scholarly journals Hydroxyapatite-Based Magnetic Bionanocomposite as Pharmaceuticals Carriers in Chitosan Scaffolds

2021 ◽  
Vol 5 (2) ◽  
pp. 37
Author(s):  
Anderson Valério Chaves ◽  
Rafael Melo Freire ◽  
Victor Pinheiro Feitosa ◽  
Nágila Maria Pontes Silva Ricardo ◽  
Juliano Casagrande Denardin ◽  
...  
Keyword(s):  
Bone Growth ◽  
Average Particle Size ◽  
Electronic Spectroscopy ◽  
Average Particle ◽  
High Porosity ◽  
Magnetite Fe3o4 ◽  
Freeze Dried ◽  
Chitosan Scaffolds ◽  
Co Precipitation ◽  
New System

Hydroxyapatite (HA) is a bioceramic very similar to the mineral component of bones and teeth. It is well established that osteoblasts grow better onto HA-coated metals than on metals alone. Herein, the preparation of a new system consisting of magnetite (Fe3O4) and HA functionalized with oleic acid and simvastatin (SIMV), and incorporated in chitosan (CHI) scaffolds, was undertaken. HA was synthesized by the hydrothermal method, while Fe3O4 was synthesized by co-precipitation. The polymer matrix was obtained using a 2% CHI solution, and allowed to stir for 2 h. The final material was freeze-dried to produce scaffolds. The magnetic properties remained unchanged after the formation of the composite, as well as after the preparation of the scaffolds, maintaining the superparamagnetism. CHI scaffolds were analyzed by scanning electronic spectroscopy (SEM) and showed a high porosity, with very evident cavities, which provides the functionality of bone growth support during the remineralization process in possible regions affected by bone tissue losses. The synthesized composite showed an average particle size between 15 and 23 nm for particles (HA and Fe3O4). The scaffolds showed considerable porosity, which is important for the performance of various functions of the tissue structure. Moreover, the addition of simvastatin in the system can promote bone formation.

scholarly journals Thermal, Structural, and Physical Properties of Freeze Dried Tropical Fruit Powder

2014 ◽  
Vol 2014 ◽  
pp. 1-10 ◽  
Author(s):  
K. A. Athmaselvi ◽  
C. Kumar ◽  
M. Balasubramanian ◽  
Ishita Roy
Keyword(s):  
Particle Size ◽  
Physical Properties ◽  
Average Particle Size ◽  
Average Particle ◽  
X Ray Diffraction ◽  
Tropical Fruit ◽  
X Ray ◽  
Freeze Dried ◽  
Fruit Powder ◽  
Lcr Meter

This study evaluates the physical properties of freeze dried tropical (guava, sapota, and papaya) fruit powders. Thermal stability and weight loss were evaluated using TGA-DSC and IR, which showed pectin as the main solid constituent. LCR meter measured electrical conductivity, dielectric constant, and dielectric loss factor. Functional groups assessed by FTIR showed presence of chlorides, and O–H and N–H bonds in guava, chloride and C–H bond in papaya, and chlorides, and C=O and C–H bonds in sapota. Particle size and type of starch were evaluated by X-ray diffraction and microstructure through scanning electronic microscopy. A semicrystalline profile and average particle size of the fruit powders were evidenced by X-ray diffraction and lamellar/spherical morphologies by SEM. Presence of A-type starch was observed in all three fruits. Dependence of electric and dielectric properties on frequency and temperature was observed.

scholarly journals Photocatalytic degradation of chlortetracycline hydrochloride in marine aquaculture wastewater under visible light irradiation with CuO/ZnO

2019 ◽  
Vol 80 (7) ◽  
pp. 1249-1256 ◽  
Author(s):  
Jinghua Liu ◽  
Xiaocai Yu ◽  
Liping Wang ◽  
Meicen Guo ◽  
Wanting Zhu ◽  
...  
Keyword(s):  
Visible Light ◽  
Photocatalytic Degradation ◽  
Diffuse Reflectance Spectroscopy ◽  
Average Particle Size ◽  
Molar Ratio ◽  
Average Particle ◽  
Marine Aquaculture ◽  
Aquaculture Wastewater ◽  
Co Precipitation ◽  
The Cost

Abstract A CuO/ZnO photocatalyst nanocomposite was successfully prepared by co-precipitation and characterized by investigating its chemical and physical properties by X-ray diffraction, scanning electron microscopy, energy dispersive spectroscopy, UV-vis diffuse reflectance spectroscopy and photoluminescence spectroscopy. The average particle size of CuO/ZnO composite was found to be around 80 nm. The degradation of chlortetracycline hydrochloride pollutants in marine aquaculture wastewater using ZnO and CuO/ZnO was compared and it was found that CuO/ZnO nanocomposite is more efficient than ZnO. The effects of external factors on the photocatalytic effectiveness of nanocomposite were investigated under visible light. Also, the photocatalytic conditions for the degradation of chlortetracycline hydrochloride by the nanocomposite were optimized. Based on both ability and efficiency of degradation, and on the cost and availability, 10:2 molar ratio of Zn2+/Cu2+ and 0.7 g/L nanocomposite, was found to be optimal, in which case the average photocatalytic degradation rate of chlortetracycline hydrochloride reached 91.10%.

