Acellular Bioactivity Research Articles

Biocompatibility and antimicrobial efficacy of silver-doped borosilicate bioactive glass for tissue engineering application

Borate bioactive glasses are an auspicious material for tissue engineering applications due to their enhanced dissolution rate, bioactivity, and capacity to integrate therapeutic ions. In this study, borate-based S49B4 bioactive glass doped with silver at mass fraction of 0.5, 1, and 3 wt% were studied for bioactivity, degradation, antibacterial, and cytocompatibility. Thermogravimetric analysis revealed that the bioactive glasses were thermally stable between 600 and 700 °C. Fourier transform infrared spectroscopy and X-ray diffraction confirmed the successful synthesis of an amorphous phase of the doped borosilicate bioactive glasses and the incorporation of silver ion crystals within the structure, as well as associated contributions from borate and silicate network formers in the borosilicate bioactive glass. Morphological evaluation revealed that the borosilicate bioactive glasses exhibit a uniform and spherical shape across all formulations, with the mean particle size varying from 65 to 76 nm. An in-vitro acellular bioactivity in simulated body fluid medium showed that increasing the silver content increased the degradation rate and pH. Besides, scanning electron microscopy and Energy dispersive X-ray spectroscopy analysis revealed an upsurge in apatite production on the BBGs' surfaces as well as incremental Calcium-Phosphate ratio values of 1.50, 1.65 and 1.70 as the silver content increases. The antibacterial effect was tested against Escherichia coli and Staphylococcus aureus, while cytocompatibility was tested against human gingival epithelial cells. Silver integration at 1 wt percent yielded the most promising outcomes, which were particularly bactericidal at 79.8 % for Escherichia coli and 93.41 % for Staphylococcus aureus. Similarly, its Lactate Dehydrogenase percentage is significantly similar to the negative control employed in the study, indicating its biocompatibility. In contrast, 3 wt% silver exhibited the maximum bactericidal activity while also exhibiting mild cytotoxicity. In summary, our research indicates that elevated silver concentration enhances the bioactivity and antimicrobial characteristics of borosilicate bioactive glasses; nevertheless, a higher silver weight percent in this study also increases the possibility of cytotoxicity. It is therefore essential to carefully regulate the amount of silver doping at lower concentrations in order to maximize antibacterial action and minimize toxicity to human cells. The results presented here contribute to our understanding of the prospective use of silver doped borosilicate bioactive glasses as a possible material for tissue engineering applications.

The effect of borate on acellular bioactivity of novel mesoporous borosilicate bioactive glasses for tissue engineering

Four novel mesoporous borate-based 13–93 bioactive glass has been synthesized by a modified Stöber method. Thermogravimetric analysis, Inductively coupled plasma atomic emission spectroscopy, Fourier Transform Infrared Spectroscopy, X-Ray diffraction, Brunauer–Emmet–Teller and Barrett–Joyner–Halenda, nuclear magnetic resonance and Scanning Electron Microscope attached with Energy-dispersive X-ray spectroscopy analyses were carried out to investigate the physicochemical properties, in-vitro acellular bioactivity, and the degradation rate of the bioactive glasses in simulated body fluid across a range of times up to 21 days. The characterization data indicates that the bioactive glasses are amorphous and possess mesoporous properties. Likewise, an increase in boron content reduced the surface area and pore volume of the bioactive glass series. The observed decline is attributed to borate units' smaller atomic radius than silicate. The ability to deposit a new apatite layer in the bioactive glasses depends on the borate concentration. As such, an increase in boron content resulted in a decrease in apatite formation. Additionally, the studies showed that bioactive glasses made of borate degraded more quickly than their silicate counterpart. Overall, borate-based 13–93 bioactive glasses were effectively synthesized, and the in-vitro results showed potential usage for these bioactive glasses in tissue engineering situations where it is desirable to control bone growth or delay the onset of bioactivity.

