scholarly journals Immobilization of Dextranase on Nano-Hydroxyapatite as a Recyclable Catalyst

Materials ◽  
2020 ◽  
Vol 14 (1) ◽  
pp. 130
Author(s):  
Yanshuai Ding ◽  
Hao Zhang ◽  
Xuelian Wang ◽  
Hangtian Zu ◽  
Cang Wang ◽  
...  
Keyword(s):  
Sodium Citrate ◽  
Immobilized Enzyme ◽  
Hydroxyapatite Nanoparticles ◽  
X Ray Diffraction ◽  
Enzyme Recycling ◽  
Fourier Transformed Infrared Spectroscopy ◽  
Immobilization Technology ◽  
Ft Ir ◽  
Plaque Biofilm ◽  
Storage Properties

The immobilization technology provides a potential pathway for enzyme recycling. Here, we evaluated the potential of using dextranase immobilized onto hydroxyapatite nanoparticles as a promising inorganic material. The optimal immobilization temperature, reaction time, and pH were determined to be 25 °C, 120 min, and pH 5, respectively. Dextranase could be loaded at 359.7 U/g. The immobilized dextranase was characterized by field emission gun-scanning electron microscope (FEG-SEM), X-ray diffraction (XRD), and Fourier-transformed infrared spectroscopy (FT-IR). The hydrolysis capacity of the immobilized enzyme was maintained at 71% at the 30th time of use. According to the constant temperature acceleration experiment, it was estimated that the immobilized dextranase could be stored for 99 days at 20 °C, indicating that the immobilized enzyme had good storage properties. Sodium chloride and sodium acetic did not desorb the immobilized dextranase. In contrast, dextranase was desorbed by sodium fluoride and sodium citrate. The hydrolysates were 79% oligosaccharides. The immobilized dextranase could significantly and thoroughly remove the dental plaque biofilm. Thus, immobilized dextranase has broad potential application in diverse fields in the future.

scholarly journals STARCH MEDIATED SYNTHESIS OF HYDROXYAPATITE NANOPARTICLE FOR BIOMEDICAL APPLICATIONS

2015 ◽  
Vol 2 (1) ◽  
pp. 15-17
Author(s):  
Indira J
Keyword(s):  
Biomedical Applications ◽  
Soluble Starch ◽  
Morphological Properties ◽  
Spherical Nanoparticles ◽  
Hydroxyapatite Nanoparticles ◽  
X Ray Diffraction ◽  
X Ray ◽  
Ft Ir ◽  
Average Size ◽  
Controllable Size

Hydroxyapatite (HAP) nanoparticles with uniform morphologies and controllable size have been synthesized by template directed method. The environment and eco-friendly polysaccharide soluble starch is used as a template to regulate size and shape of the nanoparticles synthesized. Structural and morphological properties of as-synthesized hydroxyapatite nanoparticles have been examined through the techniques like Fourier Transform Infrared Spectroscopy (FT-IR), X-ray Diffraction (XRD) and Scanning Electron Microscopy(SEM), respectively. The results indicate that the obtained particles are uniform discrete spherical nanoparticles. The average size of the hydroxyapatite nanoparticles were ranged from 45 to 60 nm.

scholarly journals Fabrication of TiO2@Yeast-Carbon Hybrid Composites with the Raspberry-Like Structure and Their Synergistic Adsorption-Photocatalysis Performance

2013 ◽  
Vol 2013 ◽  
pp. 1-8 ◽  
Author(s):  
Dang Yu ◽  
Bai Bo ◽  
He Yunhua
Keyword(s):  
Methylene Blue ◽  
Hybrid Composites ◽  
Light Response ◽  
X Ray Diffraction ◽  
Uniform Size ◽  
Fourier Transformed Infrared Spectroscopy ◽  
Wide Range ◽  
Excellent Photocatalytic Activity ◽  
Ft Ir ◽  
Enhanced Adsorption

