LIVIVO - Search results -

Search results

Result 1 - 10 of total 32

Search options

Article ; Online: The Effect of Composition on the Properties and Application of CuO-NiO Nanocomposites Synthesized Using a Saponin-Green/Microwave-Assisted Hydrothermal Method.

Al-Yunus, Amnah / Al-Arjan, Wafa / Traboulsi, Hassan / Hessien, Manal

International journal of molecular sciences

2024 Volume 25, Issue 7

Abstract: In this study, we explored the formation of CuO nanoparticles, NiO nanoflakes, and CuO-NiO nanocomposites using saponin extract and a microwave-assisted hydrothermal method. Five green synthetic samples were prepared using aqueous saponin extract and a ... ...

Abstract	In this study, we explored the formation of CuO nanoparticles, NiO nanoflakes, and CuO-NiO nanocomposites using saponin extract and a microwave-assisted hydrothermal method. Five green synthetic samples were prepared using aqueous saponin extract and a microwave-assisted hydrothermal procedure at 200 °C for 30 min. The samples were pristine copper oxide (100C), 75% copper oxide-25% nickel oxide (75C25N), 50% copper oxide-50% nickel oxide (50C50N), 25% copper oxide-75% nickel oxide (25C75N), and pristine nickel oxide (100N). The samples were characterized using FT-IR, XRD, XPS, SEM, and TEM. The XRD results showed that copper oxide and nickel oxide formed monoclinic and cubic phases, respectively. The morphology of the samples was useful and consisted of copper oxide nanoparticles and nickel oxide nanoflakes. XPS confirmed the +2 oxidation state of both the copper and nickel ions. Moreover, the optical bandgaps of copper oxide and nickel oxide were determined to be in the range of 1.29-1.6 eV and 3.36-3.63 eV, respectively, and the magnetic property studies showed that the synthesized samples exhibited ferromagnetic and superparamagnetic properties. In addition, the catalytic activity was tested against para-nitrophenol, demonstrating that the catalyst efficiency gradually improved in the presence of CuO. The highest rate constants were obtained for the 100C and 75C25N samples, with catalytic efficiencies of 98.7% and 78.2%, respectively, after 45 min.
MeSH term(s)	Copper ; Microwaves ; Spectroscopy, Fourier Transform Infrared ; Nanocomposites ; Saponins ; Oxides ; Nickel
Chemical Substances	nickel monoxide (C3574QBZ3Y) ; cuprous oxide (T8BEA5064F) ; Copper (789U1901C5) ; Saponins ; Oxides ; Nickel (7OV03QG267)
Language	English
Publishing date	2024-04-08
Publishing country	Switzerland
Document type	Journal Article
ZDB-ID	2019364-6
ISSN	1422-0067 ; 1422-0067 ; 1661-6596
ISSN (online)	1422-0067
ISSN	1422-0067 ; 1661-6596
DOI	10.3390/ijms25074119
Database	MEDical Literature Analysis and Retrieval System OnLINE

Order via subito

This service is chargeable due to the Delivery terms set by subito. Orders including an article and supplementary material will be classified as separate orders. In these cases, fees will be demanded for each order.

Article: Effect of pH and Nanoparticle Capping Agents on Cr (III) Monitoring in Water: A Kinetic Way to Control the Parameters of Ultrasensitive Environmental Detectors.

Awada, Chawki / Traboulsi, Hassan

Micromachines

2020 Volume 11, Issue 12

Abstract: In this work, we apply surface-enhanced Raman spectroscopy (SERS) to study the kinetics of chromium Cr (III) detection in solution using EDTA and silver nanoparticles (AgNPs). We examine for the first time the effect of pH and nanoparticles' capping ... ...

Abstract	In this work, we apply surface-enhanced Raman spectroscopy (SERS) to study the kinetics of chromium Cr (III) detection in solution using EDTA and silver nanoparticles (AgNPs). We examine for the first time the effect of pH and nanoparticles' capping agent on the kinetic mechanism of Cr (III) detection using SERS temporal variations. The full width at half maximum (FWHM) and Raman shift variations show that the mechanism of detection is composed of two steps: a first one consisting of chemical coordination between Cr (III) and AgNPs that leads to exalted chemical and electromagnetic enhancement and the second one is an aggregation process with an important optical enhancement. The obtained results showed that the first step in the detection at lower pH was five times faster than in a basic medium using citrate capped silver nanoparticles (Cit-AgNPs). On the other hand, using a capping agent with dicarboxylate groups such as oxalate (Oxa-AgNPs) led to an important enhancement in SERS detection signal (more than 30 times) compared with Cit-AgNPs, although the detection kinetic's mechanism was slower.
Language	English
Publishing date	2020-11-27
Publishing country	Switzerland
Document type	Journal Article
ZDB-ID	2620864-7
ISSN	2072-666X
ISSN	2072-666X
DOI	10.3390/mi11121045
Database	MEDical Literature Analysis and Retrieval System OnLINE

Order via subito

Article ; Online: Toward the Development of Ultrasensitive Detectors for Environmental Applications: A Kinetic Study of Cr(III) Monitoring in Water Using EDTA and SERS Techniques.

