scholarly journals The assisting-approach of horseradish peroxidase immobilized onto amine-functionalized superparamagnetic iron oxide nanoparticles as a biocatalyst

2021 ◽  
Author(s):  
Basem E. Keshta ◽  
Ali H. Gemeay ◽  
Abeer A. Khamis
Keyword(s):  
Electron Microscopy ◽  
Iron Oxide ◽  
Horseradish Peroxidase ◽  
Oxidative Degradation ◽  
Activation Parameters ◽  
Superparamagnetic Iron Oxide ◽  
Nitrogen Adsorption ◽  
X Ray ◽  
Amine Functionalized ◽  
Catalytic Experiment

Abstract To enhance the removal of dye, horseradish peroxidase (HRP) was immobilized onto amine-functionalized superparamagnetic iron oxide and used as a biocatalyst for the oxidative degradation of Acid black-HC dye. The anchored enzyme was characterized by sets of techniques such as vibrating sample magnetometer, Fourier transform infrared, X-ray diffraction, thermogravimetric, scanning electron microscopy, BET and BJH methods, nitrogen adsorption-desorption measurements , Zeta potential, energy dispersive X-ray (EDX), and transmission electron microscopy. The Michaelis constant (K m ) values of free peroxidase and immobilized horseradish peroxidase were determined that equal 4.5 and 5 mM for hydrogen peroxide; 12.5 and 10 mM for guaiacol, respectively. Besides, the free peroxidase is thermally stable at 40°C however, the immobilized enzyme was up to 60°C. In the catalytic experiment, the immobilized HRP showed superior catalytic activity compared with free HRP for the oxidative decolorization and removal of Acid black-HC dye. The impacts of experimental parameters for instance catalyst dosage, pH, H 2 O 2 concentration, and temperature, were investigated. The reaction followed second-order kinetics and the thermodynamic activation parameters were determined.

scholarly journals Reversible magnetism switching of iron oxide nanoparticle dispersions by controlled agglomeration

2021 ◽  
Author(s):  
Stephan Müssig ◽  
Björn Kuttich ◽  
Florian Fidler ◽  
Daniel Haddad ◽  
Susanne Wintzheimer ◽  
...  
Keyword(s):  
Magnetic Properties ◽  
Iron Oxide ◽  
Light Scattering ◽  
Superparamagnetic Iron Oxide ◽  
Iron Oxide Nanoparticle ◽  
Oxide Nanoparticles ◽  
X Ray ◽  
X Ray Scattering ◽  
Nanoparticle Dispersions ◽  
Oxide Nanoparticle

The controlled agglomeration of superparamagnetic iron oxide nanoparticles (SPIONs) was used to rapidly switch their magnetic properties. Small-angle X-ray scattering (SAXS) and dynamic light scattering showed that tailored iron oxide...

scholarly journals Study of the Effect of TiO2 Layer on the Adsorption and Photocatalytic Activity of TiO2-MoS2 Heterostructures under Visible-Infrared Light

2020 ◽  
Vol 2020 ◽  
pp. 1-9 ◽  
Author(s):  
N. Cruz-González ◽  
O. Calzadilla ◽  
J. Roque ◽  
F. Chalé-Lara ◽  
J. K. Olarte ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Photocatalytic Activity ◽  
Photoelectron Spectroscopy ◽  
Diffuse Reflectance Spectroscopy ◽  
Nitrogen Adsorption ◽  
High Photocatalytic Activity ◽  
Infrared Light ◽  
Polluted Water ◽  
Light Spectrum ◽  
X Ray

In the last decade, the urgent need to environmental protection has promoted the development of new materials with potential applications to remediate air and polluted water. In this work, the effect of the TiO2 thin layer over MoS2 material in photocatalytic activity is reported. We prepared different heterostructures, using a combination of electrospinning, solvothermal, and spin-coating techniques. The properties of the samples were analyzed by scanning electron microscopy (SEM), transmission electron microscopy (TEM), atomic force microscopy (AFM), X-ray diffraction (XRD), nitrogen adsorption-desorption isotherms, UV-Vis diffuse reflectance spectroscopy (UV-Vis-DRS), and X-ray photoelectron spectroscopy (XPS). The adsorption and photocatalytic activity were evaluated by discoloration of rhodamine B solution. The TiO2-MoS2/TiO2 heterostructure presented three optical absorption edges at 1.3 eV, 2.28 eV, and 3.23 eV. The high adsorption capacity of MoS2 was eliminated with the addition of TiO2 thin film. The samples show high photocatalytic activity in the visible-IR light spectrum.

scholarly journals Additive-Free Rice Starch-Assisted Synthesis of Spherical Nanostructured Hematite for Degradation of Dye Contaminant