Morphology-Controlled CaCO3 Nanostructures by Modified Co-Precipitation in Pulsed Mode

2015 ◽  
Vol 752-753 ◽  
pp. 148-153
Author(s):  
M.M. Nassar ◽  
Taha Ebrahiem Farrag ◽  
M.S. Mahmoud ◽  
Sayed Abdelmonem
Keyword(s):  
Particle Size ◽  
Calcium Carbonate ◽  
Rotation Speed ◽  
Average Particle Size ◽  
Calcium Nitrate ◽  
Precipitation Method ◽  
Average Particle ◽  
X Ray ◽  
Co Precipitation ◽  
Pulsed Mixing

Calcium carbonate nanoparticles and nanorods were synthesized by precipitation from saturated sodium carbonate and calcium nitrate aqueous solutions through co precipitation method. A new rout of synthesis was done by both using pulsed mixing method and controlling the addition of calcium nitrate. The effect of the agitation speed, and the temperature on particle size and morphology were investigated. Particles were characterized using X-ray Microanalysis, X-ray analysis (XRD) and scanning electron microscopy (SEM). The results indicated that increasing the mixer rotation speed from 3425 to 15900 (rpm) decreases the average particle size to 64±7 nm. A rapid nucleation then aggregation induced by excessive shear force phenomena could explain this observation. Moreover, by increasing the reaction temperature, the products were converted from nanoparticle to nanorods. The maximum attainable aspect ratio was 6.23 at temperature of 75°C and rotation speed of 3425. Generally, temperature raise promoted a significant homoepitaxial growth in one direction toward the formation of calcite nanorods. Overall, this study can open new avenues to control the morphology of the calcium carbonate nanostructures.

Effect of Surfactant on the Preparation of Nano-powder for Yb Doping Laser Transparent YAG Ceramic

2013 ◽  
Vol 32 (5) ◽  
pp. 511-515 ◽  
Author(s):  
Xiao Guo Cao ◽  
Jia Wang ◽  
Qi Bai Wu ◽  
Hai Yan Zhang
Keyword(s):  
Particle Size ◽  
Polyethylene Glycol ◽  
Average Particle Size ◽  
Ammonium Bicarbonate ◽  
Spherical Particles ◽  
Precipitation Method ◽  
Average Particle ◽  
X Ray Diffraction ◽  
Nano Powder ◽  
Co Precipitation

AbstractYb:YAG transparent ceramic nano-powder was prepared by chemical co-precipitation method, with ammonium bicarbonate as the precipitant and polyethylene glycol as surfactant. The addition of polyethylene glycol can reduce the agglomeration and particle size of the prepared Yb:YAG powder. The morphology, thermal stability and phase structure of Yb:YAG nano-powder were charactered by scanning electron microscopy (SEM), thermogravimetry and differential thermal analysis (TG-DTA), X-ray diffraction (XRD), and Fourier transform infrared spectroscopy. The results show that well-crystallized nano-powder was obtained by calcining the precursors at 900 °C for 3 h. The average particle size of Yb:YAG powder is about 100–200 nm. When the volume amount of polyethylene glycol is 2.0%, well-dispersed Yb:YAG powder with spherical particles of 100 nm diameter was obtained.

scholarly journals Fabrication and Magnetic Properties of Mn1 - xZnxFe2O4 (0 ≤ x ≤ 0.8) Nanoparticles

2009 ◽  
Vol 19 (1) ◽  
pp. 19-25
Author(s):  
Pham Hoai Linh ◽  
Tran Dang Thanh ◽  
Do Hung Manh ◽  
Nguyen Chi Thuan ◽  
Le Van Hong ◽  
...  
Keyword(s):  
Magnetic Properties ◽  
Biomedical Applications ◽  
Spinel Ferrite ◽  
Average Particle Size ◽  
Precipitation Method ◽  
Average Particle ◽  
Promising Candidate ◽  
Zn Concentration ◽  
Co Precipitation ◽  
Curie Temperature Tc

