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Neslihan Alemdar - One of the best experts on this subject based on the ideXlab platform.
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Production of ciprofloxacin loaded chitosan/gelatin/Bone Ash wound dressing with improved mechanical properties
Carbohydrate Polymers, 2019Co-Authors: Begüm Evranos, Didem Aycan, Neslihan AlemdarAbstract:Abstract Polymeric films with enhanced mechanical performance were fabricated by incorporation of Bone Ash (BA) at various concentrations (0 to 25 v. %) into chitosan/gelatin (CTS/GEL) polymeric structure as a wound healing-dressing. The test results for mechanical performance of polymeric films proved that the encapsulation of BA into the polymeric films enhances the elastic modulus and tensile strength of polymeric films significantly. Oxygen permeability and water vapor transmission rate (WVTR) of films were also improved by BA reinforcement. Ciprofloxacin was chosen as the antibacterial model drug. The release of ciprofloxacin was provided in a more controlled manner at pH 7.4 owing to the incorporation of Bone Ash into the polymeric films. Also, drug loaded films showed great antibacterial activity against Escherichia coli and Bacillus subtilis bacteria. The results prove that ciprofloxacin loaded BA reinforced CTS/GEL composite films are potentially applicable in controlled drug delivery as wound dressings.
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development of ph responsive chitosan based hydrogel modified with Bone Ash for controlled release of amoxicillin
Carbohydrate Polymers, 2017Co-Authors: Didem Aycan, Neslihan AlemdarAbstract:Abstract In present study, Bone Ash-reinforced chitosan-based hydrogels were obtained by encapsulation of Bone Ash into the hydrogel structure which was fabricated by photopolymerization of chitosan-grafted-glycidyl methacrylate (CTS-g-GMA) and poly(ethylene glycol)diacrylate (PEGDA) under the UV light. Hydrogels were characterized by ATR-FTIR, SEM and XRD analyses. Mechanical performance of the hydrogels was determined by universal mechanical tester. Cytotoxicity tests for hydrogels were conducted with L929 cell lines to determine cellular compatibility. Swelling tests were carried out to investigate the water uptake capacity of hydrogels. Amoxicillin which could be used for treatment of gastric ulcer was selected as the model drug. The release of amoxicillin was provided at simulated gastric (pH: 1.2) and intestinal media (pH: 7.4) in efficient and controlled manner. All results visualized that the obtained pH-sensitive chitosan-based hydrogel with enhanced mechanical properties could be a potential candidate as a drug carrier for treatment of gastric ulcer in the future applications.
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fabrication of a novel Bone Ash reinforced gelatin alginate hyaluronic acid composite film for controlled drug delivery
Carbohydrate Polymers, 2016Co-Authors: Neslihan AlemdarAbstract:Abstract In this study, a novel pH-sensitive composite film with enhanced thermal and mechanical properties was prepared by the incorporation of Bone Ash at varying concentrations from 0 to 10 v.% into gelatin/sodium alginate/hyaluronic acid (Gel/SA/HyA) polymeric structure for colon-specific drug delivery system. Films were characterized by FT-IR, SEM, and XRD analyses. Thermal and mechanical performances of films were determined by DSC, TGA and universal mechanical tester, respectively. Results proved that thermal stability and mechanical properties of Bone Ash-reinforced composite films improved significantly with respect to that of neat Gel/SA/HyA film. Cytotoxicity assay for composite films was carried out by using L929 cells. Water uptake capacity of films was determined by swelling test. Herein, release experiments of 5-Fluorouracil (5-FU) were performed in two different solutions (pH 2.1 and 7.4). The results assured that Gel/SA/HyA film containing BA could be considered as a potential biomaterial for controlled drug delivery systems.
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Fabrication of a novel Bone Ash-reinforced gelatin/alginate/hyaluronic acid composite film for controlled drug delivery
Carbohydrate Polymers, 2016Co-Authors: Neslihan AlemdarAbstract:Abstract In this study, a novel pH-sensitive composite film with enhanced thermal and mechanical properties was prepared by the incorporation of Bone Ash at varying concentrations from 0 to 10 v.% into gelatin/sodium alginate/hyaluronic acid (Gel/SA/HyA) polymeric structure for colon-specific drug delivery system. Films were characterized by FT-IR, SEM, and XRD analyses. Thermal and mechanical performances of films were determined by DSC, TGA and universal mechanical tester, respectively. Results proved that thermal stability and mechanical properties of Bone Ash-reinforced composite films improved significantly with respect to that of neat Gel/SA/HyA film. Cytotoxicity assay for composite films was carried out by using L929 cells. Water uptake capacity of films was determined by swelling test. Herein, release experiments of 5-Fluorouracil (5-FU) were performed in two different solutions (pH 2.1 and 7.4). The results assured that Gel/SA/HyA film containing BA could be considered as a potential biomaterial for controlled drug delivery systems.
