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Brazilian Oral Research 2019This study evaluates the shear bond strength (SBS) of various resin cements to different ceramics. Composite resin cylinders of Z100 were fabricated and cemented to...
This study evaluates the shear bond strength (SBS) of various resin cements to different ceramics. Composite resin cylinders of Z100 were fabricated and cemented to disks of feldspathic ceramic (Creation), leucite-reinforced feldspathic ceramic (Empress I), and densely sintered aluminum oxide ceramic (Procera AllCeram) using five resin cements: Panavia F (PAN), RelyX ARC (ARC), RelyX Unicem (RXU), RelyX Veneer, and Variolink II. SBS was measured after three days of water storage (baseline) and after artificial aging (180 days of water storage along with 12,000 thermal cycles). Failure mode of fractured specimens also was evaluated. Data were analyzed with Kruskal-Wallis and Mann-Whitney tests (α=0.05). RXU showed 1) the lowest baseline median SBS to feldspathic ceramic, which was not statistically different from PAN; 2) the lowest median baseline SBS to leucite-reinforced feldspathic and densely sintered aluminum-oxide ceramics. All cements performed similarly after aging, except for ARC (median 0.0 MPa) and PAN (median 16.2 MPa) in the densely sintered aluminum-oxide ceramic group. Resin cements perform differently when bonded to different ceramic substrates. While all test resin cements worked similarly in the long-term to feldspathic and leucite-reinforced feldspathic ceramics, only the MDP-containing resin cement provided durable bonds to densely sintered aluminum-oxide ceramic.
Topics: Aluminum; Aluminum Silicates; Ceramics; Dental Bonding; Materials Testing; Potassium Compounds; Reference Values; Reproducibility of Results; Resin Cements; Shear Strength; Statistics, Nonparametric; Surface Properties
PubMed: 31618283
DOI: 10.1590/1807-3107bor-2019.vol33.0095 -
Molecules (Basel, Switzerland) Dec 2022GeFeO, also known as brunogeierite, is a rare mineral of germanium. It has a normal spinel structure and, as with many other spinels, amazing functional properties... (Review)
Review
GeFeO, also known as brunogeierite, is a rare mineral of germanium. It has a normal spinel structure and, as with many other spinels, amazing functional properties thanks to its peculiar structural features. In the past, its spectroscopic, optical, magnetic and electronic properties were determined; then, for many years, this compound was left behind. Only recently, a renewed interest in this oxide has arisen, particularly for its application in the electrochemical field. In this review paper, the crystal structure of GeFeO will be described, as well as the synthesis methods required to obtain single crystals or polycrystalline powders. Its spectroscopic, magnetic, optical and electrical properties will be reported in detail. Then, successful applications known so far will be described: its use as anode in Lithium Ion and Sodium Ion Batteries and as electrocatalyst for urea oxidation reaction.
Topics: Germanium; Minerals; Magnesium Oxide; Aluminum Oxide
PubMed: 36500577
DOI: 10.3390/molecules27238484 -
Environmental Toxicology Jan 2015In this study, Artemia salina (crustacean filter feeders) larvae were used as a test model to investigate the toxicity of aluminum oxide nanoparticles (Al2O3 NPs) on...
In this study, Artemia salina (crustacean filter feeders) larvae were used as a test model to investigate the toxicity of aluminum oxide nanoparticles (Al2O3 NPs) on marine microorganisms. The uptake, toxicity, and elimination of α-Al2O3 (50 nm and 3.5 μm) and γ-Al2O3 (5 nm and 0.4 μm) NPs were studied. Twenty-four and ninety-six hour exposures of different concentrations of Al2O3 NPs to Artemia larvae were conducted in a seawater medium. When suspended in water, Al2O3 NPs aggregated substantially with the sizes ranging from 6.3 nm to >0.3 µm for spherical NPs and from 250 to 756 nm for rod-shaped NPs. The phase contrast microscope images showed that NPs deposited inside the guts as aggregates. Inductively coupled plasma mass spectrometry analysis showed that large particles (3.5 μm α-Al2O3) were not taken up by Artemia, whereas fine NPs (0.4 μm γ-Al2O3) and ultra-fine NPs (5 nm γ-Al2O3 and 50 nm α-Al2O3) accumulated substantially. Differences in toxicity were detected as changing with NP size and morphology. The malondialdehyde levels indicated that smaller γ-Al2O3 (5 nm) NPs were more toxic than larger γ-Al2O3 (0.4 µm) particulates in 96 h. The highest mortality was measured as 34% in 96 h for γ-Al2O3 NPs (5 nm) at 100 mg/L (LC50 > 100 mg/L). γ-Al2O3 NPs were more toxic than α-Al2O3 NPs at all conditions.