Physical-chemical properties and acellular bioactivity of newly prepared nano-tricalcium silicate-58s bioactive glass-based endodontic sealer

ObjectivesTo evaluate the physiochemical properties and apatite-forming ability of a newly prepared nano-tricalcium silicate-58s bioactive glass-based endodontic sealer (C3S-BG-P) and compare its results with the Nishika BG canal sealer and BioRoot™ RCS. MethodsThe physicochemical properties (setting time, flow, solubility, film thickness, and radiopacity) of C3S-BG-P, Nishika BG canal sealer, and BioRoot™ RCS were evaluated in accordance with ANSI/ADA 57/2000 (reaffirmed 2012) and ISO 6876:2012 for root canal sealing materials. The in vitro apatite-forming ability was evaluated after 28 days of immersion of disc-shaped specimens in phosphate-buffered saline (PBS) using field emission scanning electron microscopy and energy-dispersive X-ray spectroscopy. ResultsThe results of physiochemical tests indicated that all the tested sealers complied with the ADA and ISO standards; however, the solubility of the BioRoot did not meet the two standards. C3S-BG-P revealed significantly superior properties in all physicochemical tests compared to Nishika and BioRoot; however, the solubility of Nishika was significantly lower than that of C3S-BG-P. Furthermore, all tested sealers exhibited apatite precipitation on their surfaces after 28 days of immersion in PBS. ConclusionsC3S-BG-P had superior physicochemical properties, which mitigated the disadvantages of calcium silicate-based sealers. Moreover, it exhibited apatite precipitation after immersion in PBS. Further in vivo studies utilizing animal models or clinical studies are necessary to support the rationale of the newly developed sealer for clinical application.

Investigation of silver-doped binary glass through modified Stöber process under surfactant

A native glass nanoparticle composition based on a binary system, “BGNPs,” was synthesized by a modified Stöber process under surfactant. Afterward, the glass was doped with silver (Ag), and their acellular bioactivity was studied. The synthesized bioactive glasses were characterized by thermogravimetric analysis (TGA), Fourier Transform Infrared Spectroscopy (FTIR), Brunauer–Emmet–Teller (BET) and Barrett–Joyner–Halenda (BJH), X-Ray diffraction (XRD), nuclear magnetic resonance (NMR) and Scanning Electron Microscope attached with Energy-dispersive X-ray spectroscopy (SEM-EDS). Further, biological properties were analyzed before and after in-vitro tests by soaking the as-prepared bioglass nanoparticles in simulated body fluid (SBF) for different periods. Apatite layers covered the surface of the prepared nanoparticles, indicating their bioactivity from SEM images. Also, the pore size distribution of nano-spheroids particle sizes was within the range of 2–5 nm, and quantitative results from the EDS confirmed the Ag-doped in BGNPs, and both SEM and XRD spectra validated the above results. Using silver-doped prepared glasses, promising results were obtained regarding apatite formation.

Cold hydrostatic sintering of 45S5 bioactive glass

Fully amorphous 45S5 bioactive glass pellets were successfully consolidated at room temperature using cold hydrostatic sintering (CHS) and their acellular bioactivity was determined by immersion test in simulated body fluid (SBF). Crystalline 45S5 BG samples prepared using conventional sintering (TS) at 1050 °C were also tested. Preliminary results indicated the formation of hydroxyapatite (HAP) on the surfaces of both samples after immersion in SBF, which was confirmed using SEM, FTIR, and XRD analyses. The amount of hydroxyapatite increases by increasing the SBF immersion time. Results revealed that the amount of HAP crystalline phase was similar in both samples after 14 days of incubation in SBF (i.e., 23% in TS and 25% in CHS samples). The pellets prepared by TS resulted in a relative density of 95.6% and a hardness of about 3.5 GPa. On the other hand, CHS samples had a hardness of 1.2 GPa and a relative density of 75.1%, indicating the presence of a porous structure that can be beneficial for the interaction of the material with proteins and cells (both in vitro and in vivo).

