), reaction order, and the frequency factor were computed using the and Kissinger-Akahira-Sunose () isoconversional methods. The evolution of confirmed the inhibitory role of the LDH in the crosslinking reactions. The average value of for the neat epoxy was 54.37 kJ/mol based on the method, whereas the average values were 59.94 and 59.05 kJ/mol for the epoxy containing Zn-Al-CO-HA and Mg Zn-Al-CO-HA, respectively. Overall, it was concluded that the developed LDH structures hindered the epoxy curing reactions.
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http://dx.doi.org/10.3390/polym12051157DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7284359PMC
May 2020

Poloxamer: A versatile tri-block copolymer for biomedical applications.

Acta Biomater 2020 07 15;110:37-67. Epub 2020 May 15.

School of Chemical Sciences, M G University, Kottayam 686560, Kerala, India.

Poloxamers, also called Pluronic, belong to a unique class of synthetic tri-block copolymers containing central hydrophobic chains of poly(propylene oxide) sandwiched between two hydrophilic chains of poly(ethylene oxide). Some chemical characteristics of poloxamers such as temperature-dependent self-assembly and thermo-reversible behavior along with biocompatibility and physiochemical properties make poloxamer-based biomaterials promising candidates for biomedical application such as tissue engineering and drug delivery. The microstructure, bioactivity, and mechanical properties of poloxamers can be tailored to mimic the behavior of various types of tissues. Moreover, their amphiphilic nature and the potential to self-assemble into the micelles make them promising drug carriers with the ability to improve the drug availability to make cancer cells more vulnerable to drugs. Poloxamers are also used for the modification of hydrophobic tissue-engineered constructs. This article collects the recent advances in design and application of poloxamer-based biomaterials in tissue engineering, drug/gene delivery, theranostic devices, and bioinks for 3D printing. STATEMENT OF SIGNIFICANCE: Poloxamers, also called Pluronic, belong to a unique class of synthetic tri-block copolymers containing central hydrophobic chains of poly(propylene oxide) sandwiched between two hydrophilic chains of poly(ethylene oxide). The microstructure, bioactivity, and mechanical properties of poloxamers can be tailored to mimic the behavior of various types of tissues. Moreover, their amphiphilic nature and the potential to self-assemble into the micelles make them promising drug carriers with the ability to improve the drug availability to make cancer cells more vulnerable to drugs. However, no reports have systematically reviewed the critical role of poloxamer for biomedical applications. Research on poloxamers is growing today opening new scenarios that expand the potential of these biomaterials from "traditional" treatments to a new era of tissue engineering. To the best of our knowledge, this is the first review article in which such issue is systematically reviewed and critically discussed in the light of the existing literature.
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http://dx.doi.org/10.1016/j.actbio.2020.04.028DOI Listing
July 2020

Effect of Surface Treatment of Halloysite Nanotubes (HNTs) on the Kinetics of Epoxy Resin Cure with Amines.

Polymers (Basel) 2020 Apr 17;12(4). Epub 2020 Apr 17.

Department of Resin and Additives, Institute for Color Science and Technology, Tehran P.O. Box: 16765-654, Iran.

The epoxy/clay nanocomposites have been extensively considered over years because of their low cost and excellent performance. Halloysite nanotubes (HNTs) are unique 1D natural nanofillers with a hollow tubular shape and high aspect ratio. To tackle poor dispersion of the pristine halloysite (P-HNT) in the epoxy matrix, alkali surface-treated HNT (A-HNT) and epoxy silane functionalized HNT (F-HNT) were developed and cured with epoxy resin. Nonisothermal differential scanning calorimetry (DSC) analyses were performed on epoxy nanocomposites containing 0.1 wt.% of P-HNT, A-HNT, and F-HNT. Quantitative analysis of the cure kinetics of epoxy/amine system made by isoconversional Kissinger-Akahira-Sunose () and methods made possible calculation of the activation energy () as a function of conversion (α). The activation energy gradually increased by increasing α due to the diffusion-control mechanism. However, the average value of for nanocomposites was lower comparably, suggesting autocatalytic curing mechanism. Detailed assessment revealed that autocatalytic reaction degree, increased at low heating rate from 0.107 for neat epoxy/amine system to 0.908 and 0.24 for epoxy/P-HNT and epoxy/A-HNT nanocomposites, respectively, whereas epoxy/F-HNT system had value of 0.072 as a signature of dominance of non-catalytic reactions. At high heating rates, a similar behavior but not that significant was observed due to the accelerated gelation in the system. In fact, by the introduction of nanotubes the mobility of curing moieties decreased resulting in some deviation of experimental cure rate values from the predicted values obtained using and methods.
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http://dx.doi.org/10.3390/polym12040930DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7240500PMC
April 2020

An Electrochemical Aptasensor Platform Based on Flower-Like Gold Microstructure-Modified Screen-Printed Carbon Electrode for Detection of Serpin A12 as a Type 2 Diabetes Biomarker.

