Publications by authors named "Hasan Bagheri"

54 Publications

A colorimetric electronic tongue for point-of-care detection of COVID-19 using salivary metabolites.

Talanta 2022 Aug 14;246:123537. Epub 2022 May 14.

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

The monitoring of profile concentrations of chemical markers in saliva samples can be used to diagnose COVID-19 patients, and differentiate them from healthy individuals. Here, this purpose is achieved by designing a paper-based colorimetric sensor with an origami structure, containing general receptors such as pH-sensitive organic dyes, Lewis donors or acceptors, functionalized nanoparticles, and ion metal complexes. The color changes taking place in the receptors in the presence of chemical markers are visually observed and recorded with a digital instrument. Different types and amounts of the chemical markers provide the sensor with a unique response for patients (60 samples) or healthy (55 samples) individuals. These two categories can be discriminated with 84.3% accuracy. This study evidences that the saliva composition of cured and healthy participants is different from each other with accuracy of 85.7%. Moreover, viral load values obtained from the rRT-PCR method can be estimated by the designed sensor. Besides COVID-19, it may possible to simultaneously identify smokers and people with kidney disease and diabetes using the specified electronic tongue. Due to its high efficiency, the prepared paper device can be employed as a rapid detection kit to detect COVID-19.
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http://dx.doi.org/10.1016/j.talanta.2022.123537DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC9107099PMC
August 2022

A ratiometric electrochemical DNA-biosensor for detection of miR-141.

Mikrochim Acta 2022 05 5;189(6):213. Epub 2022 May 5.

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

A sensitive biosensor for the detection of miR-141 has been constructed. The DNA-biosensor is prepared by first immobilizing the thiolated methylene blue-labeled hairpin capture probe (MB-HCP) on two-layer nanocomposite film graphene [email protected] polyvinylpyrrolidone-gold nanourchin modified glassy carbon electrode. We used the hematoxylin as an electrochemical auxiliary indicator in the second stage to recognize DNA hybridization via the square wave voltammetry (SWV) responses that record the accumulated hematoxylin on electrode surfaces. The morphology and chemical composition of nanocomposite was characterized using TEM, FE-SEM, and FT-IR techniques. The preparation stages of the DNA-biosensor were screened by electrochemical impedance spectroscopy and cyclic voltammetry. The proposed DNA-biosensor can distinguish miR-141 from a non-complementary and mismatch sequence. A detection limit of 0.94 fM and a linear range of 2.0 -5.0 × 10 fM were obtained using SWV for miR-141 detection. The working potential for methylene blue and hematoxylin was -0.28 and + 0.15 V vs. Ag/AgCl, respectively. The developed biosensor can be successfully used in the early detection of non-small cell lung cancer (NSCLC) by directly measuring miR-141 in human plasma samples. This novel DNA-biosensor is of promise in early sensitive clinical diagnosis of cancers with miR-141 as its biomarker.
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http://dx.doi.org/10.1007/s00604-022-05301-wDOI Listing
May 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

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

Enzymeless voltammetric sensor for simultaneous determination of parathion and paraoxon based on Nd-based metal-organic framework.

Chemosphere 2022 Apr 29;292:133440. Epub 2021 Dec 29.

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

The aim of this work is to fabricate a sensitive and novel enzymeless electrochemical sensor for the simultaneous determination of parathion and paraoxon using the [email protected] nanocomposite. For this purpose, Neodymium (Nd) was introduced into a Universitetet i Oslo (UiO-66) structure to construct Nd-UiO-66 and then, adding multi-walled carbon nanotubes to the Nd-UiO-66 to increase the electrocatalytic activity and surface area of the obtained composite. The [email protected] has numerous advantages like excellent conductivity, tunable texture, and large surface area and can be used as a distinctive structure for the construction of modified glassy carbon electrode (GCE) to enhance the charge-transfer and the efficiency of electrochemical sensors. This modified electrode showed sensitive and selective determination of paraoxon and parathion over the linear ranges of 0.7-100 and 1-120 nM, with detection limits of 0.04 and 0.07 nM, respectively. The proposed [email protected]/GCE sensor in this study can be applied in environmental and toxicological laboratories and field tests to detect parathion and paraoxon levels.
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http://dx.doi.org/10.1016/j.chemosphere.2021.133440DOI Listing
April 2022

Construction and application of a novel electrochemical sensor for trace determination of uranium based on ion-imprinted polymers modified glassy carbon electrode.

