In Vitro Evaluation of Hydroxyapatite-Containing Glass Coating on Zirconia

2011 ◽  
Vol 493-494 ◽  
pp. 7-10
Author(s):  
Daisuke Yamashita ◽  
Makoto Noda ◽  
Miho Machigashira ◽  
Motoharu Miyamoto ◽  
Hironobu Takeuchi ◽  
...  

The aim of this study was to investigate the response of osteoblast-like cells (MC3T3-E1) to the surface of hydroxyapatite-containing glass coating on zirconia (HA-G-Zr) in comparison to yttria stabilized zirconia (Y-TZP). The MC3T3-E1 cells were cultured on HA-G-Zr and Y-TZP specimens in 24-well tissue culture plates. Surface properties were evaluated by X-ray diffractometry, Fourier tranfer infrared microscopy (FT-IR) and scanning electron microscopy (SEM). Cell proliferation in each well was measured by MTT assay. Cell morphology was observed by SEM. Cell differentiation was evaluated by alkaline phosphatase (ALP) activity and osteocalcin levels. After the glass coating on Y-TZP, X-ray diffraction peaks due to hydroxyapatite (HA) were observed clearly. HA-G-Zr appeared on surface of uneven and roughened state, wherein microcracks on the microns in width and many voids of several microns in size were present. Time-dependent proliferation and differentiation of MC3T3-E1 cells were found in all the specimens. MC3T3-E1 cells on HA-G-Zr plates showed higher differentiation than Y-TZP. These results demonstrated that HA-G-Zr showed better cellular biocompatibility than Y-TZP.

2020 ◽  
Vol 38 (4A) ◽  
pp. 491-500
Author(s):  
Abeer F. Al-Attar ◽  
Saad B. H. Farid ◽  
Fadhil A. Hashim

In this work, Yttria (Y2O3) was successfully doped into tetragonal 3mol% yttria stabilized Zirconia (3YSZ) by high energy-mechanical milling to synthesize 8mol% yttria stabilized Zirconia (8YSZ) used as an electrolyte for high temperature solid oxide fuel cells (HT-SOFC). This work aims to evaluate the densification and ionic conductivity of the sintered electrolytes at 1650°C. The bulk density was measured according to ASTM C373-17. The powder morphology and the microstructure of the sintered electrolytes were analyzed via Field Emission Scanning Electron Microscopy (FESEM). The chemical analysis was obtained with Energy-dispersive X-ray spectroscopy (EDS). Also, X-ray diffraction (XRD) was used to obtain structural information of the starting materials and the sintered electrolytes. The ionic conductivity was obtained through electrochemical impedance spectroscopy (EIS) in the air as a function of temperatures at a frequency range of 100(mHz)-100(kHz). It is found that the 3YSZ has a higher density than the 8YSZ. The impedance analysis showed that the ionic conductivity of the prepared 8YSZ at 800°C is0.906 (S.cm) and it was 0.214(S.cm) of the 3YSZ. Besides, 8YSZ has a lower activation energy 0.774(eV) than that of the 3YSZ 0.901(eV). Thus, the prepared 8YSZ can be nominated as an electrolyte for the HT-SOFC.


Author(s):  
Erdoğan Karip ◽  
Mehtap Muratoğlu

People are exposed to different kinds of diseases or various accidents in life. Hydroxyapatite (HA) has been widely employed for bone treatment applications. In this study, HA was extracted from sheep bones. Bio-composites were doped with 1, 5, and 10 wt.% of expanded perlite and 5 wt.% of ZrO2–MgO-P2O5. The bio-composites were prepared by the cold isostatic pressing method (250 MPa) and sintered at 900°C for 1 h. In order to evaluate the characteristics of the bio-composites, microhardness, density, X-ray diffraction (XRD), Fourier transform infra-red spectroscopy (FT-IR), scanning electron microscopy (SEM), and energy dispersive spectroscopy (EDS) analyses were carried out on them. Additionally, the specimens whose characteristics were determined were kept in synthetic body fluid (SBF), and their in vitro behavior was examined. As a result, it was observed that microhardness increased as both the weight and the grain size of the expanded perlite were increased. Calcium silicate, tri-calcium phosphate, and hydroxyapatite were observed in the XRD analysis of all samples, and the formation of apatite structures was increased by addition of ZrO2–MgO–P2O5.


