Biomimetic Magnetic Nanoparticles for Hyperthermia Treatment

2011 ◽  
Vol 493-494 ◽  
pp. 16-19
Author(s):  
E.M. Múzquiz-Ramos ◽  
Dora A. Cortés-Hernández ◽  
C.G. Sánchez-Torres ◽  
José C. Escobedo-Bocardo ◽  
A. Zugasti ◽  
...  
Keyword(s):  
Magnetic Particles ◽  
Sol Gel ◽  
Apatite Layer ◽  
Apatite Formation ◽  
Temperature Profiles ◽  
Osteosarcoma Cell ◽  
Hyperthermia Treatment ◽  
Before And After ◽  
Magnetite Particles ◽  
Co Precipitation

The aim of this work was the synthesis of bioactive magnetic particles (BMP) which are expected to form a thin apatite layer on its surface that may bond to bone with the osseous carcinogen tissue. Magnetite and Mg0.6Ca0.4Fe2O4 nanoparticles were obtained by a reverse co-precipitation and sol-gel methods, respectively. Magnetite particles were coated with chitosan in order to obtain a stable ferrofluid. Then both ferrites were biomimetically treated using two different simulated body fluids (SBF and 1.5 SBF). An apatite layer was formed on both types of BMP after the biomimetic treatment. Both ferrites showed superparamagnetic behavior before and after the apatite formation. Their time-dependent temperature profiles were measured under the effect of an AC magnetic field (AMF). After less than 20 min of applying the AMF an appropriate temperature for hyperthermia treatment was obtained. No citotoxicity was observed after osteosarcoma cell culture testing of BMP. Furthermore, after applying an AMF to the cells in contact with the BMP, the cells viability decreased considerably.

Treatment of Dye Wastewater by Adsorption with Bentonite-Supported Magnetic Materials

2011 ◽  
Vol 340 ◽  
pp. 487-491
Author(s):  
Xiao Ming Chen ◽  
Jian Feng Ma ◽  
Ding Long Li
Keyword(s):  
Removal Efficiency ◽  
Contact Time ◽  
Magnetic Particles ◽  
Influence Factor ◽  
Dye Wastewater ◽  
No Adsorption ◽  
Initial Concentration ◽  
Magnetite Particles ◽  
Co Precipitation ◽  
Maximum Removal

Bentonite-supported magnetite particles (MagBt-p) were prepared by co-precipitation. The adsorption capacity of Bentonite-supported magnetic particles on waste water containing OrangeⅡ was tested. Some influence factor such as the dose, the initial concentration of OrangeⅡ, the pH, the contact time and the presence of surfactant were studied. Results showed that cation surfactant (CTAB) greatly enhanced the adsorption of OrangeⅡ. The maximum removal efficiency was 96.6% at 180mg/L (CTAB) and beyond this concentration there was almost no adsorption. Besides, the removal efficiency was affected by pH and contact time, the maximum removal efficiency was found at pH 2.1-3, the adsorption was rapid during the first 120 min and then equilibrium within 180min.

Mechanism of Apatite Formation on Bioactive Titanium Metal

1999 ◽  
Vol 599 ◽  
Author(s):  
T. Kokubo ◽  
H.-M. Kim ◽  
H. Takadama ◽  
M. Uchida ◽  
S. Nishiguchi ◽  
...  
Keyword(s):  
Sol Gel ◽  
Sodium Titanate ◽  
Amorphous Structure ◽  
Apatite Layer ◽  
Apatite Formation ◽  
Titanium Metal ◽  
Oh Groups ◽  
Living Body ◽  
Heat Treated ◽  
Bonelike Apatite