In vitro bioactivity and biocompatibility of magnesium implants coated with poly(methyl methacrylate) - bioactive glass composite

Magnesium (Mg) and its alloys have proved promising as biodegradable candidates for the repair of bone tissue. Despite the encouraging bio-related properties of Mg, its high corrosion rate in contact with body fluids still presents a major challenge. An efficient approach to address this issue is to provide a protective coating on Mg. The present research evaluates, for the first time, in vitro bioactivity and biocompatibility of a novel multifunctional composite coating based on poly(methyl methacrylate) (PMMA) biopolymer and bioactive glass (BG) particles on Mg-based implant. Electrophoretic deposition (EPD) was utilized to obtain this coating from a bi-component suspension. Coatings’ morphological analyses by scanning electron microscopy established that EPD provides a facile route for simultaneous deposition of the biopolymeric matrix and BG in the form of a dense and homogeneous coating on the surface of Mg. Chemical characterizations of the coatings performed by energy-dispersive spectroscopy and FT-IR spectroscopy confirmed the presence of both PMMA and BG components in the composite film. In vitro acellular bioactivity test in simulated body fluid (SBF) verified bone-like apatite formation on coatings due to the presence of BG particles. Additionally, in vitro cellular cytotoxicity using MTT assay demonstrated cellular viability in contact with the composite coatings. Moreover, the corrosion behavior of the pure Mg vs coated Mg samples in SBF was assessed electrochemically using linear polarization and impedance spectroscopy techniques. A significant increase in the polarization resistance from 65.89 Ω.cm 2 for uncoated Mg to 1365.1 Ω.cm 2 for Mg coated with a composite film (obtained from 45 g/L PMMA and 3.5 g/L BG suspension) was observed. This indicated a reduction of 95.17% in the corrosion rate of Mg substrate by application of a composite coating. The dramatic reduction in Mg substrate corrosion rate accompanied by in vitro bioactivity and cytocompatibility of the developed composite, reflect the high potential of the present strategy in the modification of Mg-based implants for successful bone tissue engineering applications. • Novel bioactive and corrosion-resistant composite coating on Mg biomedical implant • PMMA facilitates bioactive glass deposition via a facile electrophoretic method • Composite coatings were bioactive due to apatite formation in simulated body fluid • 95.17% reduction in corrosion rate in composite-coated Mg vs bare Mg • Coatings supported the growth of MG63 cells and were non-cytotoxic

Experimental borosilicate bioactive glasses: Pulp cells cytocompatibility and mechanical characterization.

To assess in vitro the effect of two novel phase separated borosilicate glasses (PSBS) in the system SiO2 -B2 O3 -K2 O-CaO-Al2 O3 on dental pulp cells; and to compare their bioactivity and mechanical properties to a conventional fluoroaluminosilicate glass ionomer cement namely FUJI IX. The cytocompatibility assessment of the two novel borosilicate glasses, one without alumina (PSBS8) and one containing alumina (PSBS16), was performed on cultured primary human pulp cells. Alamar blue assay was used to assess cell metabolic activity and cell morphology was evaluated by confocal imaging. The bioactivity in Stimulated Body Fluid was also evaluated after 1 and 3 weeks of immersion using SEM-EDX analysis. Vickers microhardness and flexural strength were assessed after incorporating the glass particles into a commercial glass ionomer cement (GIC) liquid containing both polyacrylic and polybasic carboxylic acid. The data revealed that the two borosilicate glasses enhanced cell viability ratios at all-time points in both direct and indirect contact assays. After 3 days of contact, PSBS8 without alumina showed higher viability rate (152%) compared to the PSBS16 containing alumina (145%) and the conventional glass ionomer particles (117%). EDX analysis confirmed an initial Ca/P ratio of 2.1 for 45S5K and 2.08 for PSBS8 without alumina after 3 weeks of immersion. The cement prepared using PSBS8 showed significantly higher Vickers hardness values (p=.001) than that prepared using PSBS16 (46.6 vs. 36.7 MPa). After 24 h of maturation, PSBS8 (without alumina) exhibited a flexural strength of 12.9 MPa compared to a value of 16.4 MPa for the commercial control. PSBS8 without alumina had a higher strength than PSBS16 with alumina, after 1 and 7 days of maturation (p=.001). The present in vitro results demonstrated that the borosilicate bioactive glass without alumina enhanced pulp cell viability, spreading and acellular bioactivity better than the conventional GIC and the experimental borosilicate glass containing alumina.