Nanomaterials ◽  
2018 ◽  
Vol 8 (9) ◽  
pp. 702 ◽  
Author(s):  
Juan Matmin ◽  
Irwan Affendi ◽  
Salizatul Ibrahim ◽  
Salasiah Endud
Keyword(s):  
Electron Microscopy ◽  
Diffuse Reflectance Spectroscopy ◽  
Volume Ratio ◽  
Rhombohedral Phase ◽  
Nitrogen Adsorption ◽  
Rice Starch ◽  
Blue Dye ◽  
Synthesis Methods ◽  
X Ray ◽  
Stabilizing Agents

Nanostructured hematite materials for advanced applications are conventionally prepared with the presence of additives, tainting its purity with remnants of copolymer surfactants, active chelating molecules, stabilizing agents, or co-precipitating salts. Thus, preparing nanostructured hematite via additive-free and green synthesis methods remains a huge hurdle. This study presents an environmentally friendly and facile synthesis of spherical nanostructured hematite (Sp-HNP) using rice starch-assisted synthesis. The physicochemical properties of the Sp-HNP were investigated by Fourier-transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), thermogravimetric analysis (TGA), field emission scanning electron microscopy (FESEM), energy dispersive X-ray spectroscopy (EDX), transmission electron microscopy (TEM), UV-Vis diffuse reflectance spectroscopy (DR UV-Vis), and nitrogen adsorption–desorption analysis. The Sp-HNP showed a well-crystallized structure of pure rhombohedral phase, having a spherical-shaped morphology from 24 to 48 nm, and a surface area of 20.04 m2/g. Moreover, the Sp-HNP exhibited enhanced photocatalytic degradation of methylene blue dye, owing to the large surface-to-volume ratio. The current work has provided a sustainable synthesis route to produce spherical nanostructured hematite without the use of any hazardous agents or toxic additives, in agreement with the principles of green chemistry for the degradation of dye contaminant.

Magnetic Properties of Ferrous Ferric Oxide Confined in Porous Silicon

2010 ◽  
Vol 663-665 ◽  
pp. 1142-1145
Author(s):  
Yuan Ming Huang ◽  
Bao Gai Zhai ◽  
Qing Lan Ma ◽  
Ming Meng
Keyword(s):  
Electron Microscopy ◽  
Magnetic Properties ◽  
Iron Oxide ◽  
Porous Silicon ◽  
Ferrous Iron ◽  
Silicon Film ◽  
X Ray ◽  
Loop Measurement ◽  
Scanning Electron

During the chemical synthesis nanometer-sized particles of ferrous iron oxide were in situ infiltrated into the mesopores in a porous silicon film. The microstructures of porous silicon and the magnetic properties of the nanometer-sized particles of the ferrous iron oxide were characterized with scanning electron microscopy, X-ray diffractometry, and the hysteresis loop measurement, respectively. Our results have demonstrated that the magnetic properties of the nanometer-sized Fe3O4 particles can be dramatically modified when they are confined into the mesopores of the porous silicon film.

scholarly journals Biosynthesis and Characterization of Iron Oxide Nanoparticles Synthesized using Earthworm Based Extracts

2018 ◽  
Vol 4 (4) ◽  
pp. 452-455
Author(s):  
P. Suganya ◽  
P.U. Mahalingam
Keyword(s):  
Electron Microscopy ◽  
Iron Oxide ◽  
Seed Germination ◽  
Eisenia Fetida ◽  
Fourier Transforms ◽  
Water Extract ◽  
Warm Water ◽  
Cow Dung ◽  
Fe2o3 Nanoparticles ◽  
X Ray

Iron oxide (β-Fe2O3) nanoparticles were synthesized through a biological method using earthworm based extracts like Eudrilus eugineae vermiwash, Eisenia fetida vermiwash, Eudrilus eugineae crushed extract, Eisenia fetida crushed extract, Eudrilus eugineae warm water extract, Eisenia fetida warm water extract and cow dung extract as a reducing and stabilizing agents. The development of β-Fe2O3 nanoparticles in the reaction mixture was determined by UV–visible spectroscopy. Followed by, the synthesized β-Fe2O3 nanoparticles were characterized by X-ray diffraction, Fourier transforms infra–red spectroscopy, scanning electron microscopy, and energy dispersive X-ray and transmission electron microscopy. Synthesized β-Fe2O3 NPs are characterized as crystalline structure of hexagonal shape with particle size of 2.08-94.37 nm and carrying unique functional groups. Bioefficiency of β-Fe2O3 was assessed through In-vitro seed germination study with green gram (Vigna radiata) and results revealed that 200 mg concentrations of α-Fe2O3 supported better seed germination and early growth in V. radiata.

