52 research outputs found
An organic-inorganic hybrid scaffold with honeycomb-like structures enabled by one-step self-assembly-driven electrospinning
Electrospun organic/inorganic hybrid scaffolds have been appealing in tissue regeneration owing to the integrated physicochemical and biological performances. However, the conventional electrospun scaffolds with non-woven structures usually failed to enable deep cell infiltration due to the densely stacked layers among the fibers. Herein, through self-assembly-driven electrospinning, a polyhydroxybutyrate/poly(e-caprolactone)/58S sol-gel bioactive glass (PHB/PCL/58S) hybrid scaffold with honeycomb-like structures was prepared by manipulating the solution composition and concentration during a one-step electrospinning process. The mechanisms enabling the formation of self-assembled honeycomb-like structures were investigated through comparative studies using Fourier-transform infrared spectroscopy (FTIR), differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA) between PHB/PCL/58S and PHB/PCL/sol-gel silica systems. The obtained honeycomb-like structure was built up from nanofibers with an average diameter of 370 nm and showed a bimodal distribution of pores: large polygonal pores up to hundreds of micrometers within the honeycomb-cells and irregular pores among the nanofibers ranging around few micrometers. The cell-materials interactions were further studied by culturing MG-63 osteoblast-like cells for 7 days. Cell viability, cell morphology and cell infiltration were comparatively investigated as well. While cells merely proliferated on the surface of non-woven structures, MG-63 cells showed extensive proliferation and deep infiltration up to 100-200 mu m into the honeycomb-like structure. Moreover, the cellular spatial organization was readily regulated by the honeycomb-like pattern as well. Overall, the newly obtained hybrid scaffold may integrate the enhanced osteogenicity originating from the bioactive components, and the improved cell-material interactions brought by the honeycomb-like structure, making the new scaffold a promising candidate for tissue regeneration.Peer reviewe
Optimization of process parameters for the synthesis of geopolymer binders
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Surface modifcation of SPIONs in PHBV microspheres for biomedical applications
Surface modification of superparamagnetic iron oxide nanoparticles (SPIONs) has been introduced with lauric acid and oleic acid via co-precipitation and thermal decomposition methods, respectively. This modification is required to increase the stability of SPIONs when incorporated in hydrophobic, biodegradable and biocompatible polymers such as poly (3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV). In this work, the solid-in-oil-in-water (S/O/W) emulsion-solvent extraction/evaporation method was utilized to fabricate magnetic polymer microspheres incorporating SPIONs in PHBV. The prepared magnetic PHBV microspheres exhibited particle sizes <1 µm. The presence of functional groups of lauric acid, oleic acid and iron oxide in the PHBV microspheres was confirmed by Fourier Transform Infrared spectroscopy (FTIR). X-ray diffraction (XRD) analysis was performed to further confirm the success of the combination of modified SPIONs and PHBV. Thermogravimetric analysis (TGA) indicated that PHBV microspheres were incorporated with SPIONsLauric as compared with SPIONsOleic. This was also proven via magnetic susceptibility measurement as a higher value of this magnetic property was detected for PHBV/SPIONsLauric microspheres. It was revealed that the magnetic PHBV microspheres were non-toxic when assessed with mouse embryotic fibroblast cells (MEF) at different concentrations of microspheres. These results confirmed that the fabricated magnetic PHBV microspheres are potential candidates for use in biomedical applications
Novel nanocomposite biomaterials with controlled copper/calcium release capability for bone tissue engineering multifunctional scaffolds
This work aimed to develop novel composite biomaterials for bone tissue engineering (BTE) made of bioactive glass nanoparticles (Nbg) and alginate cross-linked with Cu2+ or Ca2+ (AlgNbgCu, AlgNbgCa, respectively). Twodimensional scaffolds were prepared and the nanocomposite biomaterials were characterized in terms of morphology, mechanical strength, bioactivity, biodegradability, swelling capacity, release profile of the cross-linking cations and angiogenic properties. It was found that both Cu2+ and Ca2+ are released in a controlled and sustained manner with no burst release observed. Finally, in vitro results indicated that the bioactive ions released from both nanocomposite biomaterials were able to stimulate the differentiation of rat bone marrow-derived mesenchymal stem cells towards the osteogenic lineage. In addition, the typical endothelial cell property of forming tubes in Matrigel was observed for human umbilical vein endothelial cells when in contact with the novel biomaterials, particularly AlgNbgCu, which indicates their angiogenic properties. Hence, novel nanocomposite biomaterials made of Nbg and alginate cross-linked with Cu2+ or Ca2+ were developed with potential applications for preparation of multifunctional scaffolds for BTE.Fil: Cattalini, Juan Pablo. Universidad de Buenos Aires. Facultad de Farmacia y BioquĂmica. Departamento de TecnologĂa FarmacĂ©utica; ArgentinaFil: Hoppe, A.. Universitat Erlangen-Nuremberg; AlemaniaFil: Pishbin, F.. Imperial College London; Reino UnidoFil: Roether, Judith A.. Universitat Erlangen-Nuremberg; AlemaniaFil: Boccaccini, Aldo R.. Universitat Erlangen-Nuremberg; AlemaniaFil: Lucangioli, Silvia Edith. Universidad de Buenos Aires. Facultad de Farmacia y BioquĂmica. Departamento de TecnologĂa FarmacĂ©utica; Argentina. Consejo Nacional de Investigaciones CientĂficas y TĂ©cnicas; ArgentinaFil: Mouriño, Viviana Silvia Lourdes. Universidad de Buenos Aires. Facultad de Farmacia y BioquĂmica. Departamento de TecnologĂa FarmacĂ©utica; Argentina. Consejo Nacional de Investigaciones CientĂficas y TĂ©cnicas; Argentin