Copper-doped cotton-like malleable electrospun bioactive glass fibers for wound healing applications

The combination of electrospinning and sol-gel methods is attracting the interest of the scientific community for developing three-dimensional bioactive glass (BG)-based fibers. This paper reports the fabrication of cotton-like copper-doped BG fibers by combining electrospinning and sol-gel techniques. Acellular bioactivity in simulated body fluid, ion release, cell viability and scratch cell tests were performed. Results showed that copper was successfully incorporated in the fibers and Cu ions were released in limited concentration over seven days. The presence of copper delayed the mineralization of the fibers upon immersion in simulated body fluid (SBF), but it did not affect keratinocyte viability and migration. Wound closure in the scratch cell test was achieved in 48 h for all the investigated samples.

Acellular bioactivity and drug delivery of new strontium doped bioactive glasses prepared through a hydrothermal process.

This work aims to study the kinetics of apatite layer formation on the surface of strontium doped binary bioactive glasses (BG: 63S37C) prepared for the first time by a hydrothermal process and evaluate their potential for drug loading and release using ibuprofen (IBU) as an anti-inflammatory drug vector. First, the binary glass 63S37C was doped with various amounts of strontium, from 0.2 to 1 mol%. Subsequently, the amorphous state of the samples and the microstructure were assessed by TGA, XRD, FTIR, ICP-AES, and SEM-EDS. Next, the in vitro bioactivity was evaluated by following the surface morphology and composition changes of soaked samples for up to 14 days at 37 °C in simulated bodily fluid (SBF). Finally, SEM-EDS spectroscopy showed clearly the appearance of needle-shaped apatite on amorphous glass substrates at the earlier stages of immersion for bioglasses doped with strontium. These findings are also confirmed with XRD and FTIR analysis. Furthermore, 63S37C BG proved that the drug release increased with increasing strontium content. Altogether, this novel class of bioactive glasses may be considered to have a promising future for biomedical applications.

Effect of Synthesis Method of Bioactive Glasses on Acellular Bioactivity: Structural Analysis and Solid-State NMR Assessment

Effect of Synthesis Method of Bioactive Glasses on Acellular Bioactivity: Structural Analysis and Solid-State NMR Assessment

Structural characterization, in vitro bioactivity, and antibacterial evaluation of low silver-doped bioactive glasses

Four bioactive glasses (70 SiO2-(20-X) CaO-10 P2O5) containing low concentrations of silver (X Ag2O; where X = 0.5, 1, and 1.5 mol%) were synthesized by the conventional sol-gel method. Physical and structural characterization was realized using Fourier Transform Infrared (FT-IR), Thermogravimetric Analysis (TGA), X-ray Diffraction analysis (XRD), and Scanning Electron Microscopy (SEM-EDX). Acellular bioactivity tests were performed by immersion in the SBF solution. Escherichia coli and Staphylococcus aureus were used to evaluate the antibacterial activity of the prepared Ag-doped bioglasses. While FTIR, DRX, and SEM analysis displayed good acellular bioactivity for all bioactive glasses (Ag–70S), the antibacterial activity confirms well the bactericidal effect of 70S 1Ag and 70S 1.5Ag through total growth inhibition (100%) of the two pathogenic bacteria. It is also important to mention that low silver-doped bioglass nanoparticles (Ag2O ≤ 1.5 mol%) could be a required multifunctional candidate in bone tissue engineering.

