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Adsorption of ciprofloxacin from aqueous environment by using synthesized nanoceria

Rahdar Abbas, Rahdar Somayeh, Ahmadi Shahin, Fu Jie

Ecological Chemistry and Engineering. S

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2019

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Vol. 26, nr 2

299--311

EN

Antibiotics are widely detected emerging contaminants in water environments and possess high potential risks to human health and aquatic life. However, conventional water treatment processes cannot remove them sufficiently. To develop innovative nanoadsorbents for effectively remove antibiotic contaminants from water environment, nanoceria were prepared via in situ precipitation method, and evaluated their adsorption capacity for a model antibiotic, ciprofloxacin (CIP). The properties of the prepared nanoceria were characterized by transmission electron microscopy (TEM), X-ray diffraction (XRD) and vibration sample magnetization (VSM). The effect of various operating parameters such as pH, initial CIP concentration, contact time, and adsorbent dosage on adsorptions of CIP were studied in batch experiments. Maximum adsorption capacity of the nanoceria was 49.38 mg/g at the conditions of pH 5, initial CIP concentration of 200 mg/dm3 and adsorbent dosage of 0.2 g/dm3, when 95.43 % of the CIP was removed. For adsorption kinetics, both pseudo-first-order and pseudo-second-order models can well describe the experimental data, indicating that the adsorption process was controlled by both physical diffusion and chemical interaction. For adsorption isotherms, the Freundlich model could fit the experimental data better than the Langmuir and Temkin models, suggesting a multilayer adsorption process. The thermal dynamics study showed the absorption process was spontaneity, exothermic, and irreversible. Finally it was concluded that the nanoceria can be used effectively for CIP removal.

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Ultrasound assisted green synthesis of cerium oxide nanoparticles using Prosopis juliflora leaf extract and their structural, optical and antibacterial properties

Arunachalam T., Karpagasundaram U., Rajarathinam N.

Materials Science Poland

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2017

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Vol. 35, No. 4

791--798

EN

Cerium oxide nanoparticles (CONPs) were prepared using ultrasound assisted leaf extract of Prosopis juliflora acting as a reducing as well as stabilizing agent. The synthesized CONPs were characterized by ultraviolet-visible absorption spectroscopy (UV-Vis), particle size analyzer (PSA), Fourier transform infrared spectroscopy (FT-IR), Raman spectroscopy, X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS) and high-resolution transmission electron microscopy (HRTEM). From the UV-Vis analysis, the optical band gap of the prepared CONPs (Eg = 3.62 eV) was slightly increased as compared to the bulk ceria (E g = 3.19 eV). The phytochemicals in the extract reduced the particle size to 3.7 nm ± 0.3 nm, as it is evident from the PSA. FT-IR results confirmed the Ce-O stretching bands by showing the peaks at 452 cm-1. The Raman spectrum showed a characteristic peak shift for CONPs at 461.2 cm-1. XRD analysis revealed the cubic fluorite structure of the synthesized nanoparticles with the lattice constant, a of 5.415 Å and unit cell volume, V of 158.813 Å3. XPS signals were used to determine the concentration of Ce3+ and Ce4+ in the prepared CONPs and it was found that major amount of cerium exist in the Ce4+ state. HRTEM images showed spherical shaped particles with an average size of 15 nm. Furthermore, the antibacterial activity of the prepared CONPs was evaluated and their efficacies were compared with the conventional antibiotics using disc diffusion assay against a set of Gram positive (G+) bacteria (Staphylococcus aureus, Streptococcus pneumonia) and Gram negative (G-) bacteria (Pseudomonas aeruginosa, Proteus vulgaris). The results suggested that CONPs showed antibacterial activity with significant variations due to the differences in the membrane structure and cell wall composition among the two groups tested.

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Ocena cytotoksycznego działania nanocząstek tlenku ceru

Zapór L.

Inżynieria i Aparatura Chemiczna

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2014

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Nr 4

326--327

PL

Nanometryczny tlenek ceru z uwagi na szerokie zastosowanie wymaga oceny toksykologicznej. W pracy oceniano cytotoksyczne działanie nanocząstek tlenku ceru (< 25 nm) na komórki układu oddechowego (A549) i rozrodczego (CHO-9). Wykazano, że nanotlenek ceru może działać cytotoksycznie powodując zaburzenia metabolizmu komórkowego i zmiany w przepuszczalności błon komórkowych. Wartości dawek cytotoksycznych wynosiły 30÷200 μg/cm3 w zależności od rodzaju komórek oraz badanego efektu toksycznego.

EN

Cerium oxide nanoparticles (nanoceria) require the toxicological evaluation due to their wide application. The cytotoxic action of cerium oxide nanoparticles (< 25 nm) on cells of the respiratory (A549) and reproductive (CHO-9) systems were investigated. It was shown that nanoceria exhibited cytotoxic effects causing cellular metabolism disturbances and changes in the permeability of cell membranes. Cytotoxicity doses were equal to 30÷200μg/cm3 depending on a kind of cells and cytotoxicity endpoint.