Electronic and optical properties of 5-AVA-functionalized BN nanoclusters: A DFT study

We carried out detailed density functional theory (DFT) and time-dependent density functional theory (TD-DFT) calculations upon 5-aminolevulinic acid-functionalized B12N12 and B16N16 nanoclusters with the B3LYP, B3PW91, and PBE methods using the 6-311+G∗∗ basis set. The calculated adsorption energies of 5-aminolevulinic acid with the BN nanoclusters were evaluated at T = 298.15 and 311.15 K in the gaseous and aqueous environments with the B3LYP, B3PW91, and PBE methods. Our results showed that the adsorption of the 5-AVA molecule (NH2 group) with B12N12 is more favorable than-with the B16N16 nanocluster in the gas and solvent phases. It is anticipated that a 5-aminolevulinic acid (5-AVA) drug incorporating BN clusters could find application in drug delivery systems and in biomedical devices. © The Royal Society of Chemistry and the Centre National de la Recherche Scientifique 2016

A DFT study of 5-fluorouracil adsorption on the pure and doped BN nanotubes

Abstract The electronic and adsorption properties of the pristine, Al-, Ga-, and Ge-doped BN nanotubes interacted with 5-fluorouracil molecule (5-FU) were theoretically investigated in the gas phase using the B3LYP density functional theory (DFT) calculations. It was found that the adsorption behavior of 5FU molecule on the pristine (8, 0) and (5, 5) BNNTs are electrostatic in nature. In contrast, the 5FU molecule (O-side) implies strong adsorption on the metal-doped BNNTs. Our results indicate that the Ga-doped presents high sensitivity and strong adsorption with the 5-FU molecule than the Al- and Ge-doped BNNTs. Therefore, it can be introduced as a carrier for drug delivery applications. © 2015 Elsevier Ltd

Antibacterial and Antioxidant Activities and Phytochemical Properties of Punica granatum Flowers in Iran

The antioxidant and antibacterial activities in the ethanol extract of pomegranate flowers were evaluated and used in the present study. Antioxidant activities were studied by 1,1-diphenyl-2-picrylhydrazyl (DPPH), reducing power, total antioxidant capacity methods. The total phenolic contents of flower were analyzed by Folin–Ciocalteu methods. Antimicrobial activities of hydroalcoholic extracts of valid against 8 antibiotic-resistant Gram-negative and Gram-positive bacterial strains including two species of Escherichia coli, Staphylococcus aureus, Staphylococcus epidermidis, Pseudomonas aeruginosa, Enterococcus faecalis, Klebsiella pneumonia and Shigella spp. were investigated. The extract was primarily screened for their possible antibacterial effects using disc diffusion methods. The antioxidant activity of extraction was investigated, including the scavenging activity of 2,2-diphenyl-1-picrylhydrazyl (DPPH) radicals (27.92 μg ml−1 as EC50 value), the total phenolic contents (40.8 ± 1.3 mg gallic acid equivalent g−1 of extract), total flavonoid contents (64 ± 38 mg quercetin equivalent g l−1 of extract), and reducing power there were significant differences between extract and BHT (P < 0.05). The potential antibacterial activities at different concentrations of the extract were elucidated. The extract displayed variable degrees of antibacterial activities on different bacteria and the highest amount of total phenol and also a significant antioxidant activity. © 2018, Shiraz University

Adsorption of Celecoxib on B12N12 fullerene: Spectroscopic and DFT/TD-DFT study

In this study, we evaluated the effect of the Celecoxib (CXB) adsorption on the electronic and optical properties of B12N12 fullerene by using density functional theory (DFT) and time-dependent density functional theory (TD-DFT) calculations with the M06-2X functional and the 6-311+G** basis set. The calculated adsorption energies of CXB with the B12N12 fullerene was evaluated at T = 298.15 K in the vacuum and solvent (water) environments with the M06-2X functional. UV absorption and IR spectra were calculated and studied in order to identify the most important changes happening as a consequence of interactions between CXB and B12N12 fullerene. The results revealed that the adsorption of the CXB molecule from its NH2 head on the B12N12 is more favorable than those of the SO2 and NH groups in the gas and solvent environments. It is anticipated that the applied B12N12 fullerene could be suitable as a biomedical carrier for the delivery of CXB drug. © 201

Ga-doped and antisite double defects enhance the sensitivity of boron nitride nanotubes towards Soman and Chlorosoman

Adsorption of Soman and Chlorosoman over the outer surface of boron nitride nanotube (BNNT) was studied using density functional theory (DFT) calculations to consider its sensitivity toward mentioned nerve agents. Then, we studied the sensitivity of Ga-doped BNNT and double-antisite defective BNNT (d-BNNT) effects towards adsorbed molecule resulting in eye-catching sensitivity of defected adsorbents representing strong chemical adsorption on the Ga-doped BNNT, while they are mainly physisorbed on the pure BNNT with negligible electronic properties. Density of states (DOSs) was analyzed for further understanding of electronic properties of the applied configurations. Charges were moved from BNNT to the single molecules while in case of Ga-doped and d-BNNT; the charges were transferred from single molecules to the defected adsorbents. These along with outcomes of quantum molecular descriptors, difference in energy gap (Eg), and dipole moments clearly reveal that the d-BNNT is a promising sensor material for the detection of these nerve agents. © 2017 Elsevier B.V

Preparation, characterization and toxicity evaluation of Co3O4 and NiO-filled multi-walled carbon nanotubes loaded to chitosan

Multi-walled Carbon nanotubes (MWCNTs) have been extensively explored for a variety of biomedical and tissue engineering applications. Their high surface area provides tunable multiple attachment sites for acquiring appropriate biological and biomechanical properties. Despite, the cytotoxicity of MWCNTs is dubious with or without surface functionalization. In the present study, two different kinds of multi-walled carbon nanotubes (MWCNTs) in the presence of cobalt oxide (Co3O4) and nickel oxide (NiO) nanoparticles have been prepared through a simplistic and effective method, and thus, the Co3O4/MWNT and NiO/MWNT structures are loaded to chitosan in methanol solution at 65°C. Results upon the synthesis and structural characterization were obtained by Fourier transform infrared (FT-IR) spectroscopy, X-ray diffraction (XRD), and transmission electron microscopy (TEM), respectively. It has been shown that the tuned functionalized MWCNTs are able to reduce cytotoxic effects and improve biocompatibility and be more appropriate for potential future clinical applications. © 2017 Elsevier B.V

Synthesis and Antibacterial Activities of Novel Hg(II) and Zn(II) Complexes of Bis(Thiosemicarbazone) Acenaphthenequinone Loaded to MWCNTs

This paper describes a series of new polyamides containing bis(thiosemicarbazone) acenaphthenequinone (PA), bis(thiosemicarbazone) acenaphthenequinone zinc (Z-PA), and bis(thiosemicarbazone) acenaphthenequinone mercury (H-PA) complexes loaded onto MWCNTs synthesized via a chemical precipitation method in methanol followed by antimicrobial activity studies on the novel functionalized MWCNTs complexes. These complexes are characterized by FT-IR spectroscopy, powder X-ray diffraction (XRD), scanning electron microscopy (SEM), and transmission electron microscopy (TEM). The antibacterial activity of free PA, Z-PA, and H-PA complexes loaded onto MWCNTs are studied against gram-positive and gram-negative bacteria. The results indicate that the HPA/MWCNT complex is the most effective growth inhibitor against Listeria monocytogenes and Pseudomonas aeruginosa, exhibiting the potential for the use as an antibacterial agent. © 2019, Pleiades Publishing, Ltd