Chemosphere 2022 Apr 25;292:133435. Epub 2021 Dec 25.

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

In the present work, a novel electrochemical sensor modified glassy carbon electrode with ion-imprinted polymers (IIP-GCE) was applied for uranyl ions (UO) determination. Surface modifier was synthesized through precipitation polymerization method, using acrylic acid as a monomer, benzoyl peroxide (BPO) as initiator, and trimethylolpropane triacrylate (TMPTA) as cross-linker. A new uranyl-trans-3-(3-pyridyl) acrylic acid complex was employed, serving as an active and specific site on the synthesized modifier. Next, the synthesized modifier was characterized using X-ray diffraction (XRD), Scanning Electron microscopy (SEM), and Fourier Transform Infrared Spectroscopy (FT-IR) techniques. UO ions were detected using a differential pulse adsorptive anodic stripping voltammetry method. Under the optimized conditions (pH = 8.0, pre-concentration time = 10 min and pre-concentration potential = -0.30 V), the modified electrode exhibited linear behavior in the interval of 1.27-95.49 μg.L with a limit of detection (LOD) of 0.43 μg.L. Also, the constructed ion-imprinted sensor showed a successful application for determining UO ions with recovery range of 97.6-101% in real samples.
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http://dx.doi.org/10.1016/j.chemosphere.2021.133435DOI Listing
April 2022

Dual-template rectangular nanotube molecularly imprinted polypyrrole for label-free impedimetric sensing of AFP and CEA as lung cancer biomarkers.

Talanta 2022 Mar 13;239:123146. Epub 2021 Dec 13.

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

A high-performance sensing layer based on dual-template molecularly imprinted polymer (DMIP) was fabricated and successfully applied for one-by-one detection of carcinoembryonic antigen (CEA) and alpha-fetoprotein (AFP) as lung cancer biomarkers. The plastic antibodies of AFP and CEA were created into the electropolymerized polypyrrole (PPy) on a fluorine-doped tin oxide (FTO) electrode. Raman spectroscopy, field emission scanning electron microscopy (FE-SEM), cyclic voltammetry (CV), and electrochemical impedance spectroscopy (EIS) tests were performed to pursue the formation and characterization of the sensing layer. Methyl orange (MO) increased the conductivity of PPy and induced the formation of MO doped PPy (PPy-MO) rectangular-shaped nanotubes. Using impedimetric detection, the rebinding of the template antigens was evaluated, the charge transfer resistance increased as the concentration of AFP and CEA increased. The linear dynamic ranges of 5-10 and 10-10 pg mL and detection limits of 1.6 and 3.3 pg mL were obtained for CEA and AFP, respectively. Given satisfactory results in the determination of AFP and CEA in the human serum samples, high sensitivity, and good stability of DMIP sensor made it a promising method for sensing of AFP and CEA in serum samples.
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http://dx.doi.org/10.1016/j.talanta.2021.123146DOI Listing
March 2022

Disposable Paper-Based Biosensors for the Point-of-Care Detection of Hazardous Contaminations-A Review.

Biosensors (Basel) 2021 Sep 4;11(9). Epub 2021 Sep 4.

Chemical Injuries Research Center, Systems Biology and Poisonings Institute, Baqiyatallah University of Medical Sciences, Tehran 19945, Iran.

The fast detection of trace amounts of hazardous contaminations can prevent serious damage to the environment. Paper-based sensors offer a new perspective on the world of analytical methods, overcoming previous limitations by fabricating a simple device with valuable benefits such as flexibility, biocompatibility, disposability, biodegradability, easy operation, large surface-to-volume ratio, and cost-effectiveness. Depending on the performance type, the device can be used to analyze the analyte in the liquid or vapor phase. For liquid samples, various structures (including a dipstick, as well as microfluidic and lateral flow) have been constructed. Paper-based 3D sensors are prepared by gluing and folding different layers of a piece of paper, being more user-friendly, due to the combination of several preparation methods, the integration of different sensor elements, and the connection between two methods of detection in a small set. Paper sensors can be used in chromatographic, electrochemical, and colorimetric processes, depending on the type of transducer. Additionally, in recent years, the applicability of these sensors has been investigated in various applications, such as food and water quality, environmental monitoring, disease diagnosis, and medical sciences. Here, we review the development (from 2010 to 2021) of paper methods in the field of the detection and determination of toxic substances.
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http://dx.doi.org/10.3390/bios11090316DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8464915PMC
September 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

Electrochemiluminescent biosensor for ultrasensitive detection of lymphoma at the early stage using CD20 markers as B cell-specific antigens.