Topics: Aluminum Oxide; Animals; Artemia; Dose-Response Relationship, Drug; Ecotoxicology; Larva; Malondialdehyde; Nanoparticles; Oxidative Stress; Particle Size; Seawater; Spectroscopy, Fourier Transform Infrared; Water Pollutants, Chemical; X-Ray Diffraction
PubMed: 24753078
DOI: 10.1002/tox.21917 -
PloS One 2023The current study describes the biogenic synthesis of two metal oxides zinc oxide (ZnO), aluminum oxide (Al2O3) nanoparticles using Camellia sinensis, and Origanum...
Biogenic synthesis of ZnO and Al2O3 nanoparticles using Camellia sinensis and Origanum vulgare L. leaves extract for spectroscopic estimation of ofloxacin and ciprofloxacin in commercial formulations.
The current study describes the biogenic synthesis of two metal oxides zinc oxide (ZnO), aluminum oxide (Al2O3) nanoparticles using Camellia sinensis, and Origanum vulgare L. leaves extract, respectively. The synthesized metal oxide nanoparticles were investigated using spectroscopic and microscopic techniques to confirm the formation of their nanostructures. Accurate and precise spectrofluorometric probes were proposed for the quantification of Ofloxacin (OFX) and Ciprofloxacin (CPFX) in their bulk and commercial formulations. The extraordinary properties of Zinc oxide and aluminum oxide nanoparticles (ZnONPs and Al2O3NPs) enhance the fluorescence intensity in the presence of 0.5 mL and 1.0 mL of sodium dodecyl sulfate (SDS, 1.0% w/v) as organizing agent for the detection of OFX and CPFX, respectively. The optical detection of both drugs at λex/em range 250-700 nm displayed linearity with a main correlation coefficient >0.999 at 1-300 (OFX-SDS-ZnONPs) and 0.5-100 (OFX-SDS-Al2O3NPs) ng mL-1,10-400 (CPFX-SDS-ZnONPs) and 0.1-50 (CPFX-SDS-Al2O3NPs) ng mL-1. The detection and quantification limits were found to be 0.04, 0.03, and 0.02, 0.04 ng mL-1, 0.13, 0.10, and 7.24, 0.09 ng mL-1 for the above-mentioned fluorescence systems, respectively. The suggested spectrofluorometric probes were validated and potentially applied for the estimation of OFX and CPFX in their bulk and commercial formulations.
Topics: Ofloxacin; Zinc Oxide; Ciprofloxacin; Camellia sinensis; Origanum; Nanoparticles; Metal Nanoparticles; Oxides; Aluminum Oxide
PubMed: 37906583
DOI: 10.1371/journal.pone.0286341 -
Molecules (Basel, Switzerland) Feb 2023The existing study pronounces two newly developed spectrofluorimetric probes for the assay of ambroxol hydrochloride in its authentic and commercial formulations using...
Comparative Study for Spectrofluorimetric Determination of Ambroxol Hydrochloride Using Aluminum Metal Transfer Chelation Complex and Biogenic Synthesis of Aluminum Oxide Nanoparticles Using Flowers Extract.
The existing study pronounces two newly developed spectrofluorimetric probes for the assay of ambroxol hydrochloride in its authentic and commercial formulations using an aluminum chelating complex and a biogenically mediated and synthesized aluminum oxide nanoparticles (AlONPs) from flower extract. The first probe is based on the formation of an aluminum charge transfer complex. However, the second probe is based on the effect of the unique optical characteristics of AlONPs in the enhancement of fluorescence detection. The biogenically synthesized AlONPs were confirmed using various spectroscopic and microscopic investigations. The fluorescence detections in the two probes were measured at a λ of 260 and 244 and a λ of 460 and 369 nm for the two suggested probes, respectively. The findings showed that the fluorescence intensity (FI) covered linear concentration ranges of 0.1-200 ng mL and 1.0-100 ng mL with a regression of ˃0.999 for AMH-AlONPs-SDS and AMH-Al(NO)-SDS, respectively. The lower detection and quantification limits were evaluated and found to be 0.04 and 0.1 ng mL and 0.7 and 0.1 ng/mL for the abovementioned fluorescence probes, respectively. The two suggested probes were successfully applied for the assay of ambroxol hydrochloride (AMH) with excellent percentage recoveries of 99.65% and 99.85%, respectively. Excipients such as glycerol and benzoic acid used as additives in pharmaceutical preparations, several common cations, and amino acids, as well as sugars, were all found to have no interference with the approach.
