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Spectrofluorimetric study of the complexation of ochratoxin A and Cu2+: Towards the hybrid fluorimetric sensor and visual detection of ochratoxin A in wheat flour samples from?…

Naader Alizadeh, Javad Hashemi, Faezeh Shahdost-Fard
Journal PapersFood Chemistry , Volume 350 , 2021 July 15, {Pages 129204 }

Abstract

In this study, the ochratoxin A (OTA) interaction with some metal cations exhibits a quenching effect of the Cu2+, Co2+, and Ni2+ in the OTA intrinsic fluorescence intensity. The property of the OTA fluorescence change in complexation with the Cu2+ has been applied in developing a label-free and selective fluorimetric sensor for fast detection of the OTA trace amounts in wheat flour samples. The achieved color difference map (CDM) based on the spectral profile provides the technical support for the rapid visual sensing of OTA in the wheat flour samples. The feasibility of the hybrid fluorimetric sensor and visual OTA detection in wheat flour samples has been confirmed with the high-performance liquid chromatography (HPLC) method as a standa

Noninvasive Detection of Ammonia in the Breath of Hemodialysis Patients Using a Highly Sensitive Ammonia Sensor Based on a Polypyrrole/Sulfonated Graphene Nanocomposite

Atefeh Shahmoradi, Abolghasem Hosseini, Alireza Akbarinejad, Naader Alizadeh
Journal PapersAnalytical Chemistry , 2021 April 21, {Pages }

Abstract

In this work, we fabricated fast-responsive and highly sensitive chemiresistive sensors based on nanocomposites of polypyrrole and graphitic materials such as graphene oxide (GO), reduced graphene oxide (RGO), and sulfonated graphene (SRGO) by an in situ chemical oxidative polymerization method. The synthesized nanocomposites were characterized using field emission scanning electron microscopy (FESEM), energy-dispersive spectroscopy (EDS), Fourier transform infrared (FT-IR) spectroscopy, and X-ray diffraction (XRD). The effects of the operating temperature of different nanocomposites were investigated at four temperatures (28, 40, 50, and 60 ?C), and the results were compared with that of the polypyrrole-based sensor. The experimental resul

Rapid simultaneous determination of ketamine and midazolam in biological samples using ion mobility spectrometry combined by headspace solid-phase microextraction

S Nakhodchi, N Alizadeh
Journal Papers , , {Pages }

Abstract

Spectrofluorimetric study of the complexation of ochratoxin A and Cu2+: Towards the hybrid fluorimetric sensor and visual detection of ochratoxin A in wheat flour samples from …

N Alizadeh, J Hashemi, F Shahdost-Fard
Journal Papers , , {Pages }

Abstract

Highly photosensitive near infrared photodetector based on polypyrrole nanoparticle incorporated with CdS quantum dots

Mahsa Amiri, Naader Alizadeh
Journal PapersMaterials Science in Semiconductor Processing , Volume 111 , 2020 June 1, {Pages 104964 }

Abstract

Photoconductive films in near-infrared (NIR) were fabricated based on low bandgap (1.36?eV) polypyrrole (PPy) and polypyrrole doped with cadmium sulfide quantum dots (PPy/CdS QDs) as organic photodetectors (PDs). The performance of the PDs was evaluated when the PPy incorporated with different amounts of CdS QDs during the chemical polymerization. The represented PDs showed good photosensitivity at 850?nm with different light intensities (0.4–173?mW) and their responses were linear dependency with increasing the light intensities. The best photosensitivity behavior was obtained when the PPy doped with 22?ppm of CdS QDs and the photoresponsivity was enhanced almost six times compared to the undoped PPy PD. The PPy/CdS QDs (22?ppm) PD exhib

Mid-infrared photoconductivity of polypyrrole doped with cadmium sulfide quantum dots

Mahsa Amiri, Naader Alizadeh
Journal PapersJournal of Physics and Chemistry of Solids , 2020 January 30, {Pages 109383 }