Bioelectrochemistry 2021 Apr 28;138:107730. Epub 2020 Dec 28.

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

Herein, by taking advantage of the special binding of an aptamer to the membrane surface of a B cell and accumulation of the positive charges of a nanocomposite, including luminol-chitosan-platinum nanoparticles (L-Cs-Pt NPs), on the negatively charge of the aptamer phosphate backbone, a sensitive, simple, selective and rapid strategy for the detection of lymphoma cells by a new label-free electrogenerated chemiluminescence (ECL) aptasensor has been introduced. With increasing concentrations of B lymphoma cells, the nanocomposite detaches from the aptamer, leading to a decrease in the ECL of a luminol and HO system. With high loading of luminol and Pt NPs on a chitosan, together with the electrocatalytic effect of Pt NPs, enhanced sensitive detection of cancer cells with a limit of detection of 31 cells/mL was achieved. Step-by-step modification and biosensor response to cancer cells was monitored by electrochemical impedance spectroscopy (EIS), cyclic voltammetry (CV), and ECL. The aptasensor exhibited excellent specificity for lymphoma cells vs breast cancer (MCF-7) and human embryonic kidney (HEK293) cell lines as potential interferents. Finally, the performance of the aptasensor in blood samples was assessed against a commercial flow cytometric method. Satisfactory results confirmed the applicability of the proposed biosensing platform.
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http://dx.doi.org/10.1016/j.bioelechem.2020.107730DOI Listing
April 2021

Evaluation of Iranian Medical Journals from the Perspective of Publication Ethics.

Arch Iran Med 2020 10 1;23(10):697-703. Epub 2020 Oct 1.

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

Background: Scientific journals will gain real credit when they meet publication ethics standards. This study seeks to evaluate the current status of medical journals' adherence to some ethical standards.

Methods: The 412 scientific journals approved by the Ministry of Health and Medical Education were included in this study. The process of downloading articles and data extraction for seven general and specific indicators related to publication ethics was conducted by trained researchers. Different methods were implemented by the team of colleagues to prevent possible errors in data extraction. After data integration, data analysis was performed using SPSS version 23.

Results: Overall, 408 journals and 3948 articles met the inclusion criteria. The distribution of journals according to the highest journal index was 5.4%, 13.7%, 8.3%, 8.1% and 64.5% for ISI, ESCI, PubMed, Scopus and Other indexes, respectively. In 27.7% of the articles, the review process took over 6 months. According to the results, 6.6% and 31.7% of the articles belonged to the journals' editors and owner universities, respectively. Journal self-citation was seen in 19.2% of articles and in fewer than half of the articles (45.5%), the status of conflict of interest was declared. In 36.9% of the articles, the code of ethics or university ethics committee approval, and in 36.5% of clinical trial articles, the clinical trial registration code was reported.

Conclusion: Modifying processes or introducing new rules for indicators of publication ethics by trustee organizations can improve the current status. These seven indicators can also be used to rank journals.
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http://dx.doi.org/10.34172/aim.2020.88DOI Listing
October 2020

A paper-based colorimetric sensor array for discrimination and simultaneous determination of organophosphate and carbamate pesticides in tap water, apple juice, and rice.

Mikrochim Acta 2020 10 21;187(11):621. Epub 2020 Oct 21.

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

A colorimetric paper-based sensor is proposed for the rapid monitoring of six major organophosphate and carbamate pesticides. The assay was constructed by dropping gold and silver nanoparticles on the hydrophilic zones of a paper substrate. The nanoparticles were modified by L-arginine, quercetin, and polyglutamic acid. The mechanism of sensing is based on the interaction between the pesticide and the nanoparticles. The color of nanoparticles changed during the interactions. A digital camera recorded these changes. The assay provided a unique response for each studied pesticide. This method can determine six individual pesticides including carbaryl, paraoxon, parathion, malathion, diazinon, and chlorpyrifos. The limit of detection for these pesticides were 29.0, 22.0, 32.0, 17.0, 45.0, and 36.0 ng mL, respectively. The assay was applied to simultaneously determine the six studied pesticides in a mixture using the partial least square method (PLS). The root mean square errors of prediction were 11, 8.7, 9.2, 10, 12, and 11 for carbaryl, paraoxon, parathion, malathion, diazinon, and chlorpyrifos, respectively. The paper-based device can differentiate two types of studied pesticide (organophosphate and carbamate) as well as two types of organophosphate structures (oxon and thion). Furthermore, this sensor showed high selectivity to the pesticides in the presence of other potential species (e.g., metal ions, anions, amino acids, sugar, and vitamins). This assay is capable of determining the pesticide compounds in tap water, apple juice, and rice samples.Graphical abstract.
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http://dx.doi.org/10.1007/s00604-020-04596-xDOI Listing
October 2020