A comprehensive study on copper incorporated bio-glass matrix for its potential antimicrobial applications

In this study, sol-gel derived Cu substituted 70S bioglass (70SiO2-(20-x) CaO–10P2O5-xCuO; where x = 0, 0.5, 1, 1.5) were synthesized as a new multifunctional bioactive glasses (BGs). The effect of Cu substitution in the bio-glass matrix was evaluated for its impact on pathogen (Escherichia coli and Staphylococcus aurous). Fourier Transform Infrared spectroscopy (FT-IR), Thermogravimetric Analysis (TGA), X-Ray Diffraction (XRD), Inductively Coupled Plasma spectroscopy (ICP) and Scanning Electron Microscopy (SEM) revealed that the obtained powders are amorphous silicate glass. The substituted element is present in the desired molar concentration. In vitro bioactivity test was performed in SBF solution by immersion of bioglass pellets. Antibacterial test was carried out against Escherichia coli and Staphylococcus aureus. The results showed that the prepared BGs have a high acellular bioactivity observed by a fast formation of thick and continuous layer of carbonated hydroxyapatite (CHA). The antibacterial properties of the substituted bio-glass matrix was indicated by the growth inhibition of bacterial colonies. The obtained results showed that copper substituted bio-glass is having potential to avoid post-surgical infections and it also represents the capability of hard tissue regeneration.

Tantalum doped SiO2-CaO-P2O5 based bioactive glasses: Investigation of in vitro bioactivity and antibacterial activities

AbstractMultifunctionality can be achieved for bioactive glasses by endowing them with multiple other properties along with bioactivity. One way to address this topic is by doping these glasses with therapeutic metallic ions. In this work, we put under investigation a series of bioactive glasses doped with tantalum. We aim to study the effect of tantalum, on the structure, bioactivity and antibacterial property of a ternary bioactive glass composition based on SiO2-CaO-P2O5. Fourier Transformed Infrared Spectroscopy (FTIR), X-Ray Diffraction (XRD) and Electron Scanning Microscopy (SEM) were used to assess the structural and morphological properties of these glasses and monitor their changes after in vitro acellular bioactivity test. Antibacterial activity was tested against gram positive and negative bacteria. Characterization results confirmed the presence of calcium carbonate crystallites along with the amorphous silica matrix. The assessment of bioactivity in SBF indicated that all compositions showed a fast bioactive response after only six hours of immersion period. However, analytical characterization revealed that tantalum introduced a slight latency in hydroxyapatite deposition at higher concentrations (0.8-1 %mol). Antibacterial test showed that tantalum ions had an inhibition effect on the growth of E. coli and S. aureus. This effect was more pronounced in compositions where mol% of tantalum is superior to 0.4%. These results proved that tantalum could be used, in intermediate proportions, as a promising multifunctional dopant element in bioactive glasses for bone regeneration applications.

Electrospun PCL/PGS Composite Fibers Incorporating Bioactive Glass Particles for Soft Tissue Engineering Applications.

Poly(glycerol-sebacate) (PGS) and poly(epsilon caprolactone) (PCL) have been widely investigated for biomedical applications in combination with the electrospinning process. Among others, one advantage of this blend is its suitability to be processed with benign solvents for electrospinning. In this work, the suitability of PGS/PCL polymers for the fabrication of composite fibers incorporating bioactive glass (BG) particles was investigated. Composite electrospun fibers containing silicate or borosilicate glass particles (13-93 and 13-93BS, respectively) were obtained and characterized. Neat PCL and PCL composite electrospun fibers were used as control to investigate the possible effect of the presence of PGS and the influence of the bioactive glass particles. In fact, with the addition of PGS an increase in the average fiber diameter was observed, while in all the composite fibers, the presence of BG particles induced an increase in the fiber diameter distribution, without changing significantly the average fiber diameter. Results confirmed that the blended fibers are hydrophilic, while the addition of BG particles does not affect fiber wettability. Degradation test and acellular bioactivity test highlight the release of the BG particles from all composite fibers, relevant for all applications related to therapeutic ion release, i.e., wound healing. Because of weak interface between the incorporated BG particles and the polymeric fibers, mechanical properties were not improved in the composite fibers. Promising results were obtained from preliminary biological tests for potential use of the developed mats for soft tissue engineering applications.