In the present work, we report the preparation and photocatalytic properties of TiO2@yeast-carbon with raspberry-like structure using a pyrolysis method. The products are characterized by field emission scanning electron microscopy (FE-SEM), energy dispersive spectrometry (EDS), X-ray diffraction (XRD), thermal gravimetric and differential thermal analysis (TGA-DTA), Fourier transformed infrared spectroscopy (FT-IR), and ultraviolet visible spectroscopy (UV-VIS), respectively. The results show that the hybrid TiO2@yeast-carbon microspheres have ordered elliptic shapes of uniform size (length = 3.5±0.3 μm; width = 2.5±0.5 μm). UV-VIS ascertains that the as-prepared microspheres possess an obvious light response in a wide range of 250–400 nm. In the decomposition of typical model pollutants including methylene blue and congo red, the hybrid composites exhibited excellent photocatalytic activity for the methylene blue due to the enhanced adsorption ability. Further investigation reveals that the combined effect of adsorption from the yeast-carbon core and photocatalytic degradation from the attached TiO2nanoparticles were responsible for the improvement of the photocatalytic activities. Hereby, the raspberry-like TiO2@yeast-carbon has promising applications in water purification.

scholarly journals Structural Characterization of Emeraldine-Salt Polyaniline/Gold Nanoparticles Complexes

2011 ◽  
Vol 2011 ◽  
pp. 1-7 ◽  
Author(s):  
E. A. Sanches ◽  
J. C. Soares ◽  
R. M. Iost ◽  
V. S. Marangoni ◽  
G. Trovati ◽  
...  
Keyword(s):  
Gold Nanoparticles ◽  
Electrostatic Interactions ◽  
Sodium Citrate ◽  
X Ray Diffraction ◽  
Emeraldine Salt ◽  
Salt Form ◽  
Au Nps ◽  
Fourier Transformed Infrared Spectroscopy ◽  
Polyamidoamine Dendrimers

Gold nanoparticles (Au NPs) stabilized with polyamidoamine dendrimers (Au-PAMAM) or sodium citrate (Au-CITRATE) were synthesized and complexed with polyaniline emeraldine-salt form (ES-PANI). The complexes were characterized using structural and morphological techniques, including X-Ray Diffraction (XRD), Scanning Electron Microscopy (SEM), Zeta Potential analyses, and Fourier-Transformed Infrared spectroscopy (FTIR). When the Au-CITRATE NPs are added to the polymeric solution, the formation of a precipitate is clearly observed. The precipitate exhibited a different morphology from that found for ES-PANI and Au-CITRATE NPs, suggesting the formation of ES-PANI coating over the surface of Au-CITRATE NPs. On the other hand, when the Au-PAMAM NPs are incorporated into the ES-PANI solution, none interaction was observed, probably due to the repulsive electrostatic interactions, being the organization of the ES-PANI chains unaffected by the presence of the Au-PAMAM NPs.

scholarly journals Fabrication, Characterization, and Antimicrobial Activity, Evaluation of Low Silver Concentrations in Silver-Doped Hydroxyapatite Nanoparticles

2013 ◽  
Vol 2013 ◽  
pp. 1-9 ◽  
Author(s):  
A. Costescu ◽  
C. S. Ciobanu ◽  
S. L. Iconaru ◽  
R. V. Ghita ◽  
C. M. Chifiriuc ◽  
...  
Keyword(s):  
Antimicrobial Activity ◽  
Raman Spectroscopy ◽  
Hydroxyl Groups ◽  
Major Public Health Problem ◽  
Hydroxyapatite Nanoparticles ◽  
X Ray Diffraction ◽  
X Ray ◽  
Ft Raman Spectroscopy ◽  
Ft Ir ◽  
Ft Raman

The aim of this study was the evaluation of(Ca10-xAgx)(PO4)6(OH)2nanoparticles (Ag:HAp-NPs) for their antibacterial and antifungal activity. Resistance to antimicrobial agents by pathogenic bacteria has emerged in the recent years as a major public health problem worldwide. In this paper, we report a comparison of the antimicrobial activity of low concentrations silver-doped hydroxyapatite nanoparticles. The silver-doped nanocrystalline hydroxyapatite powder was synthesized at 100°C in deionised water. The as-prepared Ag:Hap nanoparticles were characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM), FT-IR, and FT-Raman spectroscopy. X-ray diffraction (XRD) studies demonstrate that powders obtained by coprecipitation at 100°C exhibit the apatite characteristics with good crystal structure, without any new phase or impurities found. FT-IR and FT-Raman spectroscopy revealed the presence of the various vibrational modes corresponding to phosphates and hydroxyl groups and the absence of any band characteristic to silver. The specific microbiological assays demonstrated that Ag:HAp-NPs exhibited antimicrobial features, but interacted differently with the Gram-positive, Gram-negative bacterial and fungal tested strains.