In this paper, we report results on the fabrication and magnetic properties of spinel ferrite Mn1-xZnxFe2O4 (0 ≤ x ≤ 0.8) nanoparticles. The nanoparticles were synthesized by a co-precipitation method. The effects of substituting Zn for Mn on the magnetic properties and particles size were focused. It was found that the phase-formation temperature is 90OC and the average particle size decreases from 40 nm to 10 nm when increased Zn concentration from zero to 0.8. The Curie temperature TC strongly decreases from 585 K (x = 0) to 320 K (x = 0.8) concomitantly with a decrease of the saturation magnetization MS. With a TC of 320 K and MS of 17 emu/g, the x=0.8 sample could be a promising candidate for some biomedical applications.

scholarly journals SYNTHESIS OF COMPLEX OXIDE COMPOSITIONS OF COBALT–MANGANESE AND CERIUM–ZIRCONIUM AND THEIR CATALYTIC ACTIVITY IN THE DECOMPOSITION OF HYDROGEN PEROXIDE

2019 ◽  
Vol 85 (11) ◽  
pp. 15-27
Author(s):  
Yuliia Pohorenko ◽  
Anatoliy Omel’chuk ◽  
Olexandr Ivanenko ◽  
Tamara Pavlenko
Keyword(s):  
Heat Treatment ◽  
Hydrogen Peroxide ◽  
Catalytic Activity ◽  
Mixed Oxides ◽  
Average Particle Size ◽  
Complex Oxide ◽  
Ammonia Solution ◽  
Average Particle ◽  
Zirconium Oxides ◽  
Co Precipitation

Cobalt oxides and/or manganese and their com-position based on cerium and zirconium oxides (CeO2 : ZrO2 = 1:1 mol.%) with a content of up to 20 wt. % are synthesized. Samples of both individual oxides and complex oxide compositions were prepared by precipitation from solutions of am-monia (room temperature) or hexamethylenetet-ramine (80–90 °C) followed by heat treatment. Results of DTA show, that due to the calcination at 400 ° C (2 h), the obtained samples lose 17–22 wt. % corresponding to 2–3.8 molecules of water. According to the X-ray powder analysis, initially are formed hydroxide compounds of cobalt (CoO· xH2O) and manganese (MnO2·yН2О), which, after being heated at 400 °C for 2 hours, are converted into mixed oxides from the composition of Co3O4 and Mn3O4. The average particle size calculated by the Sherer equation is 18–30 nm. In the study of catalytic activity on the example of the reaction of the hydrogen peroxide decomposition, it was found that the obtained samples from the solution of GMTA show a greater ability to catalytically decompose hydrogen peroxide compared to samples obtained from the ammonia solution. In this case, the catalytic activity of dried samples is twice as high as roasted, regardless of the method of obtaining. Samples of oxide compo-sitions with deposited 5–10 wt. % of Ce–Zr oxides (1:1) exhibit the highest ability to decompose H2O2. In this case, samples of compositions obtained from the solution of GMTA, have a prolonged catalytic action, and when precipitation in the solution of ammonia, the reaction takes place quite actively during 4–5 days. Compositions formed from co-deposited or mechanically mixed hydroxocompounds of cobalt and manganese with 5 wt. % of CeO2–ZrO2 (1:1) deposited on them have different catalytic activity. In the case of mechanically mixed, it is 30% lower and with subsequent calcination at 400 °C, it is reduced by almost half, and with co-precipitation, the activity is quite high and does not change with heat treatment. In the case of obtaining samples of Co–Mn with Ce–Zr (1:1) deposited on them in excess of 10 wt. % the catalytic activity of the samples dried at 80 °C is equal to the activity of the co-deposited hydroxocompounds of cobalt and manganese and  the  calcination  at  400  °C  it  reduces  it by  30 %. The best ability for catalysis was found in samples CoO·xH2O + 5 wt. % MnO2·yН2О, СоO×хН2О + 10 wt. % CeO2:ZrO2 and СоO×хН2О–MnO2×yН2О, precipitated with the GMTA solution and dried at 80 °C. The besser catalytic properties revealed a sample of СоО×хН2О + 10 wt. % CeO2:ZrO2, which with-out stirring is capable of decomposing 1.2–1.4 dm3/g of hydrogen peroxide with a rapid reaction and in the experiment the volume of H2O2 reacted was 3.4 dm3/g.

scholarly journals Synthesis and Characterization of Co2+ Ions Doped ZnS-CdS Composite Nanopowder

2020 ◽  
Author(s):  
Madhavi Jonnalagadda
Keyword(s):  
Average Particle Size ◽  
Exchange Interactions ◽  
Host Lattice ◽  
Material Surface ◽  
Precipitation Process ◽  
Average Particle ◽  
Magnetic Studies ◽  
Chemical Homogeneity ◽  
Ferromagnetic Nature ◽  
Co Precipitation