Int J Nanomedicine 2020 31;15:2219-2230. Epub 2020 Mar 31.

Department of Toxicology and Pharmacology, School of Pharmacy, Tehran University of Medical Sciences, Tehran, Iran.

Purpose: In the present study, a highly sensitive and simple electrochemical (EC) aptasensor for the detection of serpin A12 as a novel biomarker of diabetes was developed on a platform where flower-like gold microstructures (FLGMs) are electrodeposited onto a disposable screen-printed carbon electrode. Meanwhile, serpin A12-specific thiolated aptamer was covalently immobilized on the FLGMs.

Methods: The electrochemical activity of a fabricated aptasensor under various conditions were examined by cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS). Aptamer concentration, deposition time, self-assembly time, and incubation time were optimized for assay of serpin A12. The differential pulse voltammetry (DPV) was implemented for quantitative detection of serpin A12 in K [Fe (CN) ]/K [Fe (CN) ] solution (redox probe).

Results: The label-free aptasensor revealed a linear range of serpin A12 concentration (0.039-10 ng/mL), detection limit of 0.020 ng/mL (S/N=3), and 0.031 ng/mL in solution buffer and plasma, respectively.

Conclusion: The results indicate that this aptasensor has a high sensitivity, selectivity, stability, and acceptable reproducibility for detection of serpin A12 in diabetic patients.
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http://dx.doi.org/10.2147/IJN.S244315DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7127862PMC
July 2020

Zinc solubilization characteristics of efficient siderophore-producing soil bacteria.

Iran J Microbiol 2019 Oct;11(5):419-430

Center of Excellence in Electrochemistry, Faculty of Chemistry, University of Tehran, Tehran, Iran.

Background And Objectives: Iron and zinc are two essential micro-nutrients for plant growth and development. Therefore, isolation of siderophores-producing and zinc-solubilizing rhizobacteria involved in bio-availability of these elements is of great interest.

Materials And Methods: In this study, soil samples collected from slightly alkaline soil types were screened for high levels of siderophore secretion and zinc solubilization.

Results: Among positive colonies, three isolates, named F21A, F37 and F38, were able to secrete siderophore at high levels, ranged between 200 and 300 μM/liter. A close association was observed between siderophore production capability and growth rate as an indicator of active metabolism. Siderophore production was closely correlated with the level of zinc ion released into the medium as well. All three siderophore producing isolates were able to withstand temperature as high as 37°C, high concentration of NaCl (up to 2.5%) and a wide range of initial pH from 6 to 9 while hydrolyzing Zn compounds actively. One of the isolates, F21A, tolerated the presence of 200 mgl of zinc. Biochemical and molecular characteristics are indicative that these isolates are . As experienced in a greenhouse experiment, inoculation with the F21A and F37 isolates significantly increase the plants height, fresh and dry weight of corn with compared to control.

Conclusion: These findings demonstrated that the potential of strains as plants growth promoting rhizobacteria (PGPR) in iron and zinc deficient soils.
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http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7049313PMC
October 2019

Zeolites in drug delivery: Progress, challenges and opportunities.

Drug Discov Today 2020 04 13;25(4):642-656. Epub 2020 Feb 13.

Lunenfeld-Tanenbaum Research Institute, Mount Sinai Hospital, University of Toronto, Toronto, ON, Canada. Electronic address:

There are continuing attempts to achieve appropriate controlled-release therapeutic systems by designing innovative functional drug delivery systems (DDS). Although various types of delivery system have been developed, strategies that have successfully made it to the clinic are rare. Given their diverse structures, zeolites have attracted significant research attention for controlled and targeted drug delivery purposes. The structure of zeolites can be microporous, mesoporous or macroporous, which can be exploited to deliver a variety of therapeutic agents to the target site in a controlled manner. In this review, we introduce the different types of zeolite, and discuss the challenges and opportunities associated with their usage as drug delivery systems.
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http://dx.doi.org/10.1016/j.drudis.2020.02.005DOI Listing
April 2020

From microporous to mesoporous mineral frameworks: An alliance between zeolite and chitosan.

Carbohydr Res 2020 Mar 1;489:107930. Epub 2020 Feb 1.

