Comparative toxicity assessment of CeO2 and ZnO nanoparticles towards Sinorhizobium meliloti, a symbiotic alfalfa associated bacterium: Use of advanced microscopic and spectroscopic techniques

Background: In the current era, development of molecular techniques involves nanotechniques and the synthesis of nanoparticles is considered as the preferred field in nanotechnology. Objective: The aim of the present work is to analyze the anticancer activity of the thymoquinone conjugated ZnO nanoparticles and to understand its mechanism of action in triple negative breast cancer cell line MDA-MB-231. Methods: Zinc Oxide (ZnO) nanoparticles have extensive applications and it was synthesized using a chemical precipitation method. Thymoquinone (TQ) is the major bioactive component of the seeds of Nigella sativa. Synthesized nanoparticles were characterized using various spectroscopic techniques. Thymoquinone coated nanoparticles were checked for its efficiency. The cytotoxicity of ZnO, TQ and TQ conjugated ZnO nanoparticles against MDA-MB-231. Colony forming and cell migration assay were performed to measure the proliferative competence of the breast cancer cells on exposure to nanoparticles. The mechanism of apoptosis was probed by assessing MMP, interplay between ER stress and ROS. Results: The results of the characterization techniques confirmed the particles synthesized were ZnO and TQ-ZnO nanoparticles. pH dependent release of the compound was observed. Anti-proliferative effect that impairs the formation of colony was found to be enhanced in cells exposed to combined treatment with the nanoconjugate. Conclusion: Hence, the TQ conjugated ZnO nanoparticles can act as an efficient carrier for drug delivery at the target site in TNBC cells.

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A Comparative Toxicity Assessment of Materials Used in Aquatic Construction

Archives of Environmental Contamination and Toxicology ◽

10.1007/s00244-010-9631-1 ◽

2011 ◽

Vol 61 (3) ◽

pp. 368-375 ◽

Cited By ~ 4

Author(s):

Benoit A. Lalonde ◽

William Ernst ◽

Gary Julien ◽

Paula Jackman ◽

Ken Doe ◽

...

Keyword(s):

Toxicity Assessment ◽

Comparative Toxicity ◽

Materials Used

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Comparative toxicity assessment of novel Si quantum dots and their traditional Cd-based counterparts using bacteria models Shewanella oneidensis and Bacillus subtilis

Environmental Science Nano ◽

10.1039/c8en00332g ◽

2018 ◽

Vol 5 (8) ◽

pp. 1890-1901 ◽

Cited By ~ 15

Author(s):

Sunipa Pramanik ◽

Samantha K. E. Hill ◽

Bo Zhi ◽

Natalie V. Hudson-Smith ◽

Jeslin J. Wu ◽

...

Keyword(s):

Quantum Dots ◽

Bacillus Subtilis ◽

Shewanella Oneidensis ◽

Toxicity Assessment ◽

Bacterial Cells ◽

Environment Friendly ◽

Comparative Toxicity ◽

Si Quantum Dots

The investigated Si quantum dots do not affect the viability of bacterial cells, and could potentially prove to be a more environment-friendly, sustainable, and cheaper alternative to traditional Cd-based quantum dots.

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Synthesis, characterization and evaluation of biological activities of manganese-doped zinc oxide nanoparticles

Tropical Journal of Pharmaceutical Research ◽

10.4314/tjpr.v16i10.4 ◽

2017 ◽

Vol 16 (10) ◽

pp. 2331-2339 ◽

Cited By ~ 6

Author(s):

Shakeel Ahmad Khan ◽

Sammia Shahid ◽

Waqas Bashir ◽

Sadia Kanwal ◽

Ahsan Iqbal

Keyword(s):

Zinc Oxide ◽

Band Gap ◽

Zno Nanoparticles ◽

Butylated Hydroxytoluene ◽

Total Phenolic ◽

Spectroscopic Techniques ◽

Antioxidant Power ◽

X Ray ◽

Doped Zno ◽

Mn Doped

Purpose: To synthesize, characterize and investigate the antimicrobial properties of pure and manganese-doped zinc oxide nanoparticles.Method: Un-doped and manganese-doped zinc oxide (Mn-doped ZnO) nanoparticles were prepared using co-precipitation method. The synthesized Mn-doped ZnO nanoparticles were characterized using energy-dispersive x-ray spectroscopy (EDX), scanning electron microscopy (SEM), and x-ray diffraction (XRD) spectroscopic techniques. Their band gap energies were measured with ultraviolet-visible (UVVis) spectroscopy, while their antioxidant properties were evaluated by ferric reducing antioxidant power (FRAP), DPPH radical-scavenging, ferric thiocyanate (FTC) and total phenolic content (TPC) assays. The antimicrobial activities of the nanoparticles against different bacterial strains were determined using agar diffusion method.Result: Results from XRD, SEM, EDX and UV-Vis analyses demonstrated successful synthesis of undoped and Mn-doped ZnO nanoparticles as seen in their hexagonal, wurtzite structures. The un-doped and Mn-doped ZnO nanoparticles had average grain sizes of 16.72 nm and 17.5 nm, and band gap energies of 3.585 eV and 2.737 eV, respectively. Significant antibacterial activity was manifested by Mndoped ZnO against E. coli, S. aureus, Klebsiella and B. subtilis, with zones of inhibition (ZOIs) of 13 ± 0.09 mm, 14 ± 0.01 mm, 18 ± 0.07 mm and 20 ± 0.10 mm, respectively. The Mn-doped ZnO nanoparticles also exhibited effective and significant antioxidant potential relative to butylated hydroxytoluene (BHT) and un-doped ZnO nanoparticles.Conclusion: Mn-doped ZnO nanoparticles demonstrate significant antimicrobial and antioxidant activities. Thus, the preparation is a good candidate for further development into therapeutic formulations.Keywords: Mn-doped ZnO, Nanoparticles, Properties, Antioxidant, Antibacterial