T Altzitzoglou - One of the best experts on this subject based on the ideXlab platform.
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measurement of low level radioactivity in Bone Ash
Journal of Environmental Radioactivity, 1999Co-Authors: R Pilvio, J J Larosa, D Mouchel, R Wordel, M Bickel, T AltzitzoglouAbstract:Abstract Bone is a critical organ for the accumulation of many radionuclides including 90 Sr and the actinides. The National Institute of Standards and Technology (0NIST) has prepared Bone Ash samples with a view to producing a standard reference material. The Institute for Reference Materials and Measurements (IRMM) participated in the analysis for the certification of the radionuclide concentrations in the Bone Ash. This article describes the assaying of the actinides, 90 Sr, 210 Pb and 226 Ra activity concentrations. A radiochemical procedure based on extraction chromatography has been developed to separate these radionuclides from the Bone Ash. The activity concentrations of the actinides, 210 Pb and 226 Ra have been measured using gamma-ray spectrometry and alpha-particle spectrometry and that of 90 Sr using low-level liquid scintillation counting.
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Measurement of 90Sr in Bone Ash.
Applied radiation and isotopes : including data instrumentation and methods for use in agriculture industry and medicine, 1998Co-Authors: T Altzitzoglou, J J Larosa, C NichollAbstract:Bone is a critical organ for the accumulation of many radionuclides, including 90Sr. A Bone Ash has been prepared by NIST to become a standard reference material and the assaying of the 90Sr activity concentration is reported. A radiochemical procedure, based on extraction chromatography using a crown ether, has been developed to separate Sr from the Bone Ash. The natural Sr content of the Bone Ash has been determined by isotope dilution inductively coupled plasma mass spectrometry. The 90Sr activity concentration has been measured by low-level liquid scintillation counting.
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Development of the NIST Bone Ash standard reference material for environmental radioactivity measurement.
Applied radiation and isotopes : including data instrumentation and methods for use in agriculture industry and medicine, 1998Co-Authors: T Altzitzoglou, D Arnold, D Cavadore, M Korun, H Wershofen, Y Takata, A YoungAbstract:The Bone Ash standard reference material (SRM), a blend of 4% contaminated human Bone and 96% diluent bovine Bone, has been developed for radiochemical method validation and quality control for radio-Bone analysis. The massic activities of 90Sr, 226Ra, 230Th, 232Th, 234U, 235U, 238U, 238Pu, (239 + 240)Pu and (243 + 244)Cm were certified using a variety of radiochemical procedures and detection methods. Measurements confirmed undetectable radionuclide heterogeneity down to a sample size of 5 g. thereby implying adequate blending of particulate materials with dilution factors of up to 17,900. The results among most of the intercomparison laboratories and their methods were consistent. Disequilibrium was observed for decay chains: 234U(0.67 mBq/g)-230Th(0.47 mBq/g)-226Ra(15.1 mBq/g)-210Pb(23 mBq/g)-210Po(13 mBq/g) and 232Th(0.99 mBq/g)-228 Ra(6.1 mBq/g)-228Th(7.1 mBq/g). The disequilibria were the results of mixing occupationally contaminated human Bone with natural bovine Bone and the fractionation during internal biological processes. The massic activity of 210Pb, 228Th and 241Am were not certified because of insufficient 228Ra and 241Pu data and lack of knowledge in how 222Rn and its daughters will be fractionated in the SRM bottle over time.
Douglas Gouvea - One of the best experts on this subject based on the ideXlab platform.
