A study of bioactive glass-ceramic's mechanical properties, apatite formation, and medical applications.

Apparently, bioactive glass-ceramics are made by doing a number of steps, such as creating a microstructure from dispersed crystals within the residual glass, which provides high bending strength, and apatite crystallizes on surfaces of glass-ceramics when calcium ions are present in the blood. Apatite crystals grow on the glass and ceramic surfaces due to the hydrated silica. These materials are biocompatible with living bone in a matter of weeks, don't weaken mechanically or histologically, and exhibit good osteointegration as well as mechanical properties that are therapeutically relevant, such as fracture toughness and flexural strength.

Angiogenesis, Osseointegration, and Antibacterial Applications of Polyelectrolyte Multilayer Coatings Incorporated With Silver/Strontium Containing Mesoporous Bioactive Glass on 316L Stainless Steel.

The main causes for failure in implant surgery are prolonged exposure of implants or wound and tissue ischemia. Bacterial infection caused by the surrounding medical environment and equipment is also a major risk factor. The medical risk would be greatly reduced if we could develop an implant coating to guide tissue growth and promote antibacterial activity.

Investigation of Bone Growth in Additive-Manufactured Pedicle Screw Implant by Using Ti-6Al-4V and Bioactive Glass Powder Composite.

In this study, we optimized the geometry and composition of additive-manufactured pedicle screws. Metal powders of titanium-aluminum-vanadium (Ti-6Al-4V) were mixed with reactive glass-ceramic biomaterials of bioactive glass (BG) powders. To optimize the geometry of pedicle screws, we applied a novel numerical approach to proposing the optimal shape of the healing chamber to promote biological healing.

Deformations of Ti-6Al-4V additive-manufacturing-induced isotropic and anisotropic columnar structures: measurements and underlying mechanisms.

The deformations of isotropic and anisotropic Ti-6Al-4V columnar structures fabricated by additive manufacturing were extensively examined. The distinct texture and microstructure distributions were characterised. X-ray diffraction measurements show different lattice activities resulting from the different microstructure distributions.

Correlation of Morphology and In-Vitro Degradation Behavior of Spray Pyrolyzed Bioactive Glasses.

Bioactive glass (BG) is considered to be one of the most remarkable materials in the field of bone tissue regeneration due to its superior bioactivity. In this study, both un-treated and polyethylene glycols (PEG)-treated BG particles were prepared using a spray pyrolysis process to study the correlation between particle morphology and degradation behavior. The phase compositions, surface morphologies, inner structures, and specific surface areas of all BG specimens were examined by X-ray diffraction, scanning electron microscopy, transmission electron microscopy, and nitrogen adsorption/desorption, respectively.

Manipulation of the degradation behavior of calcium sulfate by the addition of bioglass.

A bioactive calcium sulfate/glass composite was prepared using a sintering technique, and Ca-P-Si glass particles were prepared by spray pyrolysis. The glass exhibited bioactivity in terms of its ability to form apatite in a simulated body fluid. The glass was transformed into two crystallized phases, i.

Control of Dopant Distribution in Yttrium-Doped Bioactive Glass for Selective Internal Radiotherapy Applications Using Spray Pyrolysis.

In this study, we demonstrate the fabrication of Y-doped bioactive glass (BG), which is proposed as a potential material for selective internal radiotherapy applications. Owing to its superior bioactivity and biodegradability, it overcomes the problem of yttrium aluminosilicate spheres that remain in the host body for a long duration after treatment. The preparation of Y-doped BG powders were carried out using a spray pyrolysis method.

Effect of Acetic Acid Concentration on Pore Structure for Mesoporous Bioactive Glass during Spray Pyrolysis.

Mesoporous bioactive glass (MBG) is considered as one of the most important materials in the field of bone implants and drug carriers, owing to its superior bioactivity. In previous studies, tri-block surfactants (e.g.

Composite Polyelectrolyte Multilayer and Mesoporous Bioactive Glass Nanoparticle Coating on 316L Stainless Steel for Controlled Antibiotic Release and Biocompatibility.

Bacterial infection in wounds or implants can cause osteomyelitis, eventually leading to orthopedic implant failure. In this study, polyelectrolyte multilayer (PEM) coating comprising collagen as the cationic layer, chitosan as the barrier layer and -poly-glutamic acid as the anionic layer were fabricated onto a 316L stainless steel substrate by spin coating technique. Tetracycline-loaded 57S mesoporous bioactive glass nanoparticles (57S MBG, SiO₂:CaO:P₂O = 57:33:10 by wt%) were introduced into the -poly-glutamic acid layers.

Morphology Control of Eu-Doped Amorphous Gehlenite Phosphors Prepared by Spray Pyrolysis.

Eu-doped amorphous gehlenite phosphors with various morphologies were synthesized using spray pyrolysis. Along with un-treated precursor, two commonly used pore-forming agents, polyethylene glycol and hydrogen peroxide, were applied to achieve porous and hollow particle structures. The phase compositions, surface morphologies, inner structures and photoluminescence properties of the resulting phosphors were examined by X-ray diffraction, scanning electron microscopy, transmission electron microscopy and fluorescence spectrometry.

The Correlation of Pore Size and Bioactivity of Spray-Pyrolyzed Mesoporous Bioactive Glasses.

