19 results match your criteria: "Campus universitaire de Tunis El Manar[Affiliation]"

Enhancement of the Piezocatalytic Response of La-Doped BiFeO Nanoparticles by Defects Synergy.

Small

December 2024

CentraleSupélec, Laboratoire Structures, Propriétés et Modélisation des Solides, Université Paris-Saclay, UMR CNRS 8580, Gif-sur-Yvette, 91190, France.

Because of their intrinsic polarization and related properties, ferroelectrics attract significant attention to address energy transformation and environmental protection. Here, by using trivalent-ion-lanthanum doping of BiFeO nanoparticles (NPs), it is shown that defects and piezoelectric potential are synergized to achieve a high piezocatalytic effect for decomposing the model Rhodamine B (RhB) pollutant, reaching a record-high piezocatalytic rate of 21 360 L mol min (i.e.

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The development of cost-effective materials for fabricating electrodes is crucial for drug, pharmaceutical and environmental applications. This paper presents the synthesis and characterization of a novel polyketimine (PKI) membrane obtained by condensing partially of different weight percentages of oxidized polyvinyl alcohol and aminated polyether sulfone. Using the PKI membrane as a scaffold, we introduced laser-induced graphene electrodes (LIGEs) for the efficient electrochemical sensing of paracetamol (PCM), which serves as a model drug.

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BiFeO Nanoparticles: The "Holy-Grail" of Piezo-Photocatalysts?

Adv Mater

August 2023

Université Paris-Saclay, CentraleSupélec, Laboratoire Structures, Propriétés et Modélisation des Solides, UMR CNRS 8580, Gif-sur-Yvette, 91190, France.

Article Synopsis
  • Recent research highlights the use of piezoelectric catalysis, particularly with BiFeO nanoparticles, as an effective method for degrading pollutants like Rhodamine B (RhB), achieving high degradation rates.
  • These 60 nm-sized BiFeO nanoparticles achieve a remarkable 100% degradation of RhB in just 5 minutes when combined with sunlight, showcasing their potential for rapid environmental applications.
  • The BiFeO nanoparticles are embedded in a polymer matrix for improved stability and reusability, maintaining strong catalytic performance for various pollutants, thereby opening avenues for further research in water purification and other environmental processes.
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A General Synthetic Route to High-Quality Perovskite Oxide Nanoparticles and Their Enhanced Solar Photocatalytic Activity.

Angew Chem Int Ed Engl

February 2023

Université Paris-Saclay, CentraleSupélec, Laboratoire Structures, Propriétés et Modélisation des Solides, UMR CNRS 8580, 91190, Gif-sur-Yvette, France.

The main limitations of current methods for synthesizing perovskite oxide (ABO ) nanoparticles (NPs), e.g., the high reagent costs and sophisticated equipment, the long time and high-temperature processing, or multiple post-processing and thermal treatment steps, hamper their full study and potential application.

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Several tests were conducted to ratify the reliability and durability of the solar photovoltaic (PV) devices before deployment in the real field (non-ideal conditions). In the real field, the temperature of the PV modules was varied during the day and night. Nowadays, people have been bearing in mind the deployment of PV modules on concrete roads to make use of the space accessible on roads.

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In this work, we report on the design of an enzyme-less sensitive and selective electrochemical electrode for ascorbic acid (AA) detection using a modified screen-printed electrode of melanin-like nanoparticles (Mel-NPs). Cyclic voltammetry shows that the melanin-modified electrode exhibits high electrocatalytic activity for ascorbic acid. The melanin-like nanoparticles serve as a shuttle to transport electrons from ascorbic acid to the electrode surface.

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In the present work, an aptasensing platform was developed for the detection of a carcinogenic mycotoxin termed patulin (PAT) using a label-free approach. The detection was mainly based on a specific interaction of an aptamer immobilized on carbon-based electrode. A long linear spacer of carboxy-amine polyethylene glycol chain (PEG) was chemically grafted on screen-printed carbon electrodes (SPCEs) via diazonium salt in the aptasensor design.

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E-DNA detection of rpoB gene resistance in Mycobacterium tuberculosis in real samples using FeO/polypyrrole nanocomposite.