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using Bone Ash as an additive in porcelain sintering
Ceramics International, 2015Co-Authors: Douglas Gouvea, Henrique Kahn, Taisa Tisse Kaneko, Edilene De Souza Conceicao, Juliana Livi AntoniassiAbstract:Abstract Calcined bovine Bone (CBB) is generally used to manufacture high-quality porcelain known as Bone china. In these products, the amount of Bone Ash is about 50%. However, it is known that CBB, in small quantities added to raw materials such as feldspars, can reduce the liquidus temperature and thus promote liquid-phase sintering. The purpose of this study was to evaluate the potential use of Bone Ash as a sintering promoter of porcelain made by a classical triaxial system. Hard porcelain was prepared with 0, 1, 2, and 5 wt% CBB and sintered at temperatures ranging from 1100 to 1400 °C. For the sample containing 2% CBB, the sintering temperature was reduced by 50 °C relative to 0% CBB, while the sample’s tensile strength was the highest among all samples. Two mechanisms could be observed during porcelain sintering depending on CBB quantities: for 1 and 2% of CBB, the mullite formation determined the final shrinkage without changes on initial sintering temperatures; for 5% the initial sintering temperature was decreased by liquid formation.
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surface modification of bovine Bone Ash prepared by milling and acid wAshing process
Ceramics International, 2009Co-Authors: Douglas Gouvea, Gerardo Augusto Vera Alatrista, S L M Brito, Ricardo H R Castro, Henrique KahnAbstract:Abstract Bovine Bone Ash is the main raw material for fabrication of Bone china, a special kind of porcelain that has visual and mechanical advantages when compared to usual porcelains. The properties of Bone china are highly dependent on the characteristics of the Bone Ash. However, despite a relatively common product, the science behind formulations and accepted fabrication procedures for Bone china is not completely understood and deserves attention for future processing optimizations. In this paper, the influence of the preparation steps (firing, milling, and wAshing of the Bones) on the physicochemical properties of Bone Ash particles was investigated. Bone powders heat-treated at temperatures varying from 700 to 1000 °C were wAshed and milled. The obtained materials were analyzed in terms of particle size distribution, chemical composition, density, specific surface area, FTIR spectroscopy, dynamic electrophoretic mobility, crystalline phases and scanning electron microscopy. The results indicated that Bone Ash does not significantly change in terms of chemistry and physical features at calcination temperatures above 700 °C. After wAshing in special conditions, one could only observe hydroxyapatite in the diffraction pattern. By FTIR it was observed that carbonate seems to be mainly concentrated on the surface of the powders. Since this compound can influence in the dispersion stability, and consequently in the quality of the final Bone china product, and considering optimal wAshing parameters based on the dynamic electrophoretic mobility results, we describe a procedure for surface cleaning.
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effect of calcination temperature on the properties of bovine Bone Ash for the fabrication of Bone china
Cerâmica, 2007Co-Authors: Douglas Gouvea, Gerardo Augusto Vera Alatrista, S Bernard, S M TofolliAbstract:Calcined bovine Bones comprise the main raw material for the fabrication of Bone China (more than 50 wt.%). This special kind of porcelain has never been produced in Brazil. In this paper, the influence of the following preparation steps: firing, grinding, and wAshing of the Bones, on the physicochemical characteristics of the obtained Bone Ash particles was investigated. Powders calcined at temperatures between 700 and 1000 oC, wAshed and ground, were analyzed in terms of their particle size distribution, chemical composition (X-ray fluorescence), density (He picnometry), specific surface area (BET method), infrared spectroscopy (FTIR-DRIFT), and also in a scanning electron microscopy. The results indicated that Bones processed at different temperatures exhibit great homogeneity either in chemical terms (chemical composition and electrophoretic mobility) or in physical terms (particle size and phase composition), show slight increase in particle size with increasing firing temperatures and must be calcined under oxidizing atmospheres in order to develop good processing characteristics.
Mohammad Javad Amiri - One of the best experts on this subject based on the ideXlab platform.
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Numerical simulation of Cd(II) removal by ostrich Bone Ash supported nanoscale zero-valent iron in a fixed-bed column system: Utilization of unsteady advection-dispersion-adsorption equation
Journal of water process engineering, 2018Co-Authors: Mohammad Javad Amiri, Reza RoohiAbstract:Abstract A rigorous model, based on the numerical simulation of one-dimensional, unsteady of advection-dispersion-adsorption equation (UADAE) solved by the implicit finite difference method (IFDM), has been employed to simulate the dynamic adsorption of Cd(II) ions on ostrich Bone Ash (OBA)/nanoscale zerovalent iron particles (nZVI) composite (OBA/nZVI) in a fixed-bed column system. The accuracy of the numerical model was assessed by employing three criteria: mean residual error (MRE), normalized root mean square error (NRMSE) and coefficient of determination (R 2 ). The numerical model tracked the observed values very closely (R 2 = 0.9698). It was found that the numerical model had the excellent performance to simulate breakthrough curves (BTC) (NRMSE = 7.66%) and it tended to overestimate the BTC very slightly (MRE = 0.0029). The sensitivity analysis indicated that the axial dispersion coefficient ( D ) had more significant impact on the column dynamic simulation. Therefore, it is possible to describe the adsorption process for wastewater treatment systems in a more cost-effective and easier way with the suggested model application. The results obtained from SEM and XRD analyses confirmed that the OBA/nZVI composite preserved its capabilities even after one year of storage under room conditions. The results also obtained from XPS technique confirmed that the removal mechanism of Cd(II) ions, which have the standard reduction potential very close to that of Fe, is the sorption/surface complex formation without reduction of Cd(II) to Cd° by nZVI.