AbstractThe present authors previously showed that titanium metal, which was exposed to 5.OMNaOH solution at 60°C for 24 h and heat-treated at 600°C for 1 h, spontaneously forms a bonelike apatite layer on its surface in the living body, and tightly bonds to the bone through the apatite layer. In the present study, mechanism of the apatite formation on the bioactive titanium metal was investigated in an acellular simulated body fluid (SBF). A thin sodium titanate layer was formed on the surface of the titanium metal by the NaOH and heat treatments. The sodium titanate layer released Na+ ions via exchange with H3O+ ions in SBF, to form a lot of Ti-OH groups on its surface. The Ti-OH groups first combined with Ca2+ ions in SBF, and then later with PO43- ions to form the apatite. Titania and Na2O-TiO2 gels prepared by a sol-gel method as model substances of the sodium titanate layer on the surface of the titanium metal showed that Ti-OH groups of anatase structure are effective for the apatite nucleation, whereas those of amorphous structure and Na2Ti5O11 crystal are not effective.

The Structural and Compositional Evaluation of Some Calcium Phosphate Glasses with Bioactive Potential

2018 ◽  
Vol 69 (6) ◽  
pp. 1424-1428
Author(s):  
Daniela Avram ◽  
Dan Ungureanu ◽  
Nicolae Angelescu ◽  
Ionica Ionita ◽  
Anca Gheboianu ◽  
...  
Keyword(s):  
Sol Gel ◽  
Diffraction Method ◽  
Phosphate Glasses ◽  
Apatite Formation ◽  
Silica Network ◽  
Scanning Calorimetry ◽  
Two Samples ◽  
Before And After ◽  
Bioactive Potential ◽  
Doped Glass

This paper shows the experimental results of two compositional phosphocalcic glasses: 50% SiO2 - 45% CaO - 5% P2O5 and 47% SiO2 - 45% CaO - 5% P2O5 - 3% Ag2O obtained through sol-gel method. In order to study their bioactivity, the two compositions were structural analyzed by X-ray diffraction method. In this case the apatite formation was highlighted after 14 days of soaked in simulated body fluid, but also other compounds (CaCO3, AgCl and Ag) resulting from the same process were highlighted. The first glass composition is more bioactive than composition doped with silver. The pores of the hydrated silica network are partially clogged by the AgCl formed, which can reduce the rate of hydroxyapatite formation but this process does not cancel the bioactivity of the doped glass. The functional groups present in the structure of those two glasses before and after soaking (PO43-, CO32- and HO-) were highlighted by the Fourier Transform Infrared Spectroscopy (FTIR). The elemental chemical composition was confirmed by elemental analysis WD-XRF. The particle size and the two samples stability was analyzed by Dynamic Light Scattering (DLS), Thermogravimetric Analysis (TG) and Differential Scanning Calorimetry (DSC). The granulometric analysis shows that the glass particles have average diameters of 647.9 nm for the first composition, respectively 380.4 nm for glass doped with silver. TG analysis show a total loss of weight of 8.3% for the first glass, respectively 3.72% for doped glass, which demonstrates that the two compositions are thermally stable.

scholarly journals Investigating the Intermediate Water Feature of Hydrated Titanium Containing Bioactive Glass

2021 ◽  
Vol 22 (15) ◽  
pp. 8038
Author(s):  
Mostafa Mabrouk ◽  
Hanan H. Beherei ◽  
Yukiko Tanaka ◽  
Masaru Tanaka
Keyword(s):  
Sol Gel ◽  
Morphological Properties ◽  
Intermediate Water ◽  
Osteosarcoma Cell ◽  
Surface Charges ◽  
Bioactive Glasses ◽  
Remarkable Effect ◽  
Dsc Measurements ◽  
Before And After ◽  
Ti Doping