Abstract

We report the facile (one-step) in situ doping of soluble conducting polypyrrole (PPy) with cadmium sulfide quantum dots (CdS QDs) aimed at tuning the mid-infrared (MIR) (2.5–25 μm) photoconductivity of PPy films with a planer structure. The doping was done during chemical polymerization of PPy with different mass ratios (0–1800 ppm) of the as-synthesized CdS QDs. The PPy/CdS QD films were fabricated by electrospray coating between gold interdigitated electrodes. The incident light in the MIR region (7.62 mW/cm2) was chopped, the prepared film was illuminated with it, and the photocurrent generated was recorded. Doping with CdS QDs at 2–15 ppm increased the photoconductivity of PPy as they generated greater photocurrent than

Simultaneous determination of sertraline, imipramine and alprazolam in human plasma samples using headspace solid phase microextraction based on a nanostructured polypyrrole

Erfan Barati, Naader Alizadeh
Journal PapersAnalytical Methods , 2020 January , {Pages }

Abstract

This paper describes the development of a simple, rapid, and sensitive method based on headspace solid-phase microextraction (HS-SPME) combined with ion mobility spectrometry (IMS) for the simultaneous determination of antidepressant drugs, sertraline (SER), imipramine (IMI) and alprazolam (ALP), in human plasma samples. IMS equipped with corona discharge (CD) ionization along with HS-SPME has been successfully applied for quantitative analysis without derivatization steps. A dodecylbenzenesulfonate doped polypyrrole coating was used as a fiber for HS-SPME. The effects of various parameters on microextraction efficiency, including extraction temperature, extraction time, ionic strength, salt concentration and pH of the sample, were also eva

Vertically grown nanosheets conductive polypyrrole as a sorbent for nanomolar detection of salicylic acid

Navid Taheri, Naader Alizadeh
Journal PapersJournal of Pharmaceutical and Biomedical Analysis , 2020 May 24, {Pages 113365 }

Abstract

A selective detection strategy for salicylic acid (SA) based on the electrosorption/electrodesorption process using an electrochemically controlled solid phase extraction (EC-SPME) configuration is presented. We used conducting polymer polypyrrole (PPy) bearing the anionic dopant nitrate (PPy/nitrate) as a sorbent element for the extraction of SA in plasma and urine samples. The vertically grown nanosheets conducting film was directly synthesized by cyclic voltammetry method on a rod-shaped stainless steel electrode. The prepared electrode was employed for selective electrosorption of SA from sample solutions by applying positive potential and following its successive electrodesorption by the use of negative potential. Several parameters li

Highly selective detection of methanol in aqueous and ethanol medium based on hybrid ZnS: Mn2+ quantum dots/N-methylpolypyrrole as a fluorescence switchable sensor

Fatemeh Abbasi, Naader Alizadeh
Journal PapersFood Chemistry , 2020 May 18, {Pages 127091 }

Abstract

Methanol is highly toxic for human, so methanol detection is valuable especially in water and ethanol medium without complicated and time consuming procedure. In this work, we present a new fluorescence probe for direct detection of methanol in aqueous and ethanol medium based on the ZnS:Mn2+ quantum dot (QDs) and soluble N-methylpolypyrrole (NMPPy) hybrid. Moreover, the number of spectroscopic techniques were used to study the chemical composition and optical properties of the resultant QDs as well as investigation on the sensing mechanism toward methanol. Also, methanol can be determined by using ZnS:Mn2+ QDs/NMPPy hybrid based switchable fluorescence sensing system, with high sensitivity, high selectivity and a very good detection limit

Gas-phase study of adduct and exchange complexation reactions between two and tridimensional macrocyclic ligands using ion mobility spectrometry and mass spectrometry

Naader Alizadeh, Razieh Parchami, Edwin De Pauw, Mahmoud Tabrizchi
Journal PapersInternational Journal of Mass Spectrometry , 2020 December 25, {Pages 116512 }