scholarly journals L-Leucine Templated Biomimetic Assembly of SnO2 Nanoparticles and Their Lithium Storage Properties

Scanning ◽  
2018 ◽  
Vol 2018 ◽  
pp. 1-8 ◽  
Author(s):  
Peng Yu ◽  
Mili Liu ◽  
Haixiong Gong ◽  
Fangfang Wu ◽  
Zili Yi ◽  
...  
Keyword(s):  
Growth Regulation ◽  
Sno2 Nanoparticles ◽  
Sol Gel ◽  
Lithium Ion ◽  
X Ray Diffraction ◽  
Lithium Storage ◽  
X Ray ◽  
Ft Ir ◽  
Storage Properties ◽  
High Calcination Temperature

SnO2 nanoparticles have been synthesized by a novel route of a sol-gel method assisted with biomimetic assembly using L-leucine as a biotemplate. The microstructure of as-prepared SnO2 nanoparticles was characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), Fourier transform infrared spectra (FT-IR), and Brunner−Emmet−Teller (BET) measurements. The results demonstrated that the growth of SnO2 could be regulated by L-leucine at a high calcination temperature. The electrochemical performance of SnO2 was also measured as anodes for lithium-ion battery. It is a guidance for the growth regulation of SnO2 at high temperature to obtain SnO2/C with nanosized SnO2 coated by a graphitic carbon.

scholarly journals Hydroxyapatite-Functionalized Graphene: A New Hybrid Nanomaterial

2014 ◽  
Vol 2014 ◽  
pp. 1-7 ◽  
Author(s):  
C. Rodríguez-González ◽  
H. E. Cid-Luna ◽  
P. Salas ◽  
V. M. Castaño
Keyword(s):  
Electron Microscopy ◽  
Physicochemical Process ◽  
Functionalized Graphene ◽  
Hydroxyapatite Nanoparticles ◽  
X Ray Diffraction ◽  
X Ray ◽  
Hybrid Nanomaterial ◽  
Transmission Electron ◽  
Ft Ir ◽  
Graphene Oxide Sheets

Graphene oxide sheets (GO) were functionalized with hydroxyapatite nanoparticles (nHAp) through a simple and effective hydrothermal treatment and a novel physicochemical process. Microstructure and crystallinity were investigated by Fourier transform infrared spectroscopy (FT-IR), Raman spectroscopy, X-ray diffraction (XRD), ultraviolet-visible (UV-Vis) absorption spectroscopy, and thermogravimetric analysis (TGA). Transmission electron microscopy (TEM) and scanning electron microscopy (SEM) were performed to characterize the morphology of the functionalized material. The resulting novel materials combine the biocompatibility of the nHAp with the strength and physical properties of the graphene.

Preparation and Structural Characterization of SiO2-ZrO2 Aerogels

2007 ◽  
Vol 336-338 ◽  
pp. 2282-2285
Author(s):  
Xiao Dong He ◽  
He Xin Zhang ◽  
Yao Li ◽  
Chang Qing Hong ◽  
Jiu Peng Zhao
Keyword(s):  
Average Pore Size ◽  
Supercritical Drying ◽  
X Ray Diffraction ◽  
Average Pore ◽  
Surface Areas ◽  
Fourier Transformed Infrared Spectroscopy ◽  
Transmission Electron ◽  
Ft Ir ◽  
Chemical Conditions

Low density SiO2-xZrO2 aerogels with x=35wt%, 65wt%, 75wt%, 90wt%, 95wt% were prepared by CO2 supercritical drying technique with tetraethylorthosilicate (TEOS) and zirconyl nitrate dihydrate (ZrO(NO3)2 .2H2O) by hydrolytic polycondensation under different chemical conditions. The prepared aerogels are performed by X-ray Diffraction (XRD), Transmission electron microscopy (TEM), Fourier transformed infrared spectroscopy (FT-IR) and BET surface areas to characterize and analyze the morphology and pore structure of SiO2-ZrO2 aerogels. The results showed that the SiO2-ZrO2 areogels are the typical of nano mesopores and the average pore size is about 50 nm. The specific surface areas varied from 345.5 to 615.5 m2/g with (SBET)MAX = 615.5 m2/g with 20wt% Zirconia; Moreover a mass of Si-O-Zr bands formed in the aerogels and the formation mechanism of Si-O-Zr bands are also discussed.

