Selenium nanoparticles synthesized using an eco-friendly method: Dye decolorization from aqueous solutions, cell viability, antioxidant, and antibacterial effectiveness

International audienceSelenium nanoparticles (SeNPs) were fabricated using a green microwave technique in the presence of ascorbic acid. The morphological features indicated that the semi-spherical SeNPs with a diameter 8.5-22nm were configured in agglomerated spherical shapes with diameters around 0.47-0.71 μm. Furthermore, the removal of Fuchsin Basic dye from aqueous solutions was investigated upon variation of concentration of SeNPs. The degradation efficiency achieved 100 % for 10 mg of SeNPs after 34 min of visible light irradiation time. The antioxidant activity 2 was tested via DPPH radical scavenging assay and displayed that the highest scavenging capacity (311.115.72 mg/g) was achieved by SeNPs at a concentration of 106.25 mg/mL. Otherwise, the cell viability of SeNPs through human fibroblasts cell lines in-vitro was reduced to be 75.13.8 % with nanoparticle concentration around 500 μg/mL. The antibacterial activity was investigated against gram-negative and gram-positive bacteria such as Escherichia coli (E.coli), Pseudomonas aeruginosa (P. aeruginosa), Klebsiella pneumoniae (K. pneumonia), Staphylococcus aureus (S. aureus), and Bacillus subtilis (B. subtilis) bacteria after one day of exposure. It was illustrated that SeNPs did not display an activity towards Staphylococcus aureus, while it possessed the highest one against Escherichia coli with MBC of 50 ± 1.76 g/mL compared with 26 ± 0.6 g/mL for the standard antibiotic. These tremendous properties of SeNPs indicate that manipulating multifunctional nanoparticles for versatile wound and skin treatment applications is highly encouraging

Outstanding Graphene Quantum Dots from Carbon Source for Biomedical and Corrosion Inhibition Applications: A Review

Graphene quantum dots (GQD) is an efficient nanomaterial composed of one or more layers of graphene with unique properties that combine both graphene and carbon dots (CDs). It can be synthesized using carbon-rich materials as precursors, such as graphite, macromolecules polysaccharides, and fullerene. This contribution emphasizes the utilization of GQD-based materials in the fields of sensing, bioimaging, energy storage, and corrosion inhibitors. Inspired by these numerous applications, various synthetic approaches have been developed to design and fabricate GQD, particularly bottom-up and top-down processes. In this context, the prime goal of this review is to emphasize possible eco-friendly and sustainable methodologies that have been successfully employed in the fabrication of GQDs. Furthermore, the fundamental and experimental aspects associated with GQDs such as possible mechanisms, the impact of size, surface alteration, and doping with other elements, together with their technological and industrial applications have been envisaged. Till now, understanding simple photo luminance (PL) operations in GQDs is very critical as well as there are various methods derived from the optical properties of manufactured GQDs can differ. Lack of determining exact size and morphology is highly required without loss of their optical features. Finally, GQDs are promising candidates in the after-mentioned application fields

Electrospun nanofibrous scaffolds of ε-polycaprolactone containing graphene oxide and encapsulated with magnetite nanoparticles for wound healing utilizations

Wound healing treatment with a nanofibrous matrix is a serious demand to avoid associated complications, including bacterial infections. Magnetite nanoparticles (MNPs) were encapsulated into electrospun nanofibrous scaffolds of ε -polycaprolactone (PCL) containing graphene oxide (GO) nanosheets. The structural and morphological behaviors of the obtained scaffolds were investigated. The modification of nanofibers via the addition of MNPs generated a slight change of morphology, whereas the fibers’ diameters were around 0.2–0.5, 0.1–0.3, 0.1–0.2, and 0.1–0.3 μ m for 0.0NPs-GO@PCL, 0.1NPs-GO@PCL, 0.2NPs-GO@PCL, and 0.3NPs-GO@PCL, respectively. Moreover, the roughness average (Ra) increased from 119 nm to be about 169 nm from the lowest and the highest contributions of MNPs. The Human fibroblasts cell line (HFB4) reached around 98.4 ± 3.1% cell viability for 0.2MNPs-GO@PCL composition. The antibacterial activity of the highest contribution of MNPs reached about 11.4 ± 1.6 mm and 12.3 ± 1.2 mm against S. aureus and E. coli , respectively. The in-vitro cells’ attachment of HFB4 showed that cells were adhered to and proliferated through the nanofibrous scaffolds. Cells also spread and grew significantly as the modification via MNPs. Thus, indicating that designing of new scaffold for wound healing and disinfection utilization could be reached via tailoring of electrospun products encapsulating with biocompatible substances such as graphene oxide and magnetite

A Study of the Synthesis and Characterization of New Acrylamide Derivatives for Use as Corrosion Inhibitors in Nitric Acid Solutions of Copper

The objective of this research was to explore the impact of corrosion inhibition of some synthetic acrylamide derivatives 2-cyano-N-(4-hydroxyphenyl)-3-(4-methoxyphenyl)acrylamide (ACR-2) and 2-cyano-N-(4-hydroxyphenyl)-3-phenylacrylamide (ACR-3) on copper in 1.0 M nitric acid solution using chemical and electrochemical methods, including mass loss as a chemical method and electrochemical impedance spectroscopy (EIS) and potentiodynamic polarization (PP) as electrochemical methods. By Fourier-transform infrared spectroscopy (FTIR), proton nuclear magnetic resonance (1HNMR), and mass spectroscopy (MS) methods, the two compounds were verified and characterized. There is evidence that both compounds were effective corrosion inhibitors for copper in 1.0 M nitric acid (HNO3) solutions, as indicated by the PP curves, which show that these compounds may be considered mixed-type inhibitors. With the two compounds added, the value of the double-layer capacitance was reduced. In the case of 20 × 10−5 M, they reached maximum efficiencies of 84.5% and 86.1%, respectively. Having studied its behavior during adsorption on copper, it was concluded that it follows chemical adsorption and Langmuir isotherm. The theoretical computations and the experimental findings were compared using density functional theory (DFT) and Monte Carlo simulations (MC)