Abstract

A gas-phase study concerning the interaction between macrocyclic ligands and different molecular ion guests (H3O+, NH4+, CH3NH3+) was performed using ion mobility spectrometry and mass spectrometry. 18-crown-6 (18C6), diaza18-crown-6 (DA18C6) and cryptand [222] (C222) ligands were selected for the investigation of structural properties on the nature of complexes formed. Characterization of complexes was performed by ESI-TWIM-TOFMS. In this study, the importance of the type of donating atom in the ring on complex formation was investigated by comparison of the ion mobility spectra of 18C6 and DA18C6 at various temperatures. Different complexation behaviors of ligands showed that the nature of species formed strongly depends on the structural

Highly selective detection of methanol in aqueous and ethanol medium based on hybrid ZnS: Mn2+ quantum dots/N-methylpolypyrrole as a fluorescence switchable sensor

Fatemeh Abbasi, Naader Alizadeh
Journal PapersFood Chemistry , Volume 328 , 2020 October 30, {Pages 127091 }

Abstract

Methanol is highly toxic for human, so methanol detection is valuable especially in water and ethanol medium without complicated and time consuming procedure. In this work, we present a new fluorescence probe for direct detection of methanol in aqueous and ethanol medium based on the ZnS:Mn2+ quantum dot (QDs) and soluble N-methylpolypyrrole (NMPPy) hybrid. Moreover, the number of spectroscopic techniques were used to study the chemical composition and optical properties of the resultant QDs as well as investigation on the sensing mechanism toward methanol. Also, methanol can be determined by using ZnS:Mn2+ QDs/NMPPy hybrid based switchable fluorescence sensing system, with high sensitivity, high selectivity and a very good detection limit

Mid-infrared photoconductivity of polypyrrole doped with cadmium sulfide quantum dots

Mahsa Amiri, Naader Alizadeh
Journal PapersJournal of Physics and Chemistry of Solids , Volume 141 , 2020 June 1, {Pages 109383 }

Abstract

We report the facile (one-step) in situ doping of soluble conducting polypyrrole (PPy) with cadmium sulfide quantum dots (CdS QDs) aimed at tuning the mid-infrared (MIR) (2.5–25?μm) photoconductivity of PPy films with a planer structure. The doping was done during chemical polymerization of PPy with different mass ratios (0–1800?ppm) of the as-synthesized CdS QDs. The PPy/CdS QDs films were fabricated by electrospray coating between gold interdigitated electrodes. The incident light in the MIR region (7.62?mW/cm2) was chopped, the prepared film was illuminated with it, and the photocurrent generated was recorded. Doping with CdS QDs at 2–15?ppm increased the photoconductivity of PPy as they generated greater photocurrent than the und

Simultaneous determination of sertraline, imipramine and alprazolam in human plasma samples using headspace solid phase microextraction based on a nanostructured polypyrrole?…

Erfan Barati, Naader Alizadeh
Journal PapersAnalytical Methods , Volume 12 , Issue 7, 2020 January , {Pages 930-937 }

Abstract

This paper describes the development of a simple, rapid, and sensitive method based on headspace solid-phase microextraction (HS-SPME) combined with ion mobility spectrometry (IMS) for the simultaneous determination of antidepressant drugs, sertraline (SER), imipramine (IMI) and alprazolam (ALP), in human plasma samples. IMS equipped with corona discharge (CD) ionization along with HS-SPME has been successfully applied for quantitative analysis without derivatization steps. A dodecylbenzenesulfonate doped polypyrrole coating was used as a fiber for HS-SPME. The effects of various parameters on microextraction efficiency, including extraction temperature, extraction time, ionic strength, salt concentration and pH of the sample, were also eva

Vertically grown nanosheets conductive polypyrrole as a sorbent for nanomolar detection of salicylic acid

N Taheri, N Alizadeh
Journal Papers , , {Pages }

Abstract

Highly photosensitive near infrared photodetector based on polypyrrole nanoparticle incorporated with CdS quantum dots

M Amiri, N Alizadeh
Journal Papers , , {Pages }

Abstract

Simultaneous determination of sertraline, imipramine and alprazolam in human plasma samples using headspace solid phase microextraction based on a nanostructured polypyrrole …