Copper-releasing, boron-containing bioactive glass-based scaffolds coated with alginate for bone tissue engineering
The aim of this study was to synthesize and characterize new boron-containing bioactive glass-based scaffolds coated with alginate cross-linked with copper ions. A recently developed bioactive glass powder with nominal composition (wt.%) 65 SiO2, 15 CaO, 18.4 Na2O, 0.1 MgO and 1.5 B2O3 was fabricated as porous scaffolds by the foam replica method. Scaffolds were alginate coated by dipping them in alginate solution. Scanning electron microscopy investigations indicated that the alginate effectively attached on the surface of the three-dimensional scaffolds leading to a homogeneous coating. It was confirmed that the scaffold structure remained amorphous after the sintering process and that the alginate coating improved the scaffold bioactivity and mechanical properties. Copper release studies showed that the alginate-coated scaffolds allowed controlled release of copper ions. The novel copper-releasing composite scaffolds represent promising candidates for bone regeneration.Fil: Erol, M. M.. Ä°stanbul Teknik Ăśniversitesi; TurquĂaFil: Mouriño, Viviana Silvia Lourdes. Consejo Nacional de Investigaciones CientĂficas y TĂ©cnicas; Argentina. Universidad de Buenos Aires. Facultad de Farmacia y BioquĂmica. Departamento de TecnologĂa FarmacĂ©utica; ArgentinaFil: Newby, P.. Imperial College London; Reino UnidoFil: Chatzistavrou, X.. Universitat Erlangen-Nuremberg; AlemaniaFil: Roether, Judith A.. Universitat Erlangen-Nuremberg; AlemaniaFil: Hupa, L.. Abo Akademi University; FinlandiaFil: Boccaccini, Aldo R.. Imperial College London; Reino Unido. Universitat Erlangen-Nuremberg; Alemani
Development and Characterization of Glass-Ceramics from Combinations of Slag, Fly Ash, and Glass Cullet without Adding Nucleating Agents
Developments in the field of materials science are contributing to providing solutions for the recycling of industrial residues to develop new materials. Such approaches generate new products and provide optimal alternatives to the final disposal of different types of industrial wastes. This research focused on identifying and characterizing slag, fly ash, and glass cullet from the Boyacá region in Colombia as raw materials for producing glass-ceramics, with the innovative aspect of the use of these three residues without the addition of nucleating agents to produce the glass-ceramics. To characterize the starting materials, X-ray diffraction (XRD), X-ray fluorescence (XRF), and Scanning Electron Microscopy (SEM) techniques were used. The results were used to evaluate the best conditions to produce mixtures of the three waste components and to determine the specific compositions of glass-ceramics to achieve products with attractive technical properties for potential industrial applications. The proposed mixtures were based on three compositions: Mixture 1, 2, and 3. The materials were obtained through thermal treatment at 1200 °C in a tubular furnace in accordance with the results of a comprehensive characterization using thermal analysis. The microstructure, thermal stability, and structural characteristics of the samples were examined through SEM, differential thermal analysis (DTA), and XRD analyses, which showed that the main crystalline phases were diopside and anorthite, with a small amount of enstatite and gehlenite. The obtained glass-ceramics showed properties of technical significance for structural applications
Effect of bioactive glasses on Angiogenesis: a review of in vitro and in vivo evidences
The incorporation of bioactive glass into bone tissue-engineered scaffolds can be widely beneficial based on emerging evidence in the literature about the angiogenic potential of this material, particularly 45S5 Bioglass . This article reviews the literature discussing in vitro studies which have demonstrated that increases in angiogenic indicators have been achieved through both direct and indirect contact of relevant cells with 45S5 Bioglass particles or with their dissolution products. A few available in vivo studies confirming the ability of bioactive glass, incorporated into scaffolds, to stimulate neovascularization are also discussed. Suggestions for further research are given, highlighting the need for specific investigations designed to assess the effect of particular ion dissolution products from bioactive glasses and their relative concentration on angiogenesis both in vitro and in vivo.Fil: Gorustovich Alonso, Alejandro Adrian. Comision Nacional de Energia Atomica; Argentina. Consejo Nacional de Investigaciones CientĂficas y TĂ©cnicas; ArgentinaFil: Roether, Judith A.. Imperial College London; Reino UnidoFil: Boccaccini, Aldo R.. Imperial College London; Reino Unid