Optoelectronic nose based on an origami paper sensor for selective detection of pesticide aerosols.

Sci Rep 2020 10 14;10(1):17302. Epub 2020 Oct 14.

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

This study introduces an applicable colorimetric sensor array for the detection of pesticides in the vapor phase. The array consisted of six metal nanoparticles spotted on the piece of filter paper. 3D-origami pattern was used for the fabrication of a paper-based sensor to decrease the effect of the nanoparticles leaching after exposure to analytes. Exposure to pesticide aerosols caused changes in the color of the array due to the aggregation of nanoparticles. These changes provided selective responses to thion pesticides such as malathion, parathion, chlorpyrifos, and diazinon. The sensing assay could also differentiate between aliphatic and aromatic thions and discriminate amine-containing compounds from the other studied analytes. These finding results are clearly confirmed by both visual detection and multivariate statistical methods. The proposed sensor was successfully developed for the quantitative measurement of pesticide aerosols at a very low concentration. The limit of detection of this method determined for malathion, parathion, chlorpyrifos and diazinon were 58.0, 103.0, 81.0 and 117.0, respectively. Moreover, the array could be employed to simultaneously analyze four studied pesticides. The statistcal results confirmed that the method has high performance for concurrent detection of thions as a major air pollutant without the interference of other species.
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http://dx.doi.org/10.1038/s41598-020-74509-8DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7560735PMC
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

Two novel sets of [email protected] metal oxide/graphene oxide Z-scheme heterojunction: Insight into tetracycline and malathion photodegradation.

J Environ Sci (China) 2020 May 5;91:222-236. Epub 2020 Feb 5.

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

Nowadays, widespread researches have been focused on the development of effective photocatalysts to remove pollutants of the aquatic system. In accordance with the universal studies, two new sets of [email protected] metal oxide (including ZnO and TiO)/graphene oxide heterojunctions were synthesized for photodegradation of aromatic (tetracycline) and nonaromatic (malathion) pollutants which are challenging cases in the environment. The dosage of the photocatalyst, pH of the solution, the type of metal oxide, and the presence of various scavengers are assayed parameters in this work. In the optimum condition, maximum photodegradation efficiency is achieved in 90 min for tetracycline (81%) and malathion (100%) by the [email protected]/graphene oxide. The superior separation of charge carriers by Z-scheme mechanism, excellent electron mobility on layers of graphene oxide and high surface area are factors that enhanced the efficiency. Furthermore, in comparison with pure UiO-66, the band gaps belong to heterojunctions revealed a red shift in the absorption edge, which can be responsible for more expand adsorption of the solar spectrum. Total organic carbon analysis verified the decontamination of these pollutants in the solution. The produced main intermediates during the photocatalytic process were identified and the possible degradation pathway proposed. In general, the superior photocatalytic activity suggests that these designed photocatalysts can be a promising choice for having a clean future.
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http://dx.doi.org/10.1016/j.jes.2020.01.013DOI Listing
May 2020

Hospital Preparedness Plans for Chemical Incidents and Threats: A Systematic Review.

Disaster Med Public Health Prep 2020 08 15;14(4):477-485. Epub 2019 Oct 15.

Associate Professor of Emergency Medicine, Trauma and Injury Research Centre, Iran University of Medical Sciences, Tehran, Iran.