Center of Excellence in Electrochemistry, School of Chemistry, College of Science, University of Tehran, Tehran, Iran. Electronic address:

Microporous and mesoporous minerals are key elements of advanced technological cycles nowadays. Nature-driven microporous materials are known for biocompatibility and renewability. Zeolite is known as an eminent microporous hydrated aluminosilicate mineral containing alkali metals. It is commercially available as adsorbent and catalyst. However, the large quantity of water uptake occupies active sites of zeolite making it less efficient. The widely-used chitosan polysaccharide has also been used in miscellaneous applications, particularly in medicine. However, inferior mechanical properties hampered its usage. Chitosan-modified zeolite composites exhibit superior properties compared to parent materials for innumerable requests. The alliance between a microporous and a biocompatible material with the accompaniment of negative and positive charges, micro/nanopores and proper mechanical properties proposes promising platforms for different uses. In this review, chitosan-modified zeolite composites and their applications have been overviewed.
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http://dx.doi.org/10.1016/j.carres.2020.107930DOI Listing
March 2020

hsa-miR-766-5p as a new regulator of mitochondrial apoptosis pathway for discriminating of cell death from cardiac differentiation.

Gene 2020 Apr 4;736:144448. Epub 2020 Feb 4.

Department of Biochemistry, Faculty of Biological Sciences, Tarbiat Modares University, Tehran, Iran. Electronic address:

Dispose of unnecessary cells in multicellular organism take place through apoptosis as a mode of programmed cell death (PCD). This process is triggered through two main pathway including extrinsic pathway or death receptor pathway and intrinsic or mitochondrial pathway. An alternative role for mitochondrial pathway of cell death is its involvement in cell differentiation. Biochemistry of cell differentiation indicates a common origin for differentiation and apoptosis. miRNAs are a group of small non coding mediator RNAs in regulation of many routes such as apoptosis and differentiation. By using bioinformatics tools hsa-miR-766-5p was predicted to target the BAX, BAK and BOK genes involved in mitochondrial apoptosis pathway. RT-qPCR and dual luciferase assay showed targeting of BAX, BAK and BOK 3'UTRs via hsa-miR-766, detected in SW480 and HEK293T cell lines. Caspases 3/7 and 9 activity assay revealed the involvement of hsa-miR-766-5p in mitochondrial apoptosis pathway regulation detected following overexpression and downregulation of this miRNA, detected in SW480 cells treated with 1 μM doxorubicin. Flow cytometry and MTT assay indicated cell death reduction and viability elevation effect of hsa-miR-766 in SW480 cells after its overexpression. Endogenous expression of hsa-miR-766 during the course of human embryonic stem cells (hESCs) differentiation into cardiomyocytes revealed an inverse expression status of this miRNA with BOK. However, the expression of this miRNA was inversely related to BAX and BAK for some time points of differentiation. Overall this results show the involvement of hsa-miR-766 in regulation of mitochondrial apoptosis pathway.
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http://dx.doi.org/10.1016/j.gene.2020.144448DOI Listing
April 2020

Tissue engineering with electrospun electro-responsive chitosan-aniline oligomer/polyvinyl alcohol.

Int J Biol Macromol 2020 Mar 3;147:160-169. Epub 2020 Jan 3.

Department of Chemical and Biomolecular Engineering, Korea Advanced Institute of Science and Technology (KAIST), Daejeon, Republic of Korea. Electronic address:

Mimicking the native tissue is an ultimate goal in tissue engineering. In this study, conductive chitosan was synthesized by coupling with aniline oligomers, and then conductive nanofibers were fabricated using electrospinning technique to mimic the tissue structure and properties. The conductivity of the resulting biomaterial was adjusted to ca. 10 S/cm, which can recapitulate electrical properties of the tissue. The structure of nanofiber was evaluated using scanning electron microscopy noticing that the aniline oligomer addition to the system decreased the diameter of the nanofiber because of its hydrophobic nature. Conductive nanofiber exhibited on-demand drug release feature of the conductive webs, signaled by 40% rise in the drug release at 40 min after electrical stimulation in comparison with non-stimulated webs, characteristic of a promising drug release platform. Moreover, biocompatibility evaluation using MTT assay revealed that the conductive substrate provides a higher cellular activity to the platform with respect to non-conductive substrates. Such platforms are the harbingers of the emerging new generation, which can revolutionize the tissue engineering satisfying an enhanced tissue regeneration.
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http://dx.doi.org/10.1016/j.ijbiomac.2019.12.264DOI Listing
March 2020

Facile electrochemical preparation of overoxidizedpolypyrrole/RGO composite for ds-DNA immobilization: a novel signal amplified sensing platform for electrochemical determination of chlorpheniramine.

Daru 2020 Jun 5;28(1):57-64. Epub 2019 Dec 5.

NanoBioElectrochemistry Research Center, Bam University of Medical Sciences, Bam, Iran.

Background: Chlorpheniramine (CPA), thanks to its relatively lower side effects, is a widely prescribed medicine for alleviating allergic symptoms as well as some medical emergencies. Owning to this extensive use, many efforts have been directed to measure chlorpheniramine both in vivo and in vitro. High performance liquid chromatography (HPLC), both normal and reverse phase, as well as spectrochemical and electrochemical methods are analytical approaches which have been extensively exploited for determination of CPA. Among them, electrochemical techniques have found elegant place for analysis of CPA due to simplicity, sensitivity and ease of instrumentation.