Topics: Ambroxol; Aluminum Oxide; Aluminum; Lavandula; Spectrometry, Fluorescence; Chelating Agents; Nanoparticles
PubMed: 36903454
DOI: 10.3390/molecules28052210 -
Acta Bio-medica : Atenei Parmensis May 2019Use of commercial products containing nanoparticles formulated from zinc oxide (ZnO) and aluminium oxide (Al2O-3) has increased significantly. These nanoparticles are... (Comparative Study)
Comparative Study
BACKGROUND AND AIM OF THE STUDY
Use of commercial products containing nanoparticles formulated from zinc oxide (ZnO) and aluminium oxide (Al2O-3) has increased significantly. These nanoparticles are widely used as ingredient in cosmetics, and also in food packaging industry although their toxicity status is yet to be studied. Here, we aimed to explore the effect of zinc oxide nanoparticles (ZnO-NPs) and aluminium oxide nanoparticles (ANPs) in human HT29 colon cancer cell line.
METHODS
In this study, ZnO-NPs were synthesized by chemical method and ANPs synthesized by sol-gel method and were characterized using UV-Vis spectroscopy, X ray diffraction and Transmittance electron microscopy. The effects of ZnO-NPs and ANPs was determined by cell viability, membrane integrity and colony formation potentials.
RESULTS
ZnO-NPs and ANPs inhibit HT29, colon cancer cell proliferation in a dose dependent manner, and affect the membrane potentials and also prevent the colony formation.
CONCLUSIONS
The results suggest that ZnO NPs are found to be more effective than ANPs in reducing colon cancer cell proliferation.
Topics: Aluminum Oxide; Cell Proliferation; Cell Survival; Colonic Neoplasms; Humans; Nanoparticles; Sensitivity and Specificity; Tumor Cells, Cultured; Zinc Oxide
PubMed: 31125002
DOI: 10.23750/abm.v90i2.6939 -
Scientific Reports May 2021Ceramic orthopaedic implants are increasingly popular due to the need for robust total joint replacement implants that have a high success rate long-term and do not...
Ceramic orthopaedic implants are increasingly popular due to the need for robust total joint replacement implants that have a high success rate long-term and do not induce biological responses in patients. This study was designed to investigate the biological effects of ceramic nanopowders containing aluminium oxide or zirconium oxide to activate the human macrophage THP-1 cell line. In vitro investigation of pro-inflammatory gene expression and chemokine secretion was performed studied using RT-qPCR and ELISA, respectively. TLR4 inhibition, using a small-molecule inhibitor, was used to determine whether ceramic-mediated inflammation occurs in a similar manner to that of metals such as cobalt. THP-1 macrophages were primed with ceramics or LPS and then treated with ATP or ceramics, respectively, to determine whether these nanopowders are involved in the priming or activation of the NLRP3 inflammasome through IL-1β secretion. Cells treated with ceramics significantly increased pro-inflammatory gene expression and protein secretion which was attenuated through TLR4 blockade. Addition of ATP to cells following ceramic treatment significantly increased IL-1β secretion. Therefore, we identify the ability of ceramic metal oxides to cause a pro-inflammatory phenotype in THP-1 macrophages and propose the mechanism by which this occurs is primarily via the TLR4 pathway which contributes to inflammasome signalling.