In a wide range of events, people may be acutely exposured to chemical substances. Particular hospital preparedness plans and vital resources are essential for appropriate health-care measures. The present study aimed to conduct a systematic review to summarize and evaluate the existing evidence on hospital preparedness plans or protocols against chemical incidents and threats. In this aim, through May 15, 2018, 5 electronic databases were searched in MEDLINE (PubMed, Scopus, Web of Science, Cochrane Library, and Google Scholar) for the following key words: hospital preparedness, plan, protocol, chemical incident, and chemical threat. The final review included 11 peer-reviewed papers that met inclusion criteria. The systematic review was performed using the Preferred Reporting Items for the Systematic reviews and Meta-Analysis protocol (PRISMA) (www.prisma-statement.org). Finally, of 16,540 selected papers, 11 papers were included in the final analysis. The thematic analyses revealed 11 major categories of chemical incidents and threats planning, such as planning requirements, planning prerequisites, preparation team member (multidisciplinary team), decontamination, personal protective equipment, education and training, job descriptions and roles, communication, database, staff /volunteer organization, as well as planning barriers and challenges for chemical incidents. Most countries have launched hospital preparedness planning against chemical incidents and threat activities, but the preparedness of hospitals is often less than desirable. Many items, such as databases, hospital preparation team members, communications, etc., are still challenging.
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http://dx.doi.org/10.1017/dmp.2019.91DOI Listing
August 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

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

Enhanced Visual Wireless Electrochemiluminescence Immunosensing of Prostate-Specific Antigen Based on the Luminol Loaded into MIL-53(Fe)-NH Accelerator and Hydrogen Evolution Reaction Mediation.

Anal Chem 2019 05 23;91(9):6383-6390. Epub 2019 Apr 23.

Chemical Injuries Research Center, Systems Biology and Poisonings Institute , Baqiyatallah University of Medical Sciences , 14359-16471 Tehran , Iran.

A sensitive prostate-specific antigen (PSA) detection method using a visual-readout closed bipolar electrode (BPE) system has been introduced by integration of hydrogen evolution reaction (HER) in cathodic pole and electrochemiluminescence (ECL) of luminol loaded within the MIL-53(Fe)-NH ([email protected](Fe)-NH) in the anodic pole. The cathode of the BPE was electrochemically synthesized by 3D porous copper foam, followed by decorating with nitrogen-doped graphene nanosheet and ruthenium nanoparticles. As an alternative, we employed carboxylate-modified magnetic nanoparticles (MNPs) for immobilization of the primary antibody (Ab1) and utilized the [email protected](Fe)-NH conjugated to secondary antibody (Ab2) as a signaling probe and coreaction accelerator. After sandwiching the target PSA between Ab1 and Ab2, the MNP/Ab1-PSA-Ab2/[email protected](Fe) were introduced to a gold anodic BPE. Finally, the resulting ECL of luminol and HO at the anodic poles was monitored using a photomultiplier tube (PMT) or digital camera. The PMT and visual (camera)-based detections showed linear responses from 1 pg mL to 300 ng mL (limit of detection 0.2 pg mL) and 5 pg mL to 200 ng mL (limit of detection 0.1 pg mL), respectively. This strategy provides an effective method for high-performance bioanalysis and opens a new door toward the development of the highly sensitive and user-friendly device.
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http://dx.doi.org/10.1021/acs.analchem.9b01506DOI Listing
May 2019

New portable smartphone-based PDMS microfluidic kit for the simultaneous colorimetric detection of arsenic and mercury.

RSC Adv 2018 Jul 30;8(48):27091-27100. Epub 2018 Jul 30.

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

A smartphone-based microfluidic platform was developed for point-of-care (POC) detection using surface plasmon resonance (SPR) of gold nanoparticles (GNPs). The simultaneous colorimetric detection of trace arsenic and mercury ions (As and Hg) was performed using a new image processing application (app). To achieve this goal, a microfluidic kit was fabricated using a polydimethylsiloxane (PDMS) substrate with the configuration of two separated sensing regions for the quantitative measurement of the color changes in GNPs to blue/gray. To fabricate the microfluidic kit, a Plexiglas mold was cut using a laser based on the model obtained from AutoCAD and Comsol outputs. The colorimetric signals originated from the formation of nanoparticle aggregates through the interaction of GNPs with dithiothreitol - 10,12-pentacosadiynoic acid (DTT-PCDA) and lysine (Lys) in the presence of As and Hg ions. This assembly exhibited the advantages of simplicity, low cost, and high portability along with a low volume of reagents and multiplex detection. Heavy Metals Detector (HMD), as a new app for the RGB reader, was programmed for an Android smartphone to quantify colorimetric analyses. Compared with traditional image processing, this app provided significant improvements in sensitivity, time of analysis, and simplicity because the color intensity is measured through a new normalization equation by converting RGB to an Integer system. As a simple, real-time, and portable analytical kit, the fabricated sensor could detect low concentrations of As (710 to 1278 μg L) and Hg (10.77 to 53.86 μg L) ions in water samples at ambient conditions.
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http://dx.doi.org/10.1039/c8ra04006kDOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC9083246PMC
July 2018

Extraction and determination of trace amounts of three anticancer pharmaceuticals in urine by three-phase hollow fiber liquid-phase microextraction based on two immiscible organic solvents followed by high-performance liquid chromatography.

