In Vivo Behavior of Hydroxyapatite Evaluated by Attenuated Total Reflection Infrared Microscopy (ATR-FTIR)

2008 ◽  
Vol 396-398 ◽  
pp. 61-64 ◽  
Author(s):  
Monica Calasans-Maia ◽  
Silvia R. A. Santos ◽  
Antonella M. Rossi ◽  
José Mauro Granjeiro

The study aimed the evaluation of the effect of osseous repair in the synthetic hydroxyapatite cylinder (HA) implanted in rabbit’s tibia. Fifteen adult animals, weighing around 2.5 and 3.0 Kg, sourced by the Fluminense Federal University Animal Lab were anesthetized with spinal anesthesia, and two perforations were created in right tibia and filled with cylinders (2 x 6 mm) of HA. The animals were killed after 28 days for evaluating the HA cylinder through attenuated total reflection infrared microscopy (ATR-FTIR). The two fragments of tibia with the cylinder were collected and fixed in alcohol 70° prior to dehydration in successive alcohol solutions and then impregnated and embedded in methyl-methacrylate. Not stained neither pasted to lamina, sections of 200 µm thickness were analyzed in a Shimadzu IRPrestige-21 Automatic Infrared Microscope (AIM-8800) with ATR Objective Mirror (ATR-8800M). Prior to implantation, HA cylinder was characterized by X-Ray diffraction (XRD), Attenuated Total Reflection- Infra Red microscopy (ATR-FTIR) and X-Ray Fluorescence (XRF). After the implantation, the spectrum of the ATR-FTIR at the interface to neoformed bone was acquired. The hydroxyapatite synthesized was crystalline and stoichiometric with Ca/P ratio of 1.66, becoming carbonated after 28 days of implantation. We conclude that attenuated total reflection-Fourier transform infrared spectroscopy (ATR-FTIR) is a useful tool for biomaterial evaluation and able to detect the modification of the chemical HA cylinder pattern occurred probably by ions migration in the biological environment.

2019 ◽  
Vol 796 ◽  
pp. 80-87
Author(s):  
Akinsanya Damilare Baruwa ◽  
Esther Titilayo Akinlabi ◽  
Oluseyi Philip Oladijo ◽  
Stephen Akinwale Akinlabi ◽  
Jeff Chinn

The aim of the research is to subject the three different silanes to chemical and electrochemical investigations in other to determine the most efficient organic compound. Three types of hydrophobic silanes [Tris (Trimethylsiloxy) silyethyl] dimethylchlorosilane (Alkyl); Tridecafloro-1,1,2,2-tetrahydrooctyltrichlorosilane (FOTS) and Henicosyl-1,1,2,2-tetrahydrododecyltricholrosilane (FDDTS) are presented and investigated. The three silanes are of different composition but are deposited at the same parameters and conditions. The chemical investigation was studied through (attenuated total reflection Fourier-transform infrared (ATR-FTIR) and x-ray diffraction (XRD), while the electrochemical study was conducted through EIS using natural seawater electrolyte at room temperature. From the investigation techniques, only electrochemical impedance results show that FDDTS performed better than both Alkyl and FOTS. The chemical analysis showed the presence of hydrophobic silane on all the coated samples, and no distinction can be drawn from associated peaks.


1996 ◽  
Vol 432 ◽  
Author(s):  
Viviane V. Silva ◽  
Rosana Z. D. Fernandes

AbstractHydroxyapatite (HA), specifically, calcium hydroxyapatite, is the main inorganic compound of human bone and teeth. The utilization of synthetic powders of this material in dental and medical implants has increased in the recent days.In this paper, synthetic hydroxyapatite powder was prepared by a precipitation method, compacted and sintered at 800, 900, 1000, 1100, 1200 and 1300° C. The powder and its ceramics were analysed by X-ray diffraction, infra-red spectroscopy and scanning electron microscopy. The influence of experimental conditions on the microstructure and densification is discussed.Some measurements of the hydroxyapatite ceramics obtained in this work were compared with those of the hydroxyapatite ceramics produced from a commercial powder. It was shown that calcium hydroxyapatite is probably the only phase present for the precipitated samples sintered below 1100° C.