2010 ◽  
Vol 428-429 ◽  
pp. 126-131
Author(s):  
Wei Zhong Lu ◽  
Chun Wei ◽  
Qui Shan Gao

Polymethylene bis(p-hydroxybenzoates) were prepared from methyl p-hydroxybenzoate and different diols by melted transesterification reaction. Three liquid crystalline polyesters were synthesized from terephthaloyl dichloride and polymethylene bis(p-hydroxybenzoates). Its structure, morphology and properties were characterized by Ubbelohde viscometer, Fourier transform infrared spectroscopy (FT-IR), Differential scanning calorimetry (DSC), polarized optical microscopy (POM) with a hot stage, and wide-angle X-ray diffraction (WAXD). Results indicated that the intrinsic viscosities were between 0.088 and 0.210 dL/g. Optical microscopy showed that the TLCP has a highly threaded liquid crystalline texture and a high birefringent schlieren texture character of nematic phase and has wider mesophase temperature ranges for all polyesters. DSC analysis were found that the melting point (Tm), isotropic temperature (Ti) of TLCPs decreased and the temperature range of the liquid crystalline phase became wider with increased number of methylene spacers in the polyester. The WAXD results showed that TLCPs owned two strong diffraction peaks at 2θ near 19° and 23°.


2015 ◽  
Vol 638 ◽  
pp. 67-72
Author(s):  
Ana Maria Salantiu ◽  
Florin Popa ◽  
Petru Pascuta ◽  
Olga Soritau ◽  
Noemi Dirzu ◽  
...  

This work aims to investigate the influence of surface conditioning of porous Ti for enhancing its biological activity, as assessed by in vitro stem cell testing. Porous Ti samples with an average porosity of 32% were processed by Powder Metallurgy with dextrin as a space holder. The samples were subjected to H2O2 treatment to form an enhanced TiO2 film, followed by a heat treatment at 400°C and 600°C aiming to the crystallization of the as-formed amorphous titanium oxide. Samples characterization was performed by Scanning Electron Microscopy (SEM), Fourier Transform Infrared Spectroscopy (FT-IR) and X-Ray Diffraction (XRD). The treated surfaces revealed to be made of both anatase and rutile TiO2, with groove–shaped structure and cracks on the surface of the TiO2 film. The intrinsic biocompatibility of the chemically modified porous Ti surfaces was assessed in vitro. In our cell culture tests, stem cells were found to attach and proliferate better on the chemically treated Ti surfaces compared to the control untreated Ti surfaces.


2021 ◽  
Vol 21 (11) ◽  
pp. 5592-5602
Author(s):  
Samira Almasi ◽  
Ali Mohammad Rashidi

The effect of the yttria-stabilized zirconia (YSZ) nanoparticle loading in an electro-less bath was considered as one of the vital synthesis variables for control Ni content and microstructure of prepared nanocomposite particles, which are two crucial factors to achieving high-performance SOFC anode. Nanocomposite particles were prepared using a simple electroless method without any expensive pretreatment of sensitizing by Sn2+ ions as well as activating by Pd2+ ions that are usually used to apply nickel coating on the surface of a non-conductive substrate. The process was performed by adding YSZ nanoparticles into NaOH solution, separating them from the solution by the centrifugal method, then providing several water-based nanofluids with different concentrations of activated YSZ nanoparticles, mixing them with NiCI2 solution, followed by adding the hydrazine and then NaOH solution. X-ray diffraction and scanning electron microscopy coupled with energy dispersive X-ray analysis were used to analyze the prepared nanocomposite particles. It is observed that after adding YSZ nanoparticles into the NaOH solution, the pH of the solution varied gradually from a starting pH of 10.2 to 9. Also, by increasing the YSZ nanoparticles loading in the electroless bath from 76 mg/l to 126 mg/l, the grain size of Ni deposits, the Ni content and the average size of the prepared nanocomposite particles decreased. The electrochemical mechanism previously proposed for the nickel ion reduction was modified, and a novel analytical model was proposed for variation of the efficiency of Ni deposition with YSZ nanoparticles loading.