Superparamagnetic iron oxide nanoparticles enhance glioma radiosensitivity via inducing cell cycle arrest and apoptosis

2020 ◽  
Author(s):  
Jinning Mao ◽  
Meng Jiang ◽  
Xingliang Dai ◽  
Guodong Liu ◽  
Zhixiang Zhuang ◽  
...  
Keyword(s):  
Cell Cycle ◽  
Iron Oxide ◽  
Iron Oxide Nanoparticles ◽  
Glioma Cells ◽  
Superparamagnetic Iron Oxide ◽  
Spherical Shape ◽  
Treated Group ◽  
Superparamagnetic Iron Oxide Nanoparticles ◽  
Oxide Nanoparticles ◽  
X Ray

Abstract Aim: Superparamagnetic iron oxide nanoparticles (SPIONs) is a widely used biomedical material for imaging and targeting drug delivery. We synthesized SPIONs and tested their effects on the radiosensitization of glioma.Methods: Acetylated 3-aminopropyltrimethoxysilane (APTS)-coated iron oxide nanoparticles (Fe3O4 NPs) were synthesized via a one-step hydrothermal approach and the surface was chemically modified with acetic anhydride to generate surface charge-neutralized NPs. NPs were characterized by TEM and ICP-AES. Radiosensitivity of U87MG glioma cells was evaluated by MTT assay. Cell cycle and apoptosis in glioma cells were examined by flow cytometry. Results: APTS-coated Fe3O4 NPs had a spherical or quasi-spherical shape with average size of 10.5±1.1 nm. NPs had excellent biocompatibility and intracellular uptake of NPs reached the peak 24 hours after treatment. U87 cell viability decreased significantly after treatment with both X-ray and NPs compared to X-ray treatment alone. Compared to X-ray treatment alone, the percentage of cells in G2/M phase (31.83%) significantly increased in APTS-coated Fe3O4 NPs plus X-ray treated group (P<0.05). In addition, the percentage of apoptotic cells was significant higher in APTS-coated Fe3O4 NPs plus X-ray treated group than in X-ray treatment alone group (P<0.05). Conclusion: APTS-coated Fe3O4 NPs achieved excellent biocompatibility and increased radiosensitivity for glioma cells.

Beta-Cyclodextrin-triggered fabrication of broccoli-like ZnO nanoaggregates with enhanced photocatalytic capability

2020 ◽  
Vol 13 (02) ◽  
pp. 2051004
Author(s):  
Jinyan Xiong ◽  
Wei Li ◽  
Kai Zhao ◽  
Weijie Li ◽  
Gang Cheng
Keyword(s):  
Electron Microscopy ◽  
Photoelectron Spectroscopy ◽  
Separation Efficiency ◽  
Nitrogen Adsorption ◽  
Electrochemical Measurement ◽  
X Ray ◽  
Recombination Efficiency ◽  
Beta Cyclodextrin ◽  
Composition And Structure ◽  
Pollution Removal

Nanocrystallite aggregates have great potential in semiconductor-based photocatalysis toward environmental pollution removal. In this work, we reported the fabrication of broccoli-like zinc oxide nanoaggregates in the presence of beta-cyclodextrin in ethylene glycol-H2O medium. The composition and structure of the as-obtained ZnO nanoaggregates were characterized by powder X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), scanning electron microscopy (SEM), transmission electron microscopy (TEM) and nitrogen adsorption. It was observed that the beta-cyclodextrin played an important role in the fabrication of such broccoli-like structure. A plausible formation mechanism was discussed on the basis of the controllable experiments. The photocatalytic performance of the products was studied through the photodegradation of rhodamine B under simulated sunlight irradiation. Compared to the spherical ZnO nanoaggregates and ZnO broken spheres, the broccoli-like ZnO exhibited superior photocatalytic efficiency. Based on the photocurrent and electrochemical measurement results, the higher separation efficiency of the photogenerated carriers and lower recombination efficiency of the photoinduced electron–hole pairs over the broccoli-like ZnO nanoaggregates contributed to their remarkable photocatalytic activity.

scholarly journals The Local Atomic Structure of Colloidal Superparamagnetic Iron Oxide Nanoparticles for Theranostics in Oncology

Biomedicines ◽  
2018 ◽  
Vol 6 (3) ◽  
pp. 78 ◽  
Author(s):  
Elena Kuchma ◽  
Stanislav Kubrin ◽  
Alexander Soldatov
Keyword(s):  
Iron Oxide ◽  
Atomic Structure ◽  
Superparamagnetic Iron Oxide ◽  
Local Atomic Structure ◽  
Superparamagnetic Nanoparticles ◽  
Characterization Methods ◽  
X Ray ◽  
Magnetic Structures ◽  
Radiation Sources ◽  
X Ray Absorption

The paper contains an overview of modern spectroscopic methods for studying the local atomic structure of superparamagnetic nanoparticles based on iron oxide (SPIONs), which are an important class of materials promising for theranostics in oncology. Practically important properties of small and ultra small nanoparticles are determined primarily by their shape, size, and features of the local atomic, electronic, and magnetic structures, for the study of which the standard characterization methods developed for macroscopic materials are not optimal. The paper analyzes results of the studies of SPIONs local atomic structure carried out by X-ray absorption spectroscopy at synchrotron radiation sources and Mössbauer spectroscopy during the last decade.

Sign in / Sign up

Export Citation Format

Share Document