Intermediate water (IW) in hydrated bioactive glasses remains uninvestigated. We obtained titanium (Ti)-containing bioactive glasses (BGTs) (Ti at 5%, 7.5% and 10% of the glass system) using the sol–gel technique. Their thermal, physicochemical, and morphological properties, before and after Ti-doping, were analysed using DTA, XRD, FTIR, TEM, and SEM accessorised with EDAX, and size distribution and zeta potential surface charges were determined using a NanoZetasizer. The IW in hydrated BGTs was investigated by cooling and heating runs of DSC measurements. Moreover, the mode of death in an osteosarcoma cell line (MG63) was evaluated at different times of exposure to BGT discs. Ti doping had no remarkable effect on the thermal, physicochemical, and morphological properties of BGTs. However, the morphology, size, and charges of BGT nano-powders were slightly changed after inclusion of Ti compared with those of BGT0; for example, the particle size increased with increasing Ti content (from 4–5 to 7–28 nm). The IW content was enhanced in the presence of Ti. The mode of cell death revealed the effect of IW content on the proliferation of cells exposed to BGTs. These findings should help improve the biocompatibility of inorganic biomaterials.

scholarly journals SYNTHESIS OF BIO-NANOMAGNETITE AND ITS OPTIMIZED CONDITIONS FOR PHTHALATE ABSORBTION

2020 ◽  
Vol 4 (3) ◽  
pp. 1-12
Author(s):  
Seyedeh Farzaneh Hosseini ◽  
Zarrin Eshaghi
Keyword(s):  
Fourier Transform ◽  
Magnetic Particles ◽  
Polymeric Nanoparticles ◽  
Precipitation Method ◽  
Magnetic Characteristics ◽  
Coated Particles ◽  
Magnetite Particles ◽  
Co Precipitation ◽  
Optimized Conditions ◽  
Vast Range

Motivation/Background: Magnetic polymeric nanoparticles have vast range of applications in various fields. Coating or encapsulating of magnetic particles with polymers is one of the most useful methods of modifying magnetic nanoparticles. As these coated particles have magnetic characteristics, they can be easily collected with a single magnet instead of burdensome and time-consuming methods such as centrifugation. Method: In this work, nano magnetite particles were synthesized using co-precipitation method and then they were firstly coated with a single biodegradable co-polymer, i.e. poly(butylene adipate-co-terephthalate) (PBAT), and secondly with a mixture of two biodegradable polymers of PBAT and poly(butylene adipate) (PBA). Results: Fourier Transform Infrared (FTIR) spectrum of these two bio-nanoparticles showed their characteristics. They were also used to absorb dibutyle phthalate and dioctyle phthalate from aqueous solutions. UV-Vis was used to characterize optimization of particle mass, time and stirring speed during absorption. XRD spectrum was also taken. Volume, time and stirring speed of desorption were also optimized. In addition, calibration was performed, and the isotherm was plotted for two particles. Conclusions: According to XRD spectrum, particles were in nano range. They had acceptable biodegradation characteristics. They also were efficient in absorbing and desorbing phthalates and were collected easily through magnet.

The Impact of Stirring Rate on the Crystallinity and Bioactivity of 58S Bioactive Glass

2011 ◽  
Vol 493-494 ◽  
pp. 43-48 ◽  
Author(s):  
Ourania Menti Goudouri ◽  
Maria Perissi ◽  
Eleni Theodosoglou ◽  
Lambrini Papadopoulou ◽  
Xanthippi Chatzistavrou ◽  
...  
Keyword(s):  
Bioactive Glass ◽  
Sol Gel ◽  
Apatite Formation ◽  
Reinforcing Agent ◽  
Main Crystalline Phase ◽  
Before And After ◽  
Amorphous Glass ◽  
Sbf Solution ◽  
The Impact