J Sep Sci 2018 Aug 25;41(15):3113-3120. Epub 2018 Jun 25.

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

An automated three-phase hollow fiber liquid-phase microextraction based on two immiscible organic solvents followed by high-performance liquid chromatography with UV-Vis detection method was applied for the extraction and determination of exemestane, letrozole, and paclitaxel in water and urine samples. n-Dodecane was selected as the supported liquid membrane and its polarity was justified by trioctylphosphine oxide. Acetonitrile was used as an organic acceptor phase with desirable immiscibility having n-dodecane. All the effective parameters of the microextraction procedure such as type of the organic acceptor phase, the supported liquid membrane composition, extraction time, pH of the donor phase, hollow fiber length, stirring rate, and ionic strength were evaluated and optimized separately by a one variable at-a-time method. Under the optimal conditions, the linear dynamic ranges were 1.8-200 (R  = 0.9991), 0.9-200 (R  = 0.9987) and 1.2-200 μg/L (R  = 0.9983), and the limits of detection were 0.6, 0.3, and 0.4 μg/L for exemestane, letrozole, and paclitaxel, respectively. To evaluate the capability of the proposed method in the analysis of biological samples, three different urinary samples were analyzed under the optimal conditions. The relative recoveries of the three pharmaceuticals were in the range of 91-107.3% for these three analytes.
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http://dx.doi.org/10.1002/jssc.201800183DOI Listing
August 2018

Voltammetric determination of 4-nitrophenol using a glassy carbon electrode modified with a gold-ZnO-SiO nanostructure.

Mikrochim Acta 2018 05 11;185(6):296. Epub 2018 May 11.

Chemical Injuries Research Center, Systems Biology and Poisonings Institute, Baqiyatallah University of Medical Sciences, P.O. Box 1435916-471, Tehran, Iran.

A nanostructured material of the type Au-ZnO-SiO is described that consists of ZnO and gold nanoparticles (NPs) dispersed into a silica matrix and used to construct a voltammetric sensor for 4-nitrophenol. The AuNPs and ZnO NPs are anchored onto the silica network which warrants the nanostructures to be stable in various environments. It also facilitates the electron transfer between the electrolyte and the glassy carbon electrode (GCE). The properties of the nanostructure as a modifier for the GCE were investigated by energy dispersive spectrometry, X-ray diffraction spectroscopy, and transmission electron microscopy. It is shown that the nanostructure increases the surface area. Hence, the cathodic and anodic current in differential pulse voltammetry of 4-nitrophenol are considerably enhanced in comparison to a bare GCE. Under optimum conditions, the currents for oxidation and reduction are proportional to the concentration of 4-nitrophenol in the 0.05-3.5 μM and 0.01-1.2 μM concentration ranges, with 13.7 and 2.8 nM detection limits, respectively. The sensor has excellent sensitivity, fast response, long-term stability, and good reproducibility. It is perceived to be a valuable tool for monitoring 4-nitrophenol in real water samples. Graphical abstract Schematic of voltammetric sensor for 4-nitrophenol. It is based on GCE modified with gold-ZnO-SiO nanostructure. It exhibited the improvement in performance for both oxidation and reduction peaks in terms of linearity, concentration range, detection limit, and sensitivity.
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http://dx.doi.org/10.1007/s00604-018-2840-4DOI Listing
May 2018

A nanocomposite prepared from a zinc-based metal-organic framework and polyethersulfone as a novel coating for the headspace solid-phase microextraction of organophosphorous pesticides.

Mikrochim Acta 2017 12 18;185(1):62. Epub 2017 Dec 18.

Toxicology and Poisoning Research Center, Department of Toxicology, Faculty of Veterinary Medicine, University of Tehran, P.O. Box 14155-6453, Tehran, Iran.