Bioactive Glass Applications: A Literature Review of Human Clinical Trials
The use of bioactive glasses in dentistry, reconstructive surgery, and in the treatment of infections can be considered broadly beneficial based on the emerging literature about the potential bioactivity and biocompatibility of these materials, particularly with reference to Bioglass® 45S5, BonAlive® and 19-93B3 bioactive glasses. Several investigations have been performed (i) to obtain bioactive glasses in different forms, such as bulk materials, powders, composites, and porous scaffolds and (ii) to investigate their possible applications in the biomedical field. Although in vivo studies in animals provide us with an initial insight into the biological performance of these systems and represent an unavoidable phase to be performed before clinical trials, only clinical studies can demonstrate the behavior of these materials in the complex physiological human environment. This paper aims to carefully review the main published investigations dealing with clinical trials in order to better understand the performance of bioactive glasses, evaluate challenges, and provide an essential source of information for the tailoring of their design in future applications. Finally, the paper highlights the need for further research and for specific studies intended to assess the effect of some specific dissolution products from bioactive glasses, focusing on their osteogenic and angiogenic potential
Bioactive glasses for soft tissue engineering applications
In the last few years the usage of bioactive glasses as scaffolds for soft tissue engineering has been investigated more thoroughly. The reason for the boost in interest are the attractive properties bioactive glasses offer including bioactivity as well as antibacterial, angiogenic and hemostatic properties. So far, most research efforts have focussed on applications for repairing skin and nerve tissue although there have been interesting developments in other fields including lung and intestines, which could potentially benefit a large group of patients but more studies are required. Three comprehensive reviews on this topic have been published recently, so this chapter will mainly focus on the latest relevant published research. There are a great number of patents registered for the use of bioactive glass for hard tissue engineering, however, recently patents detailing the use of bioactive glass for soft tissue engineering applications have been filed, which open the way to market bioactive glasses for the restoration of soft tissues. The angiogenic effect of bioactive glasses is of great interest for tissue engineering applications in general and in particular for soft tissue engineering, hence the third part of this chapter will detail the latest research on the angiogenic properties of bioactive glasses.Fil: Miguez Pacheco, Valentina. Universitat Erlangen Nuremberg; AlemaniaFil: Gorustovich Alonso, Alejandro Adrian. Universidad CatĂłlica de Salta; Argentina. Consejo Nacional de Investigaciones Cientificas y Tecnicas. Oficina de Coordinacion Administrativa Houssay. Instituto de TecnologĂas y Ciencias de la Ingenieria "Hilario Fernandez Long". Grupo Vinculado al Intecin - Grupo Interdisciplinario en Materiales; ArgentinaFil: Boccaccini, Aldo Roberto. Universitat Erlangen Nuremberg; AlemaniaFil: Roether, Judith A.. Universitat Erlangen Nuremberg; Alemani
Angiogenic potential of bioactive glasses
Enhancement of the angiogenic potential of implantable tissue scaffolds is the focus of considerable research efforts in tissue engineering (TE) strategies. 1–3 Angiogenesis, the formation of new blood vessels from the endothelium of the existing vasculature, plays a pivotal role in TE and wound healing. During wound repair, microvascular endothelial cells migrate into the blood clot; they proliferate and form new blood vessels. This complex process is regulated at the molecular level by growth factors, ECM proteins, membrane receptors and signalling molecules that tightly modulate the formation of new blood vessels (Fig. 5.1).4 This process, called neovascularisation, contributes to the success of regenerating and growing new tissue, because blood vessels bring oxygen, nutrients and growth factors as well as serve as a route for inflammatory cells and precursor cells to reach to the highly metabolically active regenerating tissue. If TE scaffolds have the ability to induce neovascularisation, the viability of native or transplanted cells within scaffolds will be increased, which will enhance the possibility of engineering larger volumes of new tissues. Several approaches are being proposed to induce rapid vascular in-growth, such as gene and/or protein delivery of angiogenic growth factors and ex vivo culturing of scaffolds with endothelial cells alone or in combination with other cell types.3,5.Fil: Gorustovich Alonso, Alejandro Adrian. Consejo Nacional de Investigaciones CientĂficas y TĂ©cnicas. Centro CientĂfico TecnolĂłgico Conicet - Salta; Argentina. Universidad CatĂłlica de Salta; ArgentinaFil: Haro Durand, Luis Alberto. Consejo Nacional de Investigaciones CientĂficas y TĂ©cnicas. Centro CientĂfico TecnolĂłgico Conicet - Salta; Argentina. Universidad CatĂłlica de Salta; ArgentinaFil: Roether, Judith A.. Universitat Erlangen Nuremberg; AlemaniaFil: Boccaccini, Aldo R.. Universitat Erlangen Nuremberg; Alemani
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