Topics: Aluminum Oxide; Arthroplasty, Replacement, Hip; Cell Proliferation; Cell Survival; Ceramics; Gene Expression Regulation; Humans; Inflammation; Inflammation Mediators; Macrophages; Nanoparticles; Phagocytosis; Powders; THP-1 Cells; Toll-Like Receptor 4; Zirconium
PubMed: 34006936
DOI: 10.1038/s41598-021-89329-7 -
Sensors (Basel, Switzerland) Sep 2020This review paper focuses on recent progress in optical biosensors using self-ordered nanoporous anodic alumina. We present the fabrication of self-ordered nanoporous... (Review)
Review
This review paper focuses on recent progress in optical biosensors using self-ordered nanoporous anodic alumina. We present the fabrication of self-ordered nanoporous anodic alumina, surface functionalization, and optical sensor applications. We show that self-ordered nanoporous anodic alumina has good potential for use in the fabrication of antibody-based (immunosensor), aptamer-based (aptasensor), gene-based (genosensor), peptide-based, and enzyme-based optical biosensors. The fabricated optical biosensors presented high sensitivity and selectivity. In addition, we also showed that the performance of the biosensors and the self-ordered nanoporous anodic alumina can be used for assessing biomolecules, heavy ions, and gas molecules.
Topics: Aluminum Oxide; Biosensing Techniques; Electrodes; Eye; Nanopores
PubMed: 32906635
DOI: 10.3390/s20185068 -
International Journal of Environmental... Sep 2022The high salt-alkalinity of bauxite residue (BR) hinders plant growth and revegetation of bauxite residue disposal areas (BRDA), which cause serious potential...
The high salt-alkalinity of bauxite residue (BR) hinders plant growth and revegetation of bauxite residue disposal areas (BRDA), which cause serious potential environmental and ecological risks. Bioneutralization is a promising method for improving the properties of BR and plant colonization. In the present study, a strong saline-alkali tolerant bacteria (ZH-1) was isolated from aged BR and identified as sp. The medium of ZH-1 was optimized by orthogonal tests, and ZH-1 could decrease the medium pH from 11.8 to 6.01 (agitated culture) and 6.48 (static culture) by secretion of citric acid, oxalic acid and tartaric acid. With the inoculation of ZH-1, the pH of BR decreased from 11.6 to 8.76, and the water-soluble salt in BR increased by 68.11%. ZH-1 also changed the aggregate size distribution of BR, the mechanical-stable aggregates and water-stable aggregates increased by 18.76% and 10.83%, respectively. At the same time, the stability of the aggregates obviously increased and the destruction rate decreased from 94.37% to 73.46%. In addition, the microbial biomass carbon increased from 425 to 2794 mg/kg with the inoculation of ZH-1. Bacterial community analysis revealed that Clostridia, Bacilli, Gammaproteobacteria, Betaproteobacteria and Alphaproteobacteria were the main classes in the naturalized BR, and the inoculation of ZH-1 increased the diversity of bacteria in the BR. Overall, ZH-1 has great potential for neutralization and improvement the properties of BR and may be greatly beneficial for the revegetation of BRDA.
Topics: Alkalies; Aluminum Oxide; Bacteria; Carbon; Oxalic Acid; Plants; Soil; Water
PubMed: 36141868
DOI: 10.3390/ijerph191811590 -
Molecules (Basel, Switzerland) Mar 2020This work deals with anomalous concentrations of natural mordenite in the southeast of Spain. The X-ray diffraction (XRD) and scanning electron microscopy (SEM) studies...
This work deals with anomalous concentrations of natural mordenite in the southeast of Spain. The X-ray diffraction (XRD) and scanning electron microscopy (SEM) studies evidenced that the samples contain mainly monomineral zeolitic phase of mordenite (70% to 74%), usually accompanied by smectite (montmorillonite), the principal component of bentonite. A study of the applicability of these zeolites is presented to establish the potential use as pozzolanic cements. For comparative purposes, synthetic commercial mordenite is also characterized and tested. The initial mixtures were prepared using cement and mordenite at a 75:25 ratio. Chemical analysis and a pozzolanicity test showed the high pozzolanic character. These mixtures were further added to sand and water, yielding the cement specimens to be used as concrete. Mechanical test results showed that the mechanical compression at 7 and 28 days fall into the range of 19.23 to 43.05 MegaPascals (MPa) for the cement specimens built with natural mordenites. The obtained results fall in the same range of cement specimens prepared with natural clinoptilolite, using mixtures within the European requirement for commercial concretes. Thus, these results and the low cost of natural mordenite of San José de los Escullos deposit supports the potential use of natural mordenite as pozzolanic cement.
Topics: Aluminum Silicates; Bentonite; Construction Materials; Humans; Mechanical Tests; Microscopy, Electron, Scanning; Silicates; Water; X-Ray Diffraction; Zeolites
PubMed: 32182746
DOI: 10.3390/molecules25051220