Traboulsi, Hassan / Awada, Chawki

ACS omega

2020 Volume 5, Issue 48, Page(s) 31352–31361

Abstract: We report for the first time kinetic studies on chromium(III) detection in aqueous solution using citrate-capped silver nanoparticles (AgNPs) and the surface-enhanced Raman spectroscopy (SERS) technique. Moreover, we have shown an important effect of ... ...

Abstract	We report for the first time kinetic studies on chromium(III) detection in aqueous solution using citrate-capped silver nanoparticles (AgNPs) and the surface-enhanced Raman spectroscopy (SERS) technique. Moreover, we have shown an important effect of adding ethylenediaminetetraacetic acid (EDTA) on the enhancement and the stability of the Raman signal. The origin of the SERS signal was attributed to the coordination of Cr(III) by citrate/EDTA molecules and the formation of hot spots on aggregated AgNPs. Depending on the mixing method of Cr(III) and EDTA with AgNPs, the temporal SERS spectral features reveal a Prout-Tompkins or a Langmuir kinetic detection model. The UV-visible data, the temporal response of the Raman signal, and the scanning electron microscopy analysis have allowed us to elucidate the mechanism of Cr(III) detection. We observed that mixing simultaneously Cr(III), AgNPs, and EDTA leads to the most stable and intense time-dependent SERS signal. The obtained results should open the way to perform kinetic studies on different host-guest interactions in solution using the SERS technique.
Language	English
Publishing date	2020-11-23
Publishing country	United States
Document type	Journal Article
ISSN	2470-1343
ISSN (online)	2470-1343
DOI	10.1021/acsomega.0c04844
Database	MEDical Literature Analysis and Retrieval System OnLINE

Order via subito

Inter-library loan at ZB MED

Your chosen title can be delivered directly to ZB MED Cologne location if you are registered as a user at ZB MED Cologne.

Article ; Online: Toward the Development of Ultrasensitive Detectors for Environmental Applications

Hassan Traboulsi / Chawki Awada

ACS Omega, Vol 5, Iss 48, Pp 31352-

A Kinetic Study of Cr(III) Monitoring in Water Using EDTA and SERS Techniques

2020 Volume 31361

Keywords	Chemistry ; QD1-999
Language	English
Publishing date	2020-11-01T00:00:00Z
Publisher	American Chemical Society
Document type	Article ; Online
Database	BASE - Bielefeld Academic Search Engine (life sciences selection)

Full text online

Full text

Inter-library loan at ZB MED

Your chosen title can be delivered directly to ZB MED Cologne location if you are registered as a user at ZB MED Cologne.

Article: Effect of Synthesis Conditions on CuO-NiO Nanocomposites Synthesized via Saponin-Green/Microwave Assisted-Hydrothermal Method.

Al-Yunus, Amnah / Al-Arjan, Wafa / Traboulsi, Hassan / Schuarca, Robson / Chando, Paul / Hosein, Ian D / Hessien, Manal

Nanomaterials (Basel, Switzerland)

2024 Volume 14, Issue 3

Abstract: This work presents the synthesis of CuO-NiO nanocomposites under different synthesis conditions. Nanocomposites were synthesized by merging a green synthesis process with a microwave-assisted hydrothermal method. The synthesis conditions were as follows: ...