SiO₂-CaO-P₂O₅-based mesoporous bioactive glasses (MBGs) were synthesized by spray pyrolysis in this study. Three commonly used non-ionic tri-block copolymers (L121, P123, and F127) with various lengths of hydrophilic chains were applied as structural templates to achieve different pore sizes. A mesoporous structure was observed in each as-prepared specimen, and the results showed that the L121-treated MBG had the largest pore size.

The Correlation of Surfactant Concentrations on the Properties of Mesoporous Bioactive Glass.

Bioactive glass (BG), a potential biomaterial, has received increasing attention since the discovery of its superior bioactivity. One of the main research objectives is to improve the bioactive property of BGs; therefore, surfactant-derived mesoporous bioactive glasses (MBGs) were developed to provide a high specific surface area for achieving higher bioactivity. In this study, various concentrations of typical triblock F127 surfactant were used to manipulate the morphology, specific surface area, and bioactivity of MBG particles.

Monodispersity of magnetic immuno-nanoprobes enhances the detection sensitivity of low abundance biomarkers in one drop of serum.

To enhance the detection sensitivity of target clinical protein biomarkers, a simple and rapid nanoprobe-based immuno-affinity mass spectrometry assay employing biocompatible monodisperse magnetic nanoparticles (MNPs) is reported herein. The MNPs were synthesized via a streamlined protocol that includes (a) fabrication of core MNPs using the thermal decomposition method to minimize aggregation, (b) surface protection by gold coating (MNP@Au) and surfactant coating using MNP@IGEPAL to improve hydrophilicity, and lastly, (c) oriented functionalization of antibodies to maximize immuno-affinity. The enrichment performances of the monodisperse MNPs for the C-reactive protein (CRP) serum biomarker were then evaluated and compared with aggregated magnetic nanoparticles synthesized from the conventional co-precipitation method (MNP(CP)).

The Influence of Phase Separation on Bioactivity of Spray Pyrolyzed Bioactive Glass.

In this study, bioactive glass (BG) particles were synthesized directly using spray pyrolysis (SP). Since the bioactivity of glass particles is well correlated with their chemical composition, how to obtain homogenous bioactive glass becomes an important issue. For SP, the main reason for chemical inhomogeneity was considered to be caused by the difference in the precipitation speed of each precursor.

Control of Ag nanoparticle distribution influencing bioactive and antibacterial properties of Ag-doped mesoporous bioactive glass particles prepared by spray pyrolysis.

Mesoporous bioactive glasses (MBGs) have become important bone implant materials because of their high specific surface area resulting in high bioactivity. Doping MBGs with Ag removes one of the remaining challenges to their applications, namely their lack of intrinsic antibacterial properties. In present work we demonstrate that Ag-doped MBGs can be prepared in one-step spray pyrolysis (SP) process.

Manipulation of dopant distribution in yttrium-doped ceria particles.

Yttrium is one of the most widely used dopants (e.g., in yttrium-doped ceria (YDC) and yttria-stabilized zirconia) for improving performance of solid electrolytes utilized in solid oxide fuel cells.

Characterization of mesoporosity in ceria particles using electron microscopy.

The geometry and three-dimensional (3D) morphology of the ceria particles synthesized by spray pyrolysis (SP) from two different precursors--cerium acetate hydrate and cerium nitrate hydrate (CeA and CeN ceria particles)--were characterized by transmission electron microscopy and electron tomography. Results were compared with surface area measurements, confirming that the surface area of CeA ceria particles is twice as large as that of CeN ceria particles. This result was supported by 3D microstructural observations, which have revealed that CeA ceria particles contain open pores (connected to surfaces) and closed pores (embedded in particles), while CeN ceria particles only contained closed pores.

A new system for synthesis of high quality nonpolar GaN thin films.

High quality nonpolar m-plane GaN films were successfully grown on LiGaO(2) (100) substrates for the first time. This m-plane GaN/LiGaO(2) (100) system opens a new approach for realizing highly-efficient nitride devices.

Study of nano-Ag particles doped TiO2 prepared by photocatalysis.

Nano-silver (Ag) particle doped TiO2 composite photocatalyst was prepared by photocatalytic reaction of anatase TiO2 with AgNO3 solution. Microstructures of these particles were characterized using X-ray diffraction (XRD), energy dispersive X-ray spectroscopy (EDAX) and transmission electron microscopy (TEM). Its photocatalytic behavior was examined by the degradations of two dyes, methyl orange and methylene blue.

Cross-sectional observation of yttrium and nickel oxide doped ceria powder.

In this paper, microstructures of ceria powder, synthesized using spray pyrolysis method, were characterized by focused ion beam technique and transmission electron microscopy. Dependence of the shape of powder particle on the size was found. It appears a spherical shape with the diameter less than approximately 500 nm and shows cup-like shape when their diameters become larger as a result of concaving.

The interpretation of indexing of high Sigma CSL grain boundaries from ceramics.

Electron backscatter diffraction (EBSD) is a useful technique for measuring the orientation of individual grains and for determining grain boundary misorientations in polycrystals. However, its application to ceramics is more difficult than to metals, because the surface quality that can be achieved often makes the Kikuchi patterns blurred. As a consequence, it can be difficult, even for automated systems, to differentiate between different grain orientations, which have similar patterns.

The preferred CSL misorientation distribution in polycrystalline SrTiO3.

Electron backscattered diffraction is used to investigate the preferred CSL (coincidence site lattice) distribution of polycrystalline SrTiO(3) as a function of annealing times (1 h and 16 h). Comparison of the CSL misorientations suggests that the CSL boundary energy plays a role in the preferred grain growth.