2019 ◽  
Vol 41 (6) ◽  
pp. 1090-1090
Author(s):  
Mehmet Poyraz Mehmet Poyraz ◽  
Musa Sari Musa Sari ◽  
Halil Berber Halil Berber ◽  
Nursenem Karaca and Fatih Demirci Nursenem Karaca and Fatih Demirci

A new Schiff base, namely 2-methoxy-6-((2-(4 nitrophenyl) hydrazineylidene) methyl)phenol was synthesized and characterized by melting points, elemental analysis, thermogravimetric analysis and spectroscopic techniques (FT-IR, 1H-NMR and UV-VIS spectra). The chemical structure of compound was further confirmed by single crystal structural X-ray diffraction. The Schiff base is crystallized in the triclinic space group P-1. In the crystal, molecules are linked by O-H…O hydrogen bonds between the hydroxy “-O-” atom and the methoxy “-O-” atom. Furthermore, the synthesized Schiff base was tested for the in vitro anticandidal activities using CLSI broth microdilution method against human pathogenic Candida albicans, C. parapsilosis and C. krusei standard strains. In the anticandidal activity test results, the new Schiff base was found to be effective at 1 mg/mL - 0.25 mg/mL concentrations. (The last line omitted) (The sentence marked in red will be deleted)


1991 ◽  
Vol 05 (27) ◽  
pp. 1829-1835 ◽  
Author(s):  
Q.X. SU ◽  
L. LI ◽  
Y.Y. ZHAO ◽  
Y.Z. ZHANG ◽  
P. XU

Yttria-stabilized Zirconia(YSZ) films were deposited on (100)Si substrates by R.F. magnetron sputtering method. X-ray diffraction analysis showed that the best YSZ films were cubic in structure and was grown epitaxially with (100) orientation. The (200) peak of YSZ films was 0.8° of the full width at half of the maximum, X-ray diffraction based on Seemann-Bohlin focusing geometry showed no peaks. The morphology of the YSZ films was observed by scanning electron microscopy. The effects of the processing conditions (such as substrate temperature, oxygen partial pressure, etc.) on the structure of the film were also discussed.


2018 ◽  
Vol 2018 ◽  
pp. 1-8 ◽  
Author(s):  
Samuel Tetteh ◽  
Andrews Quashie ◽  
Michael Akrofi Anang

Three clay samples (E1, E2, and C1) extracted from different parts of Ghana have been purified by sedimentation. The samples were further characterized by powder X-ray diffraction (PXRD), Fourier transform infrared spectroscopy (FT-IR), scanning electron microscopy (SEM), cation exchange capacity (CEC), and point of zero charge (pHpzc). PXRD and FT-IR data revealed the samples to be predominantly muscovite clay with percentages ranging from 82.71 to 91.33%. The surfaces were mostly cationic with pHpzc ranging from 5.58 to 6.40. Morphological studies by SEM confirmed the crystalline nature of the surfaces which is suitable for adsorption studies. Time-dependent adsorption studies show that C1 is a good candidate for the adsorption of chlorophenols, methyl orange, and Eriochrome Black T.


2019 ◽  
Vol 2019 ◽  
pp. 1-8
Author(s):  
Wei Xiong ◽  
Yue-kun Shen ◽  
Peng Dong ◽  
Ying Xiao ◽  
Xiong-qing Huang ◽  
...  

Sustained release of anesthesia has shown great promise in the treatment of chronic pain in patients. In this research, we used neutralized ropivacaine as an anesthesia and poly(ε-caprolactone) (PCL) with different architectures to systematically study how these architectures affect the release of ropivacaine. After optimizing the parameters of the preparation of microspheres, ropivacaine-loaded 1-PCL microspheres and 4-PCL microspheres were obtained. Fourier Transform infrared spectra (FT-IR) and X-ray diffraction spectra (XRD) confirmed that ropivacaine was encapsulated within the microsphere rather than inserted on the surface of the microsphere. Ropivacaine was found to be buried deeper in the 1-PCL microsphere than in the 4-PCL microsphere. In vitro release assay revealed that small crystalline grains interfered with ropivacaine release in 4-PCL microspheres during the initial release period, but then two kinds of microspheres showed a similar ropivacaine release rate. We basically proved that the architecture of PCL has a negligible effect on ropivacaine release. Cell proliferation test revealed that the release of products from the microspheres resulted in insignificant toxicity towards mammalian cells.


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