2016 ◽  
Vol 75 (5) ◽  
pp. 1211-1220 ◽  
Author(s):  
B. Boutra ◽  
M. Trari

The present work is devoted to the synthesis of a new photocatalyst ZnO (7.5%)/Bentonite prepared by impregnation method and its successful application for the degradation of Solophenyl Red 3BL (SR 3BL) under solar light (∼660 W/m2). The X-ray diffraction (XRD) indicates mixed phases of the nanocomposite catalyst (ZnO/Bentonite), characterized by scanning electron microscopy, X-ray fluorescence and attenuated total reflection. The optical properties confirm the presence of the Wurtzite ZnO phase with an optical gap of 3.27 eV. The catalyst dose (0.25–1 gL−1), pH solution (2.5–11) and initial dye concentration (5–75 mg/L) are optimized. The optimal pH (∼6.7) is close to the natural environment. The photodegradation yield increases with decreasing the SR 3BL concentration. The equilibrium is reached within 160 min and the data are well fitted by the Langmuir-Hinshelwood model; the SR 3BL disappearance obeys to a first-order kinetic with an apparent rate constant of 10−2 mn−1. The best yield of SR 3BL photodegradation (92%) is achieved for a concentration of 5 mg/L and a catalyst dose of 0.75 gL−1 at free pH.


2013 ◽  
Vol 47 (1) ◽  
pp. 407
Author(s):  
D. Papoulis ◽  
S. Komarneni ◽  
D. Toli ◽  
D. Panagiotaras ◽  
S. Bakalis

The synthesis as well as the characterization of small-sized TiO2 particles supported on Halloysite are presented. Hallloysite from Utah, USA as well as from Limnos, island Greece, were used to synthesize two nanocomposites for each halloysite with TiO2 to halloysite weight ratios of 80: 20 and 60:40 and compare with published data of well formed nanocomposites of intermediate proportion (70-30) that were previously studied. All nanocomposites were prepared by deposition of anatase (TiO2) on the halloysite tubes using a sol–gel method under hydrothermal treatment at 180 °C. Phase composition, particle morphology and physical properties of these samples were characterized using X-Ray Diffraction (XRD), Scanning Electron Microscopy (SEM), Attenuated Total Reflection using Fourier Transform Infrared spectroscopy (ATR-FTIR) and N2 surface area analysis by BET. Preparation of all halloysite–TiO2 nanocomposites led to the anticipated good dispersion of anatase particles on halloysite surfaces. ATR-FTIR results revealed the formation of hydrogen bonding between anatase and the outer surfaces of halloysite tubes. All halloysite-TiO2 nanocomposites largely showed interparticle mesopores of about 5.7nm and high SSAs.


2020 ◽  
Vol 23 (1) ◽  
pp. 27
Author(s):  
Rina Dewi Mayasari ◽  
Ajeng Novita Sari ◽  
Aditya Eka Mulyono ◽  
Agus Setyo Budi ◽  
Ratno Nuryadi