The authors describe a zinc-based metal-organic framework/polyethersulfone nanocomposite (TMU-4/PES) coating deposited on a stainless steel wire via a single-phase inversion method. The nanocomposite represents a novel fiber coating for headspace solid-phase microextraction of organophosphorous pesticides (OPPs) from environmental water and soil samples. The synergistic effects of the high surface area and unique porous structure of TMU-4 as well as the rich π electron stacking and mechanical attributes of the PES polymer result in a high affinity of the composite for OPPs. Following thermal desorption, the OPPS were quantified by gas chromatography with a nitrogen-phosphorus detector. The preparation of the coating is simple, and the coated fiber is highly stable and reusable in that it can be used in about 100 consecutive extractions/desorption cycles. A central composite design was used for assessing the effect of the experimental parameters on the extraction process. Under optimized conditions, the limits of detection are in the 5-8 ng mL range for the OPPs diazinon, fenitrothion, malathion and chlorpyrifos. The average repeatability and fiber-to-fiber reproducibility are 6.5% and 8.7%, respectively. The method was applied to the trace determination of OPPs in (spiked) water and soil samples where it gave good recovery (88-108%) and satisfactory reproducibility (5.9-10.1%). Graphical abstract A zinc-based metal-organic framework/polyethersulfone nanocomposite coating was prepared on a stainless steel wire via phase inversion. It was used as a novel fiber coating for headspace solid phase microextraction of organophosphorous pesticides from water and soil samples.
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http://dx.doi.org/10.1007/s00604-017-2607-3DOI Listing
December 2017

Development of a molecularly imprinted polymer tailored on disposable screen-printed electrodes for dual detection of EGFR and VEGF using nano-liposomal amplification strategy.

Biosens Bioelectron 2018 Jun 3;107:26-33. Epub 2018 Feb 3.

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

This work demonstrates the development of a gold screen-printed electrode (Au-SPE)-based biosensor modified with a molecularly imprinted polymer and amplified using antibody-conjugated nano-liposomes. The developed biosensor was utilized for dual determination of epidermal growth factor receptor (EGFR) and vascular endothelial growth factor (VEGF) as cancer biomarkers. To prepare this biosensor, Au-SPE was modified with 3,3'-dithiodipropionic acid di(N-hydroxysuccinimide ester) via self-assembly method and then the target proteins (EGFR and VEGF) were covalently attached to the modified SPE. To synthesize the molecularly imprinted polymer, monomers of acrylamide and N,N'-methylenebis(acrylamide) were polymerized around the EGFR and VEGF templates, and to characterize the prepared biosensor, electrochemical impedance spectroscopy was used for analyses of surface changes in the engineered electrodes. To produce reliable electrochemical signals, nano-liposomes which were loaded with Cd(II) and Cu(II) cations and decorated with antibodies specific for EGFR and VEGF were used as an efficient tool for detection of target biomarkers. In the analysis step, potentiometric striping analysis (PSA), as an electrochemical technique, was utilized for sensitive determination of these cations. The limits of detection (LODs) of EGFR and VEGF analyses were found to be 0.01 and 0.005 pg mL with the linear dynamic ranges (LDRs) of 0.05-50000 and 0.01-7000 pg mL, respectively. Moreover, the proposed biosensor was successfully used for sensitive, reproducible, and specific detection of EGFR and VEGF in real samples. Due to the SPE nature of the developed biosensor, we envision that this sensing tool has capability of being integrated with lab-on-a-chip (LOC), microfluidics, and micro total analysis systems.
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http://dx.doi.org/10.1016/j.bios.2018.02.005DOI Listing
June 2018

Fabrication of a novel aptasensor based on three-dimensional reduced graphene oxide/polyaniline/gold nanoparticle composite as a novel platform for high sensitive and specific cocaine detection.

Anal Chim Acta 2017 Dec 31;996:10-19. Epub 2017 Oct 31.

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

In the present research, we have developed a novel label free aptasensor based on screen printed carbon electrode (SPCE) modified with three-dimensional magnetic reduced graphene oxide(3D-MRGO)/polyaniline(PA)/gold nanoparticle(AuNP) nanocomposite for impedimetric determination of cocaine. To achieve this goal, a specific thiolated cocaine aptamer was immobilized onto the surface of synthesized nanocomposite. The signaling mechanism of the proposed aptasensor was based on increase in the [Fe(CN)] charge transfer resistance (R) as an electrochemical probe in the presence of target analyte. In order to collect of 3D-MRGO/PA/AuNP/aptamer on the surface of working electrode easily, a new electrochemical cell was fabricated. The advantages of the new electrochemical cell configuration can be counted as reusing SPCE for several times, obtaining repeatable responses, reducing required volume of electrolyte and probe solution and making proposed method more user-friendly. Cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS), scanning electron microscopy (SEM) and Fourier transform infrared spectroscopy (FT-IR) were used for the characterization of synthesized nanocomposite and modified electrode surface. Under optimized condition, cocaine was determined in a linear concentration range from 0.09 to 85 nM with a detection limit of 0.029 nM by EIS. Also, in order to test applicability of the proposed aptasensor, it was applied to determine cocaine in urine and serum samples and satisfactory results were obtained.
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http://dx.doi.org/10.1016/j.aca.2017.10.035DOI Listing
December 2017