Abstract	This work presents the synthesis of CuO-NiO nanocomposites under different synthesis conditions. Nanocomposites were synthesized by merging a green synthesis process with a microwave-assisted hydrothermal method. The synthesis conditions were as follows: concentration of the metal precursors (0.05, 0.1, and 0.2 M), pH (9, 10, and 11), synthesis temperature (150 °C, 200 °C, and 250 °C), microwave treatment time (15, 30, and 45 min), and extract concentration (20 and 40 mL of 1 g saponin/10 mL water, and 30 mL of 2 g saponin/10 mL water). The phases and crystallite sizes of the calcined nanocomposites were characterized using XRD and band gap via UV-Vis spectroscopy, and their morphologies were investigated using SEM and TEM. The XRD results confirmed the formation of a face-centered cubic phase for nickel oxide, while copper oxide has a monoclinic phase. The calculated crystallite size was in the range of 29-39 nm. The direct band gaps of the samples prepared in this work were in the range of 2.39-3.17 eV.
Language	English
Publishing date	2024-02-03
Publishing country	Switzerland
Document type	Journal Article
ZDB-ID	2662255-5
ISSN	2079-4991
ISSN	2079-4991
DOI	10.3390/nano14030308
Database	MEDical Literature Analysis and Retrieval System OnLINE

Order via subito

Article ; Online: Hierarchical Graphitic Carbon-Encapsulating Cobalt Nanoparticles for Catalytic Hydrogenation of 2,4-Dinitrophenol

Hassan H. Hammud / Hassan Traboulsi / Ranjith Kumar Karnati / Syed Ghazanfar Hussain / Esam M. Bakir

Catalysts, Vol 12, Iss 39, p

2022 Volume 39

Abstract: Cobalt hierarchical graphitic carbon nanoparticles (Co@HGC) ( 1 ), ( 2 ), and ( 3 ) were prepared by simple pyrolysis of a cobalt phenanthroline complex in the presence of anthracene at different temperatures and heating times, under a nitrogen ... ...

Abstract	Cobalt hierarchical graphitic carbon nanoparticles (Co@HGC) ( 1 ), ( 2 ), and ( 3 ) were prepared by simple pyrolysis of a cobalt phenanthroline complex in the presence of anthracene at different temperatures and heating times, under a nitrogen atmosphere. The samples were used for the catalytic hydrogenation of 2,4-dinitrophenol. Samples ( 1 ) and ( 3 ) were prepared by heating at 600 °C and 800 °C respectively, while ( 2 ) was prepared by heating at 600 °C with an additional intermediate stage at 300 °C. This work revealed that graphitization was catalyzed by cobalt nanoparticles and occurred readily at temperatures of 600 °C and above. The nanocatalysts were characterized by Scanning Electron Microscopy SEM, energy dispersive X-ray analysis EDX, Raman, Xrd, and XPS. The analysis revealed the presence of cobalt and cobalt oxide species as well as graphitized carbon, while TEM analysis indicated that the nanocatalyst contains mainly cobalt nanoparticles of 3–20 nm in size embedded in a lighter graphitic web. Some bamboo-like multiwall carbon nanotubes and graphitic onion-like nanostructures were observed in ( 3 ). The structures and chemical properties of the three catalysts were correlated with their catalytic activities. The apparent rate constants k app (min −1 ) of the 2,4-dinitrophenol reductions were 0.34 for ( 2 ), 0.17 for ( 3 ), 0.04 for ( 1 ), 0.005 (no catalyst). Among the three studied catalysts, the highest rate constant was obtained for ( 2 ), while the highest conversion yield was achieved by ( 3 ). Our data show that an increase in agglomeration of the cobalt species reduces the catalytic activity, while an increase in pyrolysis temperature improves the conversion yield. The nanocatalyst enhances hydrogen generation in the presence of sodium borohydride and reduces 2,4-dinitrophenol to p-diamino phenol. The best nanocatalyst ( 3 ) was prepared at 800 °C. It consisted of uniformly distributed cobalt nanoparticles sheltered by hierarchical graphitic carbon. The nanocatalyst is easily separated and recycled from the reaction system and proved to be degradation resistant, to have robust stability, and high activity towards the reduction reaction of nitrophenols.
Keywords	cobalt nanocarbon ; 2,4-dinitrophenol ; catalytic hydrogenation ; pyrolysis ; cobalt phenanthroline complex ; Chemical technology ; TP1-1185 ; Chemistry ; QD1-999
Subject code	540
Language	English
Publishing date	2022-12-01T00:00:00Z
Publisher	MDPI AG
Document type	Article ; Online
Database	BASE - Bielefeld Academic Search Engine (life sciences selection)

Full text online

Full text

Inter-library loan at ZB MED

Your chosen title can be delivered directly to ZB MED Cologne location if you are registered as a user at ZB MED Cologne.

Article ; Online: Development of superior antibodies against the S-protein of SARS-Cov-2 using macrocyclic epitopes.