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BR96-Doxorubicin Conjugate (BMS-182248) Versus Doxorubicin: A Comparative Toxicity Assessment in Rats

Toxicologic Pathology ◽

10.1177/019262339402200502 ◽

1994 ◽

Vol 22 (5) ◽

pp. 473-488 ◽

Cited By ~ 17

Author(s):

Charles R. Comereski ◽

W. Michael Peden ◽

Thomas J. Davidson ◽

Garvin L. Warner ◽

Robert S. Hirth ◽

...

Keyword(s):

Toxicity Assessment ◽

Comparative Toxicity

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Studies on birefringence, order parameter and image analysis of liquid crystalline p-n butyloxy/butyl benzoic acid with dispersed ZnO nanoparticles

Zeitschrift für Naturforschung A ◽

10.1515/zna-2020-0198 ◽

2020 ◽

Vol 0 (0) ◽

Author(s):

P. Jayaprada ◽

P. Pardhasaradhi ◽

B. T. P. Madhav ◽

K. Krishna Reddy ◽

D. Rama Sekhara Reddy ◽

...

Keyword(s):

Zno Nanoparticles ◽

Order Parameter ◽

Liquid Crystalline ◽

Refractive Indices ◽

Optical Parameters ◽

Spectroscopic Techniques ◽

Zno Nps ◽

Scanning Calorimetry ◽

Geometry Model ◽

Wide Range

AbstractZnO nanoparticles (nps) have wide range of applications and improve the optical parameters of molecules of soft liquid crystalline (LC) materials. The present paper mainly discusses the optical studies on LC materials regarding p-n-butyloxybenzoic acid (4oba) and p-n-butylbenzoic (4ba) compound along with homogeneous dispersion of ZnO nps in lower weight concentration, i.e., 1, 1.5, 2 and 2.5 wt%. The existence and size of ZnO nps in LC compounds are well determined through spectroscopic techniques such as scanning electron microscopy (SEM) and X-ray diffraction (XRD). The temperatures of LC compounds and phase transitions are determined by using polarizing optical microscopy (POM) and differential scanning calorimetry (DSC) which is found to decrease with increasing concentration of dispersed ZnO nps. Image enhancement with visual quality matrix method is used to improve the quality of the image. Specially designed wedge-shaped modified spectrometer is used to determine the refractive indices with different wavelengths (460, 500, 570 and 635 nm). The refractive indices measured are fitted with two and three coefficient Cauchy model. Further, the order parameter S of the molecules of 4ba and 4oba with dispersed ZnO nps are determined by molecular field models namely Kuczynski, Vuks and effective geometry model, respectively. From the data, it is found that the values of birefringence (δn) and order parameter (S) of the molecules of 4oba and 4ba are enhanced with the dispersion of ZnO nps with increasing weight concentrations in the stabilized nematic thermal region.

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Composition and molar mass characterisation of bacterial extracellular polymeric substances by using chemical, spectroscopic and fractionation techniques

Environmental Chemistry ◽

10.1071/en10119 ◽

2011 ◽

Vol 8 (2) ◽

pp. 155 ◽

Cited By ~ 10

Author(s):

Enrica Alasonati ◽

Vera I. Slaveykova

Keyword(s):

Chemical Composition ◽

Mass Distribution ◽

Sinorhizobium Meliloti ◽

Extracellular Polymeric Substances ◽

Molar Mass ◽

Waste Water Treatment ◽

Molar Mass Distribution ◽

Spectroscopic Techniques ◽

High Molar Mass ◽

Vis Spectroscopy

Environmental contextExtracellular polymeric substances (EPS) released by microorganisms are an important component of organic matter in the environment. EPS play an essential role in cell adhesion to surfaces, biofilm and floc formation, soil aggregation and stability and in the activated sludge of waste water treatment plants. EPS are complex mixtures containing components of different chemical nature and molecular size, which make their characterisation difficult. The present work explores the link between chemical composition and molar-mass distribution of the EPS released by the bacterium Sinorhizobium meliloti by using a combination of chemical, spectroscopic and fractionation techniques. AbstractThe chemical composition and molar-mass distribution of extracellular polymeric substances (EPS) produced by the bacterium Sinorhizobium meliloti have been characterised by combining asymmetrical flow field-flow fractionation (AFlFFF), chemical and spectroscopic techniques. The relationship between the EPS composition and molar-mass distribution has been studied by comparing the characteristics of EPS excreted by the wild type S. meliloti and by a mutant deficient in the production of high-molar-mass EPS, as well as by the analysis of total protein content in the collected AFlFFF fractions. Total organic carbon, protein and polysaccharide contents of the EPS were also determined. Obtained results demonstrate the existence of two major populations with weight-average molar masses of 1.40 × 105 and 4.57 × 105 g mol–1 respectively. The lower molar-mass population contained predominantly protein-like substances, detectable by UV-VIS spectroscopy, whereas the higher molar-mass population was rich in exopolysaccharides and exoproteins. These findings are in general agreement with the size distributions and chemical heterogeneity observed by nanoparticle tracking analysis, and the characterisation of the composition of all the EPS by different analytical techniques.

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