E Barati, N Alizadeh
Journal Papers , , {Pages }

Abstract

CdS QDs/N-methylpolypyrrole hybrids as fluorescent probe for ultrasensitive and selective detection of picric acid

Fatemeh Abbasi, Alireza Akbarinejad, Naader Alizadeh
Journal PapersSpectrochimica Acta Part A: Molecular and Biomolecular Spectroscopy , Volume 216 , 2019 June 5, {Pages 230-235 }

Abstract

Inorganic-organic hybrids are an advanced class of luminescent materials showing great promise for fabrication of highly sensitive and selective optical sensors. In the present study, a novel CdS quantum dots/N-methylpolypyrrole (CdS QDs/NMPPY) hybrid was synthesized via the direct polymerization of NMPPY on L-cysteine capped CdS QD aggregates. A number of characterization techniques including FTIR, DLS, FESEM, UV–vis, and fluorescence spectroscopies were used to study the chemical composition, morphology and optical properties of the resultant QDs/polymer hybrid. The as-synthesized CdS QDs/NMPPY hybrid shows a bright emission at 459 nm under excitation at 367 nm in water. Also the results show the role of sodium dodecyl benzenesulfon

Ultrasensitive and selective QCM sensor for detection of trace amounts of nitroexplosive vapors in ambient air based on polypyrrole—Bromophenol blue nanostructure

Mohammad Reza Eslami, Naader Alizadeh
Journal PapersSensors and Actuators B: Chemical , Volume 278 , 2019 January 1, {Pages 55-63 }

Abstract

A new polypyrrole-bromophenol blue (PPy-BPB) compound was synthesized in nanosphere and nanorod forms on quartz crystal microbalance (QCM) gold electrode by direct one-step electrochemical deposition, and utilized for highly sensitive determination of nitroexplosive compounds’ vapors in the ambient temperature in open air and through a home-made vapor generation/test system. A series of QCM sensors modified with PPy doped with different bromine containing anions and the regular chloride dopant were prepared and used for sensing of nitroexplosives. The design entailed a PPy-BPB modified QCM sensor with very low limit of detections for nitroexplosives including; 500 ppt (v) for TNT, 800 ppt (v) for PETN, 1 ppb (v) for RDX and 2 ppb (v)

Synthesis of highly fluorescent water-soluble polypyrrole for cell imaging and iodide ion sensing

Naader Alizadeh, Alireza Akbarinejad, Saman Hosseinkhani, Fatemeh Rabbani
Journal PapersAnalytica chimica acta , Volume 1084 , 2019 November 25, {Pages 99-105 }

Abstract

Conjugated polymers for bioimaging and sensing chemical/biological reagents have received much attention owing to their outstanding photophysical properties. However, most conventional synthetic strategies result in aggregates of conjugated polymers with limited solubility in most common organic and aqueous solvents. Therefore, advancement in molecular design and synthetic pathways is required to tune the optical and solubility properties of the resulting conjugated polymers. Herein, a simple, general, and effective approach for the synthesis of water-soluble polypyrrole (PPy) is reported based on the chemical polymerization in the presence of a homologue series of dicarboxylic acids with different chain lengths as multifunctional dopant mo

Photothermal lens microfluidic sensor for femtomole detection of 2, 4, 6-trinitrotoluene based on Meisenheimer complexation

Javad Yoosefian, Naader Alizadeh
Journal PapersSensors and Actuators B: Chemical , Volume 298 , 2019 November 1, {Pages 126882 }

Abstract

Since the simple and accurate quantification of 2,4,6-trinitrotoluene (TNT) traces is still a challenge for analytical chemists, we employed a recently developed crossed-beam photothermal lens spectrometer for highly sensitive and selective determination of TNT through a well-known Meisenheimer complexation with n-butylamine (nBA). The colorless solution of TNT in dimethyl sulfoxide (DMSO) was changed to deep-red after the addition of nBA. Hence, we used a 532 nm diode laser as excitation source in photothermal lens investigations. All the instrumental parameters and chemical conditions such as chopper frequency, sample flow velocity, amine concentration and etc. were optimized. Photothermal lens measurements yielded a linear signal depende

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