Traboulsi, Hassan / Khedr, Mohammed A / Elgorashe, Rafea / Al-Faiyz, Yasair / Negm, Amr

Arabian journal of chemistry

2021 Volume 15, Issue 3, Page(s) 103631

Abstract: One of the proven methods to prevent and inhibit viral infections is to use antibodies to block the initial Receptor Binding Domain (RBD) of SARS-CoV-2 S protein and avoid its binding with the host cells. Thus, developing these RBD-targeting antibodies ... ...

Abstract	One of the proven methods to prevent and inhibit viral infections is to use antibodies to block the initial Receptor Binding Domain (RBD) of SARS-CoV-2 S protein and avoid its binding with the host cells. Thus, developing these RBD-targeting antibodies would be a promising approach for treating the SARS-CoV-2 infectious disease and stop virus replication. Macrocyclic epitopes constitute closer mimics of the receptor's actual topology and, as such, are expected to be superior epitopes for antibody generation. This work demonstrated the vital effect of the three-dimensional shape of epitopes on the developed antibodies' activity against RBD protein of SARS-CoV-2. The molecular dynamics studies showed the greater stability of the cyclic epitopes in comparison with the linear counterpart, which was reflected in the activity of their produced antibodies. Indeed, the antibodies we developed using macrocyclic epitopes showed superiority with respect to binding to RBD proteins compared to antibodies formed from a linear peptide. The results of the present work constitute a roadmap for developing superior antibodies that could be used to inhibit the activity of the SARS-CoV-2 and prevent its reproduction.
Language	English
Publishing date	2021-12-10
Publishing country	Saudi Arabia
Document type	Journal Article
ISSN	1878-5379
ISSN (online)	1878-5379
DOI	10.1016/j.arabjc.2021.103631
Database	MEDical Literature Analysis and Retrieval System OnLINE

Order via subito

Inter-library loan at ZB MED

Your chosen title can be delivered directly to ZB MED Cologne location if you are registered as a user at ZB MED Cologne.

Article ; Online: Structure-Based Epitope Design: Toward a Greater Antibody-SARS-CoV-2 RBD Affinity.

Traboulsi, Hassan / Khedr, Mohammed A / Al-Faiyz, Yasair S S / Elgorashe, Rafea / Negm, Amr

ACS omega

2021 Volume 6, Issue 47, Page(s) 31469–31476

Abstract: Efficient COVID-19 vaccines are widely acknowledged as the best way to end the global pandemic. SARS-CoV-2 receptor-binding domain (RBD) plays fundamental roles related to cell infection. Antibodies could be developed to target RBD and represent a ... ...

Abstract	Efficient COVID-19 vaccines are widely acknowledged as the best way to end the global pandemic. SARS-CoV-2 receptor-binding domain (RBD) plays fundamental roles related to cell infection. Antibodies could be developed to target RBD and represent a potential approach for the neutralization of the virus. Epitopes used to produce antibodies are generally linear peptides and thus possess multiple confirmations that do not reflect the actual topology of the targeted part in the native protein. On the other hand, macrocyclic epitopes could constitute closer mimics of the native protein topology and, as such, could generate superior antibodies. In this study, we demonstrated the vital effect of the size and the three-dimensional shape of epitopes on the activity of the developed antibodies against the RBD of SARS-CoV-2. The molecular dynamics studies showed the greater stability of the cyclic epitopes compared with the linear counterparts, which was reflected in the affinity of the produced antibodies. The antibodies developed using macrocyclic epitopes showed superiority with respect to binding to RBD compared to antibodies formed from linear peptides. This study constitutes a roadmap for developing superior antibodies that could be used to inhibit the activity of SARS-CoV-2.
Language	English
Publishing date	2021-11-18
Publishing country	United States
Document type	Journal Article
ISSN	2470-1343
ISSN (online)	2470-1343
DOI	10.1021/acsomega.1c03348
Database	MEDical Literature Analysis and Retrieval System OnLINE

Order via subito

Inter-library loan at ZB MED

Your chosen title can be delivered directly to ZB MED Cologne location if you are registered as a user at ZB MED Cologne.