Biosens Bioelectron

March 2019

Univ. Paris Sud, Université Paris-Saclay, LCBB, Institut de Chimie Moléculaire et des Matériaux d'Orsay(UMR -CNRS 8182), Bât 420, 2 Rue du Doyen Georges Poitou, 91400 Orsay, France. Electronic address:

In this work, we achieved the selective detection of wild and mutated rpoB gene in M. tuberculosis using an electrochemical DNA (E-DNA) sensor based on polypyrrole/FeO nanocomposite bearing redox naphthoquinone tag on PAMAM (spaNQ/PAMAM/PPy/FeO). The hybridization between a given probe and the complementary DNA target induced a large decrease in the naphthoquinone redox signal as measured by SWV and no cross-hybridization with single nucleotide mismatch DNA target occurred.

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Design of a redox-active surface for ultrasensitive redox capacitive aptasensing of aflatoxin M1 in milk.

Talanta

April 2019

Université de Tunis El Manar, Faculté des Sciences de Tunis, Laboratoire de Chimie Analytique et Electrochimie (LR99ES15), Sensors and Biosensors Group, Campus Universitaire de Tunis El Manar, 2092 Tunis, Tunisia. Electronic address:

Herein, we report the design of a novel label-free aptasensor based on ferrocene and silicon nanoparticles (SiNPs) for ultrasensitive detection of aflatoxin M1 (AFM1) in milk. Given that silicon nanomaterials stand out by their high capacitive power, we used them to develop a novel capacitive transduction system based on electrochemical capacitance spectroscopy (ECS). This strategy relies on the changes of the redox capacitance signal owed to the surface-tethered ferrocene film, by performing electrochemical impedance spectroscopy (EIS) measurements without using an external redox probe.

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Curcumin-graphene quantum dots for dual mode sensing platform: Electrochemical and fluorescence detection of APOe4, responsible of Alzheimer's disease.

Anal Chim Acta

December 2018

University of Tunis El Manar, Faculty of Sciences of Tunis, Laboratory of Analytical Chemistry and Electrochemistry (LR99ES15), Sensors and Biosensors Group, Campus Universitaire de Tunis El Manar, Tunis El Manar, 2092, Tunis, Tunisia.

New dual electrochemical and fluorescence sensitive curcumin-graphene quantum dots sensing platform coated on the transparent Indium-Tin-Oxide electrode was developed to sense APOe4 DNA, responsible of Alzheimer's disease. Curcumin molecule with its dual fluorescence and electrochemical properties was electropolymerized on GQDs-ITO surface. EDC/NHS chemistry was used to covalently immobilize an amino-substituted DNA probe via a malonic acid spacer.

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Electrically controlled Michael addition: Addressing of covalent immobilization of biological receptors.

Biosens Bioelectron

December 2018

Department of Nanobiotechnology, Institute of Biotechnology, Brandenburg University of Technology Cottbus-Senftenberg, 01968 Senftenberg, Germany. Electronic address:

Electrically addressed covalent immobilization of biomolecules to the defined electrodes of an electrode array is described. It is based on Michael addition of the thiol group of biomolecules to α,β-unsaturated carbonyl groups of benzoquinone. This "click" reaction was tested by immobilization of a number of thiolated compounds on the simplest array consisting of two gold electrodes coated by a self-assembled monolayer of benzoquinone-terminated hexanethiol.

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Electrochemical immunoassay for lactalbumin based on the use of ferrocene-modified gold nanoparticles and lysozyme-modified magnetic beads.

Mikrochim Acta

September 2018

Faculty of Sciences of Tunis, Laboratory of Analytical Chemistry and Electrochemistry (LR99ES15), Sensors and Biosensors Group, University of Tunis El Manar, Campus Universitaire de Tunis El Manar, Tunis El Manar, 2092, Tunis, Tunisia.

The authors describe a method for electrochemical determination of the breast cancer biomarker α-lactalbumin (α-LA) using disposable screen-printed carbon electrodes (SPCEs). Lysozyme-conjugated FeO nanoparticles (Lys-FeONPs) were used to capture α-LA on the surface of the SPCEs which then is trapped in an immunosandwich using secondary antibodies labeled with ferrocene-modified gold nanoparticles. The amperometric response of ferrocene (recorded at +0.

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Ultrasensitive sensing of Androctonus australis hector scorpion venom toxins in biological fluids using an electrochemical graphene quantum dots/nanobody-based platform.