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adsorption reduction of hg ii and pb ii from aqueous solutions by using Bone Ash nzvi composite effects of aging time fe loading quantity and co existing ions
Environmental Science and Pollution Research, 2018Co-Authors: Mohammad Javad Amiri, Jahangir Abedikoupai, Saeid EslamianAbstract:In this research, a versatile and highly efficient method for the stabilization of nanoscale zerovalent iron particles (nZVI) on the surface of ostrich Bone Ash (OBA) was presented as a novel inorganic adsorbent (OBA/nZVI) for the removal of Hg(II) and Pb(II) ions from aqueous solutions, even after 1 year of storage under room conditions. The removal behavior of the OBA/nZVI was assessed as a function of the initial pH, contact time, initial pollutants concentration, temperature, amount of adsorbent, effect of competitive metal ions, and ionic strength. The synthesized adsorbent was characterized by several techniques including N2 adsorption at - 196 °C, FT-IR spectroscopy, scanning electron microscopy, X-ray diffraction, and zeta potential. The results confirmed that the OBA is a good candidate as support of nZVI. The maxima adsorption capacity for Hg(II) and Pb(II) ions found from experimental results were 170 and 160 mg g-1, when the loading quantities of Fe were 20%. The equilibrium sorption data obeyed a Langmuir-Freundlich isotherm type model. The kinetic data of the adsorption followed the mechanism of the pseudo-second-order model. The thermodynamic experiments indicated that the removal of metal ions were feasible, endothermic, and spontaneous. It can be found that fresh and aged OBA/nZVI maintained its usability even after five cycles in the order: fresh (OBA/nZVI)-Hg(II) > fresh (OBA/nZVI)-Pb(II) > aged (OBA/nZVI)-Hg(II) > aged (OBA/nZVI)-Pb(II), which indicate that OBA/nZVI can be regenerated as adsorbent. The existence of Fe in the OBA/nZVI was proved by SEM-EDX results and X-ray diffraction analysis also confirmed adsorption/reduction of some of the Hg(II) to Hg0 and Pb(II) to Pb0.
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adsorption of hg ii and pb ii ions by nanoscale zero valent iron supported on ostrich Bone Ash in a fixed bed column system
Water Science and Technology, 2017Co-Authors: Mohammad Javad Amiri, Jahangir Abedikoupai, Sayed Saeid EslamianAbstract:In this research, ostrich Bone Ash (OBA) was modified with nanoscale zerovalent iron (nZVI) particles and applied as a novel composite adsorbent (OBA/nZVI) for dynamic adsorption/reduction of Hg(II) and Pb(II) ions in a fixed-bed column system. Entrapment of nZVI in OBA beads barricades the particles from oxidation and aggregation. The dynamic behavior of metal ions removal by OBA/nZVI was assessed as a function of inlet flow rates, bed height, initial pollutants concentration and pH. The synthesized OBA/nZVI composite was characterized by several physicochemical techniques. Increase in pH and bed height and decrease in flow rates and initial metal concentration resulted in delay of breakthrough time. OBA breakthrough profile is sharper than the OBA/nZVI breakthrough curve for both metal ions and the breakthrough times increase in the order OBA/nZVI-Hg(II) > OBA/nZVI-Pb(II) > OBA-Pb(II) > OBA-Hg(II). Based on the experiment results, redox reaction is expected to occur to a certain extent, as the standard reduction potentials of Hg(II) and Pb(II) are more than that of Fe(II). From a practical point of view, the OBA/nZVI could be applied as a material to remove Hg(II) and Pb(II) ions from natural surface and ground water with a pH value of 5-9.