Investigation the in vitro biological performance of graphene/bioactive glass scaffolds using MC3T3-E1 and ATDC5 cells

ABSTRACTSilicate-based bioactive glass constructs were fabricated by polymer foam replication method for tissue engineering applications. Composites were prepared by coating the surface of bioactive glass scaffolds with poly(ε-caprolactone) involving graphene nanopowders at different concentrations. In vitro bioactivity of the composite constructs was tested in simulated body fluid. Additionally, the response of pre-osteoblastic MC3T3-E1 and chondrogenic ATDC5 cells were investigated under in vitro conditions. Results revealed that a decrease was not observed in acellular bioactivity of the scaffolds. Cell viability experiments showed that graphene involving samples were not cytotoxic to the MC3T3-E1 and ATDC5 cells (except for the samples containing 10 wt% graphene) and cells proliferated well on the scaffolds. Additionally, the pre-osteoblastic cells seeded onto the composite scaffolds differentiated into osteoblasts. The scaffolds prepared in this study may find applications for bone and cartilage tissue engineering in the presence of electric stimulation.

Preparation and characterization of PCL-coated porous hydroxyapatite scaffolds in the presence of MWCNTs and graphene for orthopedic applications

Macro-channeled porous hydroxyapatite (HA) scaffolds were fabricated by a polymer foam replication method. Composites were prepared by coating the surface of HA scaffolds with polycaprolactone (PCL) in the presence of graphene nanopowders (in the form of flakes) and multi-walled carbon nanotubes (MWCNTs) at different concentrations. Compression strength of the scaffolds was investigated as a function of additive concentration. Results revealed that the use of PCL coating increased the mechanical strength of HA scaffolds. Besides, addition of graphene or MWCNTs further improved the compression strength of the constructs when they were used at 0.25 wt% and a decrease was observed at higher graphene and MWCNT concentrations. Highest mechanical performance was obtained in composite HA scaffolds involving MWCNTs. In vitro acellular bioactivity experiments revealed that both graphene and MWCNT-incorporated HA scaffolds showed higher bioactivity in simulated body fluid compared to bare scaffolds. However, HA formation ability was more pronounced with MWCNTs compared to graphene nanoflakes where they were possibly acted as an effective nucleation sites to induce the formation of a biomimetic apatite. Additionally, scaffolds prepared in the study were found to be nontoxic to the mouse bone marrow mesenchymal stem cells.

Incorporation of Calcium Containing Mesoporous (MCM-41-Type) Particles in Electrospun PCL Fibers by Using Benign Solvents.

The electrospinning technique is a versatile method for the production of fibrous scaffolds able to resemble the morphology of the native extra cellular matrix. In the present paper, electrospinning is used to fabricate novel SiO2 particles (type MCM-41) containing poly(epsilon-caprolactone) (PCL) fibers. The main aims of the present work are both the optimization of the particle synthesis and the fabrication of composite fibers, obtained using benign solvents, suitable as drug delivery systems and scaffolds for soft tissue engineering applications. The optimized synthesis and characterization of calcium-containing MCM-41 particles are reported. Homogeneous bead-free composite electrospun mats were obtained by using acetic acid and formic acid as solvents; neat PCL electrospun mats were used as control. Initially, an optimization of the electrospinning environmental parameters, like relative humidity, was performed. The obtained composite nanofibers were characterized from the morphological, chemical and mechanical points of view, the acellular bioactivity of the composite nanofibers was also investigated. Positive results were obtained in terms of mesoporous particle incorporation in the fibers and no significant differences in terms of average fiber diameter were detected between the neat and composite electrospun fibers. Even if the Ca-containing MCM-41 particles are bioactive, this property is not preserved in the composite fibers. In fact, during the bioactivity assessment, the particles were released confirming the potential application of the composite fibers as a drug delivery system. Preliminary in vitro tests with bone marrow stromal cells were performed to investigate cell adhesion on the fabricated composite mats, the positive obtained results confirmed the suitability of the composite fibers as scaffolds for soft tissue engineering.