In most biphasic composite systems consisting of sol-gel derived bioactive glass and a second system that is usually used as a reinforcing agent, thorough stirring is necessary to prevent the precipitation of the grains of the second system. Consequently, the aim of this work is to investigate the impact of various stirring rates on the crystallinity and bioactivity of a bioactive glass in the system 58S. Sol-gel-derived bioactive glass (58S) was produced as described in literature. During the gelation, stirring rates of 0, 200, 400, 600 and 800 rpms were applied producing, respectively, the corresponding glass powders. The in vitro bioactivity of the powders was tested in Simulated Body Fluid (SBF) for various immersion times, while the solution was renewed after 6h, 24h and then every 2 days. Fourier Transform Infrared Spectroscopy (FTIR), Scanning Electron Microscopy (SEM) and X-ray Diffractometry (XRD) were used to characterize all materials before and after immersion in SBF solution. FTIR and XRD measurements of all powders revealed mainly the formation of an amorphous glass, while the main crystalline phase was identified to be Ca2SiO4. After immersion in SBF solution for 12h, SEM microphotographs revealed apatite formation on the surface of all samples, while FTIR and XRD confirmed the aforementioned findings. Furthermore, since EDS analysis proved a mean molar Ca/P ratio of about1.7 after 6 days of immersion of all samples- besides those stirred at 400 and 600rpm- it can be assumed that a thick apatite layer was formed covering the whole surface.

Synthesis of Magnetic TiO2 Particles for a Recoverable Application on Water Treatment

2011 ◽  
Vol 255-260 ◽  
pp. 2710-2713 ◽  
Author(s):  
Chih Hsiu Shen ◽  
Yu Jie Chang ◽  
Shang Lien Lo
Keyword(s):  
Water Treatment ◽  
Sol Gel ◽  
Good Alternative ◽  
High Specific Surface Area ◽  
Alkaline Condition ◽  
Titanium Tetraisopropoxide ◽  
Treated Water ◽  
Potential Applications ◽  
Magnetite Particles ◽  
Co Precipitation

The magnetic photocatalysts (MPCs) can provide both a high specific surface area and an alternative for recovering used catalyst from treated water by the application of a magnetic field. In this study, the Fe3O4particles were synthesized by co-precipitation under alkaline condition. After annealing, the suspension of magnetite particles can be separated by magnet. The magnetite particles were dried and then mixed with TTIP (titanium tetraisopropoxide) for sol-gel method. The MPCs were then achieved after dried and calcined in 300°C. The MPCs synthesized in this study can be separated from treated water by a simple magnet. The photocatalytic abilities of synthesized MPCs were evaluated by measuring the residual methylene blue (MB) amounts after irradiation under a light intensity of 1.0 mW/cm2at 365 nm. The results showed that the synthesized MPCs had good crystallinity of anatase and magnetite. The MPCs can be separated by a simple magnet and did not reduce the photocatalytic abilities significantly. With the advantages of reusability, durability, and separability the synthesized MPCs in this study appear a good alternative for water treatment and widely other potential applications. A MPC with an optimal Fe/Ti ratio and smaller particle size is expected to perform a more practical alternative on water treatment in the future.

scholarly journals Tartrazine degradation by supported TiO2on magnetic particles

2015 ◽  
Vol 20 (3) ◽  
pp. 668-675 ◽  
Author(s):  
Carla Lorena Heredia ◽  
dgrado Ling Sham ◽  
lsa Mónica Farfán-Torres
Keyword(s):  
Food Industry ◽  
Magnetic Particles ◽  
Magnetic Beads ◽  
Sol Gel ◽  
Nitrogen Adsorption ◽  
Bet Surface Area ◽  
Scanning Electronic Microscopy ◽  
Magnetic Photocatalyst ◽  
Magnetite Particles ◽  
Tio2 Phase

ABSTRACTMagnetic beads were obtained by dropping a solution of sodium alginate containing magnetite particles into a CaCl2 solution. TiO2anatase particles were synthetized by a sol-gel method at low temperature (75 °C), and were supported on magnetic beads to obtain the magnetic photocatalyst, MC. Magnetite particles and magnetic photocatalyst were characterized by nitrogen adsorption (BET, surface area), their morphology observed by scanning electronic microscopy (SEM) and TiO2 phase was analyzed by means of Raman spectroscopy. The photocatalytic activity of MC was evaluated on tartrazine degradation, highly used in food industry, at two different concentrations. Finally, MC stability was evaluated by reusability assays in several subsequent cycles. Results showed a good photocatalytic response for tartrazine degradation, especially at low concentration, easy recuperation and appropriate perform in the reusability of MC.