Talanta

December 2018

University of Tunis El Manar, Faculty of sciences of Tunis, Laboratory of Analytical Chemistry and Electrochemistry (LR99ES15), Sensors and Biosensors Group,  Campus Universitaire de Tunis El Manar, Tunis El Manar, 2092 Tunis, Tunisia.

Rapid and sensitive detection of low levels of scorpion venom toxins in biological fluids is of tremendous importance for decision-taking in cases of envenomation by scorpions stings. In Tunisia, at least 1200 severe envenomation cases by Androctonus australis hector (Aah) scorpion stings were reported annually. In this work, we report on a novel electrochemical immuno-sandwich to detect the Aah50 toxic fraction within the Aah scorpion venom using the bispecific nanobody format specially designed to highly recognize and neutralize the two most toxic molecules in the AahG50 venom fraction (i.

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Ferrocene-functionalized graphene electrode for biosensing applications.

Anal Chim Acta

July 2016

Catalan Institute of Nanoscience and Nanotechnology (ICN2), CSIC and The Barcelona Institute of Science and Technology, Campus UAB, Bellaterra, 08193 Barcelona, Spain; ICREA, Barcelona, Catalonia, Spain. Electronic address:

A novel ferrocene-functionalized reduced graphene oxide (rGO)-based electrode is proposed. It was fabricated by the drop casting of ferrocene-functionalized graphene onto polyester substrate as the working electrode integrated within screen-printed reference and counter electrodes. The ferrocene-functionalized rGO has been fully characterized using FTIR, XPS, contact angle measurements, SEM and TEM microscopy, and cyclic voltammetry.

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A naphthoquinone/SAM-mediated biosensor for olive oil polyphenol content.

Food Chem

October 2016

Université de Tunis El-Manar, Faculté des Sciences de Tunis, Département de Chimie, Laboratoire de Chimie Analytique & Electrochimie (LR99ES15), campus universitaire de Tunis El Manar, 2092 Tunis El-Manar, Tunisia. Electronic address:

We report on the design of an amperometric tyrosinase-based biosensor using a self-assembled monolayer of ω-mercaptopropyl naphthoquinone on gold electrode as an electron mediator. Under optimal conditions (i.e.

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The demand for on-site nanodevices is constantly increasing. The technology development for the design of such devices is highly regarded. In this work, we report the design of a disposable platform that is structured with cauliflower-shaped gold nanoparticles (cfAuNPs) and we show its applications in immunosensing and enzyme-based detection.

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Copper nanoparticles of well-controlled size and shape: a new advance in synthesis and self-organization.

Nanoscale

February 2015

Laboratoire de Chimie Analytique et Electrochimie, Département de Chimie, Faculté des Sciences de Tunis, Université de Tunis El Manar, campus universitaire de Tunis El Manar, 2092 Tunis El Manar, Tunisie.

Here, we report a new synthetic route for spherical small copper nanoparticles (CuNPs) with size ranging from 3.5 nm to 11 nm and with an unprecedented associated monodispersity (<10%). This synthesis is based on the reduction of an organometallic precursor (CuCl(PPh3)3) by tert-butylamine borane in the presence of dodecylamine (DDA) at a moderate temperature (50 to 100 °C).

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Various regulatory authorities like International Conference on Harmonization (ICH), US Food and Drug Administration, Canadian Drug and Health Agency are emphasizing on the purity requirements and the identification of impurities in active pharmaceutical drugs. Qualification of the impurities is the process of acquiring and evaluating data that establishes biological safety of an individual impurity; thus, revealing the need and scope of impurity profiling of drugs in pharmaceutical research. As no stability-indicating method is available for identification of degradation products of trandolapril, a new angiotensin converting enzyme inhibitor (ACEI), under stress testing, the development of an accurate method is needed for quantification and qualification of degradation products.

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Towards a characterization of the locomotor activity rhythm of the supralittoral isopod Tylos europaeus.

Chronobiol Int

March 2012

Unité de recherche Biologie Animale et Systématique Evolutive, Faculté des Sciences de Tunis, Campus Universitaire de Tunis El Manar I, Tunis, Tunisie.

Freshly collected samples of Tylos europaeus from Korba beach (northeast of Tunisia) were housed in an environmental cabinet at controlled temperature (18°C ± .5°C) and photoperiod. Locomotor activity was recorded under two photoperiodic regimens by infrared actography every 20 min by multichannel data loggers.

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