ZnS-CdS composite nano-powder doped with (0.01 mol %) Cobalt has been collected by a co-precipitation process at 300 K. The sample is characterized by structural, combined spectroscopic methods and magnetic studies. The prepared samples were belonging to cubic structure no impurity phases were observed. Doping of cobalt increase the neighborhood strain assessment and a decreases lattice constants decides from x-ray diffraction data. The crystallite size is 10.42nm. From UV-absorption and EPR studies revealed that the energy band gap of Co2+ doped ZnS-CdS composite nanopowder and extension of sp-d exchange interactions and common d-d transitions. The variation in the energy bandgap varies as a function of cobalt concentration is due to structural modification. Photoluminescence spectrum reveals the defect-related emissions and shows the formation of luminescence. FT-IR spectrum confirmed the feature vibrational manner of Zn, Cd, O–H and sulfide ions are in the host lattice. The doping-induced magnetic properties are studied by vibrating sample magnetometer which matches with the theoretical values besides ferromagnetic nature. Magnetic studies confirm the ferromagnetic nature of the material. Surface morphology and chemical homogeneity studies were carried out by using SEM with EDAX. Transmission electron microscope recommends the crystalline nature of nanoparticles, with average particle size is of the order of 20-100nm.

scholarly journals Study Microstructure of Fe3O4 Modification Using PEG 4000 form Iron Sand at Wari Ino Beach As A Biosensor Application

2021 ◽  
Vol 8 (3) ◽  
pp. 168-171
Author(s):  
Kurnia Kurnia ◽  
Meidy Kaseside ◽  
Steven Iwamony
Keyword(s):  
Average Particle Size ◽  
Precipitation Method ◽  
High Dispersion ◽  
Average Particle ◽  
X Ray Diffraction ◽  
Xrd Pattern ◽  
Peg 4000 ◽  
Biosensor Application ◽  
Scherrer Formula ◽  
Co Precipitation

Fe3O4 encapsulated PEG form iron sand at wari ino beach has been successfully synthesized by co-precipitation method. The average particle size  of the nanoparticle 11,3 nm was determined by scherrer formula. Fe3O4 modification PEG 4000 was successfully encapsulated the samples  by the presence C-O-C and CH bonding that were characterized using Fourier Transform Infra Red (FTIR), X-Ray Diffraction (XRD) pattern  shows that all samples  are formed by single  phase cubic spinel magnetite  , and Scanning Electron Microscopy (SEM) shows the  high dispersion capability while encapsulated process using  PEG. The results of the characterization show that the Fe3O4 successfully encapsulated by PEG 4000.

Exploring the interaction of l-cysteine capped CuS nanoparticles with bovine serum albumin (BSA): a spectroscopic study

RSC Advances ◽  
2016 ◽  
Vol 6 (63) ◽  
pp. 58288-58295 ◽  
Author(s):  
S. Prasanth ◽  
D. Rithesh Raj ◽  
T. V. Vineeshkumar ◽  
Riju K. Thomas ◽  
C. Sudarsanakumar
Keyword(s):  
Particle Size ◽  
Bovine Serum Albumin ◽  
Serum Albumin ◽  
Bovine Serum ◽  
Copper Sulfide ◽  
Average Particle Size ◽  
Precipitation Method ◽  
Average Particle ◽  
Spectroscopic Techniques ◽  
Co Precipitation

l-Cysteine capped copper sulfide nanoparticles with an average particle size of 6 nm were synthesized using a chemical co-precipitation method and their interactions with bovine serum albumin were explored using various spectroscopic techniques.

Preparation of Nanostructured Metal Ferrite Particles by Sonochemistry

2005 ◽  
Vol 277-279 ◽  
pp. 1044-1048 ◽  
Author(s):  
Eun Hee Kim ◽  
Hyo Sook Lee ◽  
Hui Ping Shao
Keyword(s):  
Magnetic Field ◽  
Particle Size ◽  
Cobalt Ferrite ◽  
Average Particle Size ◽  
Iron Chloride ◽  
Precipitation Method ◽  
Average Particle ◽  
Sonochemical Method ◽  
Iron Ferrite ◽  
Co Precipitation

Nanostructured iron and cobalt ferrite particles were prepared from iron chloride and cobalt chloride, respectively, using the sonochemical method. The particles were compared with those synthesized using the co-precipitation method. The properties of the particles were characterized using various techniques, such as XRD, TEM, VSM and a SQUID magnetometer. The iron ferrite particles had an average particle size of about 15 nm and a magnetization value of 83 emu/g at a magnetic field of 50 kOe, while the particle size of cobalt ferrite was about 5 nm and its magnetization value was 33 emu/g at the same magnetic field.

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