Iron Oxide and Oxide-Hydroxide Nanoparticles in Organic-Inorganic Matrices

2006 ◽  
Vol 514-516 ◽  
pp. 142-146
Author(s):  
Nuno João O. Silva ◽  
Angel Millan ◽  
Vitor S. Amaral ◽  
Fernando Palacio ◽  
Lianshe Fu ◽  
...  
Keyword(s):  
Magnetite Nanoparticles ◽  
Magnetic Particles ◽  
Sol Gel ◽  
Hybrid Structure ◽  
Ammonia Solution ◽  
Blocking Temperature ◽  
Hybrid Matrix ◽  
Sol Gel Process ◽  
Magnetite Particles ◽  
Size Controlled

Nanometric ferrihydrite, maghemite and magnetite particles formed within an organicinorganic hybrid matrix were obtained by the sol-gel process. In contrast to precipitation techniques, sol-gel process appears as suitable way to achieve size-controlled nanoscopic magnetic particles anchored in a hybrid structure. The hybrid matrix here reported, named di-ureasil, is composed of poly(oxyethylene) chains grafted to siloxane groups by means of urea cross-linkages. The formation of ferrihydrite particles was achieved incorporating iron nitrate during the sol-gel process, at low pH. The formation of maghemite takes place after the incorporation of a mixture of Fe3+ and Fe2+ ions and treatment with an ammonia solution, after the sol-gel process. Magnetite nanoparticles are formed after the incorporation of Fe2+ ions and treatment with ammonia at 80°C. The AC magnetic susceptibility shows thermal irreversibility with a blocking temperature TB≈13K and ≈25K depending on frequency for the ferrihydrite and maghemite particles, respectively. The magnetite nanoparticles are blocked at room temperature. Above the irreversibility the magnetization of ferrihydrite and maghemite follows a Langevin function modified with a linear term, as found in antiferromagnetic and ferrimagnetic particles.

scholarly journals A Comparative Study on the Properties of Potentially Bioactive Glasses Obtained by Sol-Gel Technique and by Melting Mixtures of Oxides

2017 ◽  
Vol 15 (13) ◽  
pp. 18-24
Author(s):  
Daniela Avram ◽  
Dan Ungureanu ◽  
Nicolae Angelescu ◽  
José Barroso de Aguiar
Keyword(s):  
Mechanical Energy ◽  
Sol Gel ◽  
Diffraction Method ◽  
Sem Analysis ◽  
Thin Layers ◽  
Apatite Formation ◽  
Before And After ◽  
Gel Technique ◽  
The Fourier Transform

AbstractPhosphocalcic glasses, based on ternary system SiO2 - CaO- P2O5 and those doped with copper (SiO2 – CaO - P2O5 - Cu2O) can be obtained by the traditional method of sub-cooling melts or modern methods such as process that uses mechanical energy, neutrons action, deposition in thin layers or by sol-gel technique. This paper shows the experimental results of three compositional phosphocalcic glasses: 50% SiO2 - 43% CaO - 7% P2O5, 50% SiO2 - 38% CaO - 7% P2O5 - 5% Cu2O obtained through sol-gel method and 45% SiO2 - 22.5% CaO - 22.5 Na2O - 5% P2O5 - 5% Cu2O obtained by melting. In order to study their bioactivity, the three compositions were structural analyzed by X-ray diffraction method. In this case the apatite formation was highlighted after soaked in simulated body fluid, but also other compounds (CaCO3 and CuO) resulting from the same process were observed. In case of the melting glass apatite formation has not been highlighted. The functional groups present in the structure of glasses before and after soaking (PO43−, CO32− and HO−) were highlighted by the Fourier Transform Infrared Spectroscopy (FTIR). The elemental chemical composition was confirmed by elemental analysis WD-XRF. The morphology of sol-gel glass powders was revealed by SEM analysis. All glass compositions were tested in terms of antibacterial activity in vitro.

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