Methods: Herein, we have reported the preparation and characterization of a biosensor by immobilization of double-stranded DNA on the surface of overoxidizedpolypyrrole-reduced graphene oxide modified pencil graphite electrode (ds-DNA-PPyox/RGO/PGE) as well as its novel usability in measurement of chlorpheniramine (CPA). Scanning electron microscopy (SEM), electrochemical impedance spectroscopy (EIS), UV-Vis spectroscopy and differential pulse voltammetry (DPV) were exploited in order to characterize and evaluate the performance of the proposed biosensor.

Results: Final results showed that proposed strategy for modification of PGE introduces an ultra-sensitive biosensor for CPA which offers the best detection limitamong all previously reported electrochemical sensors for CPA. Taking advantage of this biosensor for determination of CPA, a wide linear dynamic range from 0.05 to 200 μM, and a low limit of detection 0.023 μM were obtained by using DPV method. Usability of this biosensor was also confirmed by determination of CPA in tablet and spiked urine samples.

Conclusions: Overoxidized polypyrrole-reduced graphene oxide offered a suitable substrate for immobilization of ds-DNA by which a new biosensor for determination of CPA was fabricated. Proposed biosensor can successfully be used for determination of CPA in urine samples taking advantage of electroanalytical methods. Graphical abstract.
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http://dx.doi.org/10.1007/s40199-019-00314-yDOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7214598PMC
June 2020

Paper based colorimetric detection of miRNA-21 using Ag/Pt nanoclusters.

Spectrochim Acta A Mol Biomol Spectrosc 2020 Feb 5;227:117529. Epub 2019 Nov 5.

Center of Excellence in Electrochemistry, School of Chemistry, College of Science, University of Tehran, Tehran, Iran; Biosensor Research Center, Endocrinology and Metabolism Molecular-Cellular Sciences Institute, Tehran University of Medical Sciences, Tehran, Iran.

Abnormal expression of MicroRNA-21 (miRNA-21) is considered to be a reliable biomarker for the early diagnosis of cancer. In this work, a novel paper based biosensor was fabricated to detect sub-micro molar concentrations of miRNA-21 based on peroxidase mimetic activity of DNA-templated Ag/Pt nanoclusters (DNA-Ag/Pt NCs), which could catalyze the reaction of hydrogen peroxide and 3,3',5,5' tetramethylbenzidine (TMB), to produce a blue color. The Mechanism of reaction was based on the inhibition effect of miRNA-21 on peroxidase-like activity of nanosensor which resulted to quantitative determination of miRNA-21 concentration. It was found that miRNA-21 could be linearly detected in the range from 1-700 pM (A = 0.16x-0.96, R = 0.99; x = -log [miRNA-21]) with a detection limit of 0.6 pM. Moreover, a paper assay was carried out on a Y-shaped paper-based microfluidic device in order to use the distinctive features of micro-channels such as short response time, very low reagent volume, low fabrication cost, etc. After performing paper based assay, a good linear range was observed between 10-1000 pM (y = 0.06x+147.48, R = 0.99; x = [miRNA-21]) with detection limit of 4.1 pM. The practical application of proposed method for detection of miRNA-21 in real sample was assayed in the human urine sample and indicated the colorimetric method had acceptable accuracy.
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http://dx.doi.org/10.1016/j.saa.2019.117529DOI Listing
February 2020

Electrochemical determination of the antipsychotic medication clozapine by a carbon paste electrode modified with a nanostructure prepared from titania nanoparticles and copper oxide.

Mikrochim Acta 2019 10 15;186(11):698. Epub 2019 Oct 15.

Physiology Research Center, Iran University of Medical Sciences, Tehran, 14496-14535, Iran.

A nanostructure was prepared from titania nanoparticles and copper oxide ([email protected]) and used to modify a carbon paste electrode (CPE). The modified CPE is shown to enable sensitive voltammetric determination of the drug clozapine (CLZ). The sensor was characterized by various techniques and some key parameters were optimized. Under the optimum conditions and at a working potential of 0.6 V (vs. Ag/AgCl), the modified CPE has two linear response ranges, one from 30 pmol L to 4 nmol L of CLZ, the other from 4 nmol L to 10 μmol L. The detection limit is as low as 9 pM. The transfer coefficient (α) and catalytic rate constant (k) were calculated and the reliability of the sensor was estimated for CLZ sensing in real samples where it gave satisfactory results. Graphical abstract Applicability of the [email protected] nanostructures in fabrication of an efficient clozapine (CLZ) sensor based on the use of a carbon paste electrode.
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http://dx.doi.org/10.1007/s00604-019-3760-7DOI Listing
October 2019