Pengamatan fenomena surface plasmon resonance (SPR) telah berhasil dilakukan pada ZnO nanorods yang ditumbuhkan di atas lapisan tipis emas. Sistem SPR menggunakan konfigurasi Kretschmann termodifikasi dimana permukaan prisma dideposisi dengan lapisan tipis emas dan ZnO nanorods (prisma/Au/ZnO). Penumbuhan ZnO nanorods menggunakan metode hidrotermal dengan dua tahapan, yaitu pelapisan ZnO seed dan penumbuhan rods. Waktu penumbuhan divariasikan selama 5 menit, 2 jam, dan 4 jam, pada suhu 95 °C yang diikuti dengan annealing pada suhu 500 °C selama 1 jam. Struktur ZnO dikarakterisasi dengan X-ray diffraction (XRD), field emission scanning electron microscope - energy dispersive X-ray spectroscopy (FESEM-EDS), serta diamati fenomena SPR melalui grafik attenuated total reflection (ATR). Hasil karakterisasi menunjukkan bahwa ZnO nanorods (2 jam dan 4 jam) memiliki struktur kristal heksagonal dengan distribusi ukuran diameter pada rentang 20 nm – 60 nm. Fenomena SPR hanya teramati pada nanopartikel ZnO (5 menit) pada sudut SPR (θSPR) 58,2°. Fenomena SPR tidak terlihat pada ZnO nanorods (2 jam dan 4 jam) dikarenakan panjang rods melebihi 100 nm.


2012 ◽  
Vol 1406 ◽  
Author(s):  
A. Simo ◽  
L.C. Edomwonyi-Otu ◽  
R. Madjoe ◽  
M. Maaza

ABSTRACTFacile and direct synthesis of radiative VO2 (M) plate-like is reported. The snowflake material presents superstructures plate-like aggregate with an anisotropic orientation in shape governed by V2O5 and NaOH concentration giving high surface energy liable for chemical reactions with the medium. Pure crystalline VO2 (M) has been obtained with a complete hydrothermolysis of the precursor. The morphological, structural, elemental composition, crystallinity and vibrational bands of the powders were characterized by Powder X-ray Diffraction (XRD), Scanning Electron Microscopy (SEM), Selected Area Electron Diffraction (SAED) and Fourier Transform-Attenuated Total Reflection (FTIR-ATR) infrared spectroscopy.


Catalysts ◽  
2021 ◽  
Vol 11 (7) ◽  
pp. 756
Author(s):  
Silvija Mrkonja ◽  
Edi Topić ◽  
Mirna Mandarić ◽  
Dominique Agustin ◽  
Jana Pisk

Molybdenum compounds containing benzaldehyde-based hydrazones were obtained. The reaction in MeOH resulted with monomeric Mo complexes, [MoO2(L)(MeOH)], while the reaction in dichloromethane (DCM) provided oligomeric complexes, [MoO2(L)]n. The solid-state structures of the obtained compounds were investigated through Infrared Spectroscopy - Attenuated Total Reflection (IR-ATR), Thermogravimetric analysis (TGA), and via X-ray diffraction. The prepared molybdenum species were employed as cyclooctene epoxidation catalysts. TBHP (tert-butylhydroperoxide) in water and TBHP in decane were employed and compared as oxidants, with 0.25 mol% [Mo]. The catalyst activity and selectivity towards epoxide is >90% for all the reactions. The results have been linked to theoretical calculations, showing the importance of the first step, i.e., the transformation of [MoO2(L)(MeOH)] into the pentacoordinate [MoO2(L)].


2021 ◽  
pp. 096739112110425
Author(s):  
Volkan Ugraskan ◽  
Ebubekir Ceran ◽  
Ozlem Yazici

In the present study, it was aimed to investigate the thermoelectric (TE) properties of polyaniline/hexagonal boron nitride (PANI/h-BN) composites. First, h-BN was synthesized from boric acid and urea. Then, PANI-HCl was synthesized by oxidative chemical polymerization. Finally, the composites were prepared using different weight ratios of h-BN. The composites were characterized using attenuated total reflection accessory attached Fourier-transform infrared spectroscopy, UV-vis spectroscopy, X-ray diffraction, and scanning electron microscopy/energy dispersive X-ray analyzer. TE investigation of the composites showed that the addition of h-BN significantly contributes to the TE properties of PANI-HCl. The addition of h-BN increased the power factor of PANI-HCl from 0.07 μWm−1K−2 to 143.05 μWm−1K−2. Furthermore, all the composites showed negative Seebeck coefficients which are the characteristics of n-type semiconductors.


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