Article ; Online: Development of superior antibodies against the S-protein of SARS-Cov-2 using macrocyclic epitopes

Hassan Traboulsi / Mohammed A. Khedr / Rafea Elgorashe / Yasair Al-Faiyz / Amr Negm

Arabian Journal of Chemistry, Vol 15, Iss 3, Pp 103631- (2022)

2022

Abstract	One of the proven methods to prevent and inhibit viral infections is to use antibodies to block the initial Receptor Binding Domain (RBD) of SARS-CoV-2 S protein and avoid its binding with the host cells. Thus, developing these RBD-targeting antibodies would be a promising approach for treating the SARS-CoV-2 infectious disease and stop virus replication. Macrocyclic epitopes constitute closer mimics of the receptor's actual topology and, as such, are expected to be superior epitopes for antibody generation. This work demonstrated the vital effect of the three-dimensional shape of epitopes on the developed antibodies' activity against RBD protein of SARS-CoV-2. The molecular dynamics studies showed the greater stability of the cyclic epitopes in comparison with the linear counterpart, which was reflected in the activity of their produced antibodies. Indeed, the antibodies we developed using macrocyclic epitopes showed superiority with respect to binding to RBD proteins compared to antibodies formed from a linear peptide. The results of the present work constitute a roadmap for developing superior antibodies that could be used to inhibit the activity of the SARS-CoV-2 and prevent its reproduction.
Keywords	SARS-CoV-2 ; Spike protein ; Receptor binding domain ; Epitopes ; Macrocyclic peptides ; Molecular dynamics ; Chemistry ; QD1-999
Subject code	570
Language	English
Publishing date	2022-03-01T00:00:00Z
Publisher	Elsevier
Document type	Article ; Online
Database	BASE - Bielefeld Academic Search Engine (life sciences selection)

Full text online

Full text

Inter-library loan at ZB MED

Your chosen title can be delivered directly to ZB MED Cologne location if you are registered as a user at ZB MED Cologne.

Article ; Online: SARS-CoV-2 Receptor Binding Domain as a Stable-Potential Target for SARS-CoV-2 Detection by Surface-Enhanced Raman Spectroscopy.

Awada, Chawki / Abdullah, Mohammed Mahfoudh Ba / Traboulsi, Hassan / Dab, Chahinez / Alshoaibi, Adil

Sensors (Basel, Switzerland)

2021 Volume 21, Issue 13

Abstract: In this work, we report a new approach for detecting SARS-CoV-2 RBD protein (RBD) using the surface-enhanced Raman spectroscopy (SERS) technique. The optical enhancement was obtained thanks to the preparation of nanostructured Ag/Au substrates. ... ...

Abstract	In this work, we report a new approach for detecting SARS-CoV-2 RBD protein (RBD) using the surface-enhanced Raman spectroscopy (SERS) technique. The optical enhancement was obtained thanks to the preparation of nanostructured Ag/Au substrates. Fabricated Au/Ag nanostructures were used in the SERS experiment for RBD protein detection. SERS substrates show higher capabilities and sensitivity to detect RBD protein in a short time (3 s) and with very low power. We were able to push the detection limit of proteins to a single protein detection level of 1 pM. The latter is equivalent to 1 fM as a detection limit of viruses. Additionally, we have shown that the SERS technique was useful to figure out the presence of RBD protein on antibody functionalized substrates. In this case, the SERS detection was based on protein-antibody recognition, which led to shifts in the Raman peaks and allowed signal discrimination between RBD and other targets such as Bovine serum albumin (BSA) protein. A perfect agreement between a 3D simulated model based on finite element method and experiment was reported confirming the SERS frequency shift potential for trace proteins detection. Our results could open the way to develop a new prototype based on SERS sensitivity and selectivity for rapid detection at a very low concentration of virus and even at a single protein level.
MeSH term(s)	Animals ; COVID-19 ; Cattle ; Gold ; Humans ; Metal Nanoparticles ; Nanostructures ; SARS-CoV-2 ; Serum Albumin, Bovine ; Spectrum Analysis, Raman
Chemical Substances	Serum Albumin, Bovine (27432CM55Q) ; Gold (7440-57-5)
Language	English
Publishing date	2021-07-05
Publishing country	Switzerland
Document type	Journal Article
ZDB-ID	2052857-7
ISSN	1424-8220 ; 1424-8220
ISSN (online)	1424-8220
ISSN	1424-8220
DOI	10.3390/s21134617
Database	MEDical Literature Analysis and Retrieval System OnLINE

Order via subito

To top

More links

Kategorien

Order via subito

More links

Kategorien

Order via subito

More links

Kategorien

Order via subito

Inter-library loan at ZB MED

Full text online

More links

Kategorien

Inter-library loan at ZB MED

More links

Kategorien

Order via subito

Full text online

More links

Kategorien

Inter-library loan at ZB MED

More links

Kategorien

Order via subito

Inter-library loan at ZB MED

More links

Kategorien

Order via subito

Inter-library loan at ZB MED

Full text online

More links

Kategorien

Inter-library loan at ZB MED

More links

Kategorien

Order via subito