Synthesis of MIL-125/Graphene Oxide Composites and Hydrogen Storage Properties

2017 ◽  
Vol 727 ◽  
pp. 683-687 ◽  
Author(s):  
Tian Bao Yang ◽  
Li Xian Sun ◽  
Fen Xu ◽  
Zi Qiang Wang ◽  
Yong Jin Zou ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Graphene Oxide ◽  
Hydrogen Storage ◽  
Parent Material ◽  
X Ray Diffraction ◽  
Hydrogen Storage Properties ◽  
Transmission Electron ◽  
Metal Organic ◽  
Ft Ir ◽  
Storage Properties

Metal-organic frameworks (MOFs: MIL-125)-graphene oxide (GO) composite (MO) was synthesized by solvothermal method. All the materials were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), thermogravimetric analysis (TGA), high resolution transmission electron microscopy (HRTEM), Fourier transform infrared spectroscopy (FT-IR) and Raman spectroscopy. Then their hydrogen storage properties were systematically tested under 1 bar and 77K. The composite material MO-1 possesses higher surface area than the parent material MIL-125 and shows a remarkable H2 capacity up to 2.5 wt% (38% increases vs. MIL-125).

scholarly journals Extraction of Hydroxyapatite from Caprine Bones and its Anti-Bacterial Study

2021 ◽  
Vol 40 (4) ◽  
pp. 867-873
Author(s):  
Mujeeb Ur Rehman Rehman ◽  
Ayatullah Qureshi ◽  
Muhammad Moazam Baloch
Keyword(s):  
Antibacterial Activity ◽  
Milling Process ◽  
X Ray Diffraction ◽  
Zone Of Inhibition ◽  
X Ray ◽  
Bacterial Response ◽  
Fourier Transformed Infrared Spectroscopy ◽  
Inorganic Substances ◽  
Animal Bones ◽  
Ft Ir

Bones are mineralized connecting tissues consisting of 70% of Hydroxyapatite (HAP); it is the major component of the bone. Hydroxyapatite (HAP) is most important biomaterial possessing all distinguish features such as antibacterial activity, bioactive and non-inflammatory behavior. Hydroxyapatite is mainly synthesized by two routes i.e. i) using inorganic substances and ii) by exploiting natural sources. The aim of this study is to extract hydroxyapatite using solid waste (animal bones) and to investigate its antibacterial activity. The extraction consisted of alkaline technique and calcination methods. During alkaline process bones became very soft and were easily converted into powder using mortar and pestle without utilizing any milling process and anti-bacterial response was higher when compared to previous studies. The characterization techniques that were utilized are; X-Ray Diffraction (XRD), Fourier Transformed Infrared Spectroscopy (FT-IR) and SEM (Scanning Electron Microscopy (SEM) in order to reveal phase composition, functional groups and surface morphology of HAP. Antibacterial activity was checked by zone of inhibition

scholarly journals Valorization of glass and shell powders in the synthesis of Belitic clinker

2018 ◽  
Vol 149 ◽  
pp. 01021 ◽  
Author(s):  
A. Bouregba ◽  
A. Diouri ◽  
F. Amor ◽  
H. Ez-zaki ◽  
O. Sassi
Keyword(s):  
Materials Science ◽  
Raw Materials ◽  
Construction Materials ◽  
Waste Recycling ◽  
Hydration Products ◽  
X Ray Diffraction ◽  
X Ray ◽  
Fourier Transformed Infrared Spectroscopy ◽  
Ft Ir ◽  
Mussel Shells

In recent years, waste recycling has become a key issue in construction materials science for achieve the goal of sources of raw materials. The aim of this study is to use waste glass as source of SiO2 oxide and mussel shells consisting essentially of calcium carbonate as starting materials to synthesize belite rich cement. The elaborated clinker is chemically and structurally related to β-Ca2SiO4, by heat solid state activation. After grinding, the raw materials are mixed and heated up to 1050°C. The samples are characterized by X-ray diffraction (XRD) and Fourier Transformed Infrared spectroscopy (FT-IR). The mechanical strength of some sample was measured for 28 and 72 days. The results show the different mineralogical stapes of formation of clinker, the state reaction method allows the elaboration of a cementitious material by a simple heat treatment at relatively low temperature and low release of CO2. The hydration products are also identified by XR diffraction at 2, 7, 28 and 72 days.

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