Visual electrochemiluminescence biosensing of aflatoxin M1 based on luminol-functionalized, silver nanoparticle-decorated graphene oxide.

Biosens Bioelectron 2018 Feb 21;100:382-388. Epub 2017 Sep 21.

Department of Chemistry, University of Isfahan, Isfahan 81746-73441, Iran.

A sensitive electrochemiluminescence (ECL) aptasensor for aflatoxin M1 (AFM1) detection by a closed bipolar electrode (BPE) array has been introduced. The thiolated AFM1 aptamer was immobilized on gold nanoparticle-coated magnetic FeO nanoparticles (Apt-GMNPs). Luminol-functionalized silver nanoparticle-decorated graphene oxide (GO-L-AgNPs) participates in π-π interactions with the unpaired bases of the immobilized aptamer (Apt-GMNPs-GO-L-AgNPs). After the Apt-GMNPs-GO-L-AgNPs were introduced to a gold anodic BPE array, the individual electrodes were subjected to different concentrations of AFM1. Upon the interaction of AFM1 with the aptamers, the GO-L-AgNPs detach from the aptamer; the resulting ECL of luminol and HO at the anodic poles is monitored using a photomultiplier tube (PMT) or smartphone, and the images are analyzed using ImageJ software. This process triggers thionine reduction at the cathodic poles. Under the optimal conditions obtained by a face-centered central composite design (FCCD), the PMT-based detection of the BPE-ECL aptasensor exhibit a linear response over a wide dynamic range from 5 to 150ngmL, with a detection limit of 0.01ngmL. Additionally, smartphone-based detection shows a linear relationship between the ECL image gray value and the logarithmic concentration of the AFM1 target over a range of 10-200ngmL, with a detection limit of 0.05ngmL. Furthermore, the BPE-ECL aptasensor was successfully used to detect AFM1 in milk complex media without any serious interferences with reliable reproducibility (average relative standard deviation (RSD = 2.3%)). This smartphone-based detection opens a new horizon for bioanalysis that does not require a trained technician to operate and is a promising technology for point-of-care testing.
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http://dx.doi.org/10.1016/j.bios.2017.09.035DOI Listing
February 2018

Graphene nanoribbon/FePt bimetallic nanoparticles/uric acid as a novel magnetic sensing layer of screen printed electrode for sensitive determination of ampyra.

Talanta 2018 Jan 16;176:350-359. Epub 2017 Aug 16.

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

A novel electrochemical sensor for sensitive determination of ampyra (Am) based on graphene nanoribbons modified by iron-platinum bimetallic nanoparticles and uric acid (SPCE/FePtGNR/UA) dropped on the screen-printed carbon electrode (SPCE) surface and magnetically captured onto an SPCE working electrode surface is reported in the present work. The modified nanocomposite and sensing layer was characterized by different techniques, including cyclic voltammetry (CV), linear sweep voltammetry (LSV), electrochemical impedance spectroscopy (EIS), transmission electron microscopy (TEM), Fourier transform infrared spectroscopy (FT-IR) and X-ray powdered diffraction (XRD). Am determination by conventional electrochemical methods is not possible, because of its high redox overpotential. Therefore, the differential pulse voltammetry (DPV) signals of UA were used as a redox probe for indirect electrochemical determination of Am. The limit of detection (LOD) and linear concentration range were obtained as 0.028 and 0.08-9.0µmolL (3S/m = 3), respectively. The feasibility of the proposed method was examined by the detection of Am in biological and pharmaceutical samples with satisfactory results. The constructed electrochemical sensor was applied for fast, simple and sensitive detection of Am in real environments.
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http://dx.doi.org/10.1016/j.talanta.2017.08.046DOI Listing
January 2018
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