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modeling pb ii adsorption from aqueous solution by ostrich Bone Ash using adaptive neural based fuzzy inference system
Journal of Environmental Science and Health Part A-toxic\ hazardous Substances & Environmental Engineering, 2013Co-Authors: Mohammad Javad Amiri, Jahangir Abedikoupai, Sayed Saeid Eslamian, Sayed F Mousavi, Hasti HasheminejadAbstract:To evaluate the performance of Adaptive Neural-Based Fuzzy Inference System (ANFIS) model in estimating the efficiency of Pb (II) ions removal from aqueous solution by ostrich Bone Ash, a batch experiment was conducted. Five operational parameters including adsorbent dosage (Cs), initial concentration of Pb (II) ions (Co), initial pH, temperature (T) and contact time (t) were taken as the input data and the adsorption efficiency (AE) of Bone Ash as the output. Based on the 31 different structures, 5 ANFIS models were tested against the measured adsorption efficiency to assess the accuracy of each model. The results showed that ANFIS5, which used all input parameters, was the most accurate (RMSE = 2.65 and R2 = 0.95) and ANFIS1, which used only the contact time input, was the worst (RMSE = 14.56 and R2 = 0.46). In ranking the models, ANFIS4, ANFIS3 and ANFIS2 ranked second, third and fourth, respectively. The sensitivity analysis revealed that the estimated AE is more sensitive to the contact time, followe...
Isiaka Oluwole Oladele - One of the best experts on this subject based on the ideXlab platform.
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Effect of Cow Bone Ash Particle Size Distribution on the Mechanical Properties of Cow Bone Ash-Reinforced Polyester Composites
chemistry and materials research, 2020Co-Authors: Temitope Akinyemi Adewole, Isiaka Oluwole OladeleAbstract:This research work was carried out to study the influence of cow Bone Ash particles in polyester matrix composites in order to improve the properties of polyester matrix and to provide alternative use of cow Bone which constitute a challenge to the environment especially in developing countries. Cow Bone was sourced from an abattoir, wAshed, sun dried for 4week and then carbonized. The Bone Ashes were further pulverized using the ball mill. Sieve analysis was carried out on the pulverized Bone Ash particles into particle sizes of 75?m, 106?m and 300?m. Composite materials were developed by casting into tensile, hardness and flexural tests samples using pre-determined proportions of 2, 4, 6, and 8 wt % of the cow Bone Ash. The samples after curing were striped from the moulds and were allowed to further cure at room temperature for 3 weeks before tensile, hardness and flexural tests were performed on them. The results shows that use of cow Bone Ash particles of 75,106 and 300 ????m led to the enhancement of the mechanical properties of polyester matrix. The tensile result shows that sample reinforced with 4% of particle size 300µm gave the highest value of UTS, sample with 8% of particle size 300µm Bone Ash has the highest value of tensile modulus. Flexural strength were highly enhanced with 8% of particle size 75µm has the highest value of bending strength, this shows that fine particles lead to improved strength. The best result for hardness was obtained from 6wt% 106????m cow Bone Ash-reinforced sample with a value of 87.8HV compared to the unreinforced polyester matrix with a value of 81HV. Keywords: polyester, composites, mechanical properties, cow Bone Ash.
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Development of Bone Ash and Bone Particulate Reinforced Polyester Composites for Biomedical Applications
2020Co-Authors: Isiaka Oluwole OladeleAbstract:This work was carried out to comparatively study the reinforcement efficiency of Bone Ash and Bone particles on the mechanical properties of polyester matrix composites in order to investigate the suitability of the materials as biomaterial. Cow Bone were procured from an abattoir and sun dried for 4 weeks after which it was crushed with a sledge hammer. A portion was burnt to Ashes while others were further pulverized with laboratory ball mill before the two grades were sieved using 75 μm sieve size. Bone Ash and Bone particle reinforced tensile and flexural composite samples were developed from pre-determined proportions of 2, 4, 6, and 8 %. The samples after curing were striped from the moulds and were allowed to further cure for 3 weeks before tensile and flexural tests were performed on them. The tensile test result showed that, 8 wt % Bone particle reinforced polyester composites has higher tensile properties except for modulus of elasticity where 8 wt % Bone Ash particle reinforced composites has higher value while for flexural test, Bone Ash particle reinforced composites demonstrate the best flexural properties. The results show that these materials are structurally compatible and being developed from animal fibre based particle, it will also aid the compatibility with the surface conditions as biomaterial.