Highly Flexible Multifunctional Biopaper Comprising Chitosan Reinforced by Ultralong Hydroxyapatite Nanowires.

Highly flexible multifunctional biopaper comprising ultralong hydroxyapatite nanowires and chitosan (UHANWs/CS), with high weight fractions of ultralong hydroxyapatite nanowires (UHANWs) up to 100 wt. %, is reported. The as-prepared UHANWs/CS composite biopaper has high flexibility and superior mechanical properties even when the weight fraction of UHANWs is as high as 90 wt. %. In contrast, the control samples consisting of hydroxyapatite nanorods and chitosan (HANRs/CS) with weight fractions of HANRs higher than 66.7 wt.% cannot be obtained in the form of the flexible membrane. The ultimate tensile strength and Young's modulus of the UHANWs/CS composite biopaper are about 3.2 times and 4.3 times those of the HANRs/CS membrane with the same weight fraction of HAP, respectively. In addition, the UHANWs/CS composite biopaper (90 wt. % UHANWs) can be used for color printing using a commercial ink-jet printer. The surface wettability, swelling ratio, and water vapor transmission rate of the UHANWs/CS composite biopaper are adjustable by changing the addition amount of UHANWs. In vitro experiments indicate that the UHANWs/CS composite biopaper has good degradability, high acellular bioactivity and high biocompatibility. The as-prepared UHANWs/CS composite biopaper is therefore promising for various biomedical applications such as wound dressing, bone-fracture fixation, and bone-defect repair.

Acellular Bioactivity of Sol-Gel Derived Borate Glass-Polycaprolactone Electrospun Scaffolds

AbstractRecently, sol-gel derived borate glasses (BGs) have shown unprecedented conversion rates to bone-like mineral (hydroxycarbonated apatite). In an effort to explore their potential applications in bone tissue engineering, this study reports on the fabrication and characterization of BG particle incorporated electrospun "- polycaprolactone (PCL) fibrous composites. The electrospinning technique successfully incorporated PCL fibres with BG particles at 2.5 and 5 w/v%, with the higher BG loading creating a three-dimensional cotton-wool like morphology. Dynamic vapour sorption showed greater extents of mass change with BG content attributable to water sorption, and indicating greater reactivity in the composite systems. In vitro bioactivity was investigated in simulated body fluid for up to 7 days. Scanning electron microscopy, Fourier-transform infrared spectroscopy and xray diffraction indicated apatite formation in the 5 w/v% incorporated composite scaffold, which initiated as early as day 3. In summary, sol-gel derived BGs incorporatedfibrous electrospun PCL composites indicate rapid reactivity and bioactivity with potential applications in mineralized tissue engineering.

Influence of mineral phase in mineralization of a biocomposite containing chitosan, demineralized bone matrix and bone ash—in vitro study

A resorbable composite which acts as a active barrier in guided bone regeneration was fabricated using chitosan, demineralized bone matrix and bone ash. Its potential to form bone like apatite in simulated body fluid was assessed in this study. The mechanical strength of these composites was correlated with bone ash ratios and composites with better tensile strength were studied for their acellular bioactivity by incubating in simulated body fluid for 21 days. Composites without bone ash did not show acellular bioactivity which was confirmed by thermogravimetric analysis. In case of biocomposites with bone ash, there was an increase in residual weight indicating the mineralization of the composite. The composite containing bone ash has shown the peaks related to phosphate vibrations in its Fourier-transform infrared spectrum. Scanning micrographs revealed formation of apatite like crystals on its surface. Ca/P ratio was found to be 1·7 which is nearer to that of natural bone. Thus, prepared composites can be used as resorbable biocomposite in maxillofacial and oral defects.