Bioglass Research Articles

Drug kinetics and antimicrobial properties of quaternary bioactive glasses 81S(81SiO2-(16-x)CaO-2P2O5-1Na2O-xMgO); an in-vitro study

Bioactive glasses have recently been attracted to meet the challenge in bone tissue regeneration, repair, healing, dental implants, etc. Among the conventional bio-glasses, a novel quaternary mesoporous nano bio-glass with composition 81S(81SiO2-(16-x)CaO-2P2O5-1Na2O-xMgO) (x = 0, 1.6, 2.4, 4 and 8 mol%) employing Stober's method has been explored for examining the above potential application through in-vitro SBF assay, MTT assay, antimicrobial activity and drug loading and release ability. With increasing the MgO concentration up to 4 mol%, from in-vitro SBF assay, we observe that HAp layer develops on the surface of the nBGs confirmed from XRD, FTIR and FESEM. MTT assay using MG-63 cells confirms the biocompatibility of the nBGs having cell viability >225 % for MGO_4 after 72 h which is more than the clinically used 45S5 bio-glass. We have observed cell viability of >125 % even after 168 h. Moreover, MGO_4 is found to restrict the growth of E. coli by 65 % while S. aureus by 75 %, confirming the antimicrobial activity. Despite an increase in the concentration of magnesium, nBGs are found to be non-toxic towards the RBCs up to 4 mol% of MgO while for 8 %, the hemolysis percentage is >6 % which is toxic. Being confirmed MGO_4 nBG as a bioactive material, various concentrations of drug (Dexamethasone (DEX)) loading and release kinetics are examined. We show that 80 % of loading in case of 10 mg-ml−1 and 70 % of cumulative release in 100 h. The mesoporous structure of MGO_4 having an average pore diameter of 5 nm and surface area of 216 m2 g−1 confirmed from BET supports the loading and release kinetics. We conclude that the quaternary MGO_4 nBG may be employed effectively for bone tissue regeneration due to its high biocompatibility, excellent in-vitro cell viability, antimicrobial response and protracted drug release.

Injectable and Microporous Microgel-Fiber Granular Hydrogel Loaded with Bioglass and siRNA for Promoting Diabetic Wound Healing.

Injectable hydrogels find extensive application in the treatment of diabetic wound healing. However, traditional bulk hydrogels are significantly limited due to their nano-porous structure, which obstructs cell migration and tissue infiltration. Moreover, regulating inflammation and matrix metalloproteinase -9 (MMP-9) expression in diabetic wounds is crucial for enhancing wound healing. This study marks the first instance of introducing an efficient, scalable, and simple method for producing microfiber-gel granules encapsulating bioceramics powders. Utilizing this method, an injectable microporous granular microgel-fiber hydrogel (MFgel) is successfully developed by assembling microgel-fibers made from hyaluronic acid (HA) and sodium alginate (SA) loaded with small interfering RNA (siRNA) and bioglass (BG) particles. Compared to traditional hydrogels (Tgel), MFgel possesses a highly interconnected network with micron-sized pores, demonstrating favorable properties for cell adhesion and penetration in in vitro experiments. Additionally, MFgel exhibits a higher compressive modulus and superior mechanical stability. When implanted subcutaneously in mice, MFgel promotes cellular and tissue infiltration, facilitating cell proliferation. Furthermore, when applied to skin defects in diabetic rats, MFgel not only effectively regulates inflammation and suppresses MMP-9 expression but also enhances angiogenesis and collagen deposition, thereby significantly accelerating diabetic wound healing. Taken together, this hydrogel possesses great potential in diabetic wound healing applications.

Bioglass 45S5, a relevant alternative to autogenous harvesting for secondary alveolar bone grafts in clefts? Retrospective study of one hundred surgeries

The secondary alveolar bone grafting (SABG) step restores the continuity of the alveolar bone necessary for dentition. Faced with the complications of autografts, synthetic biomaterials such as Bioglass (BG) 45S5 have been proposed. The objective was to evaluate the success rate of SABG with the addition of BG 45S5 and to highlight the prognostic factors.Patients who underwent operation between 2015 and 2021 and had follow-up cone-beam computed tomography (CBCT) were analyzed. Multivariate analysis was performed to determine factors influencing radiographic success. A total of 102 SABG were analyzed. They were unilateral total cleft lip and palate (49, 48.0%). The mean age at surgery was 9.32 ± 3.09 years. Surgeries were performed mainly outside a syndromic context and without a family history after orthodontic preparation.The radiographic success rate at 1 year was 80.4%. Mixed dentition stage (odds ratio [OR] = 7.3, p = 0.024), absence of syndromic context (OR = 20.7, p = 0.024) and female sex (OR = 4.88, p = 0.021) were factors predictive of surgical success.The use of BG 45S5 instead of autograft is relevant for SABG, with a 1-year success rate of over 80%. The stage of mixed dentition, the absence of syndromic context, and female sex were factors for good prognosis.

Effect of systematic substitution of Na2O for SiO2 on devitrification and bioactivity of sol-gel derived 69.5SiO2-24.5CaO-6P2O5 ceramics

Addition of Na2O to SiO2–CaO–P2O5 glass-ceramics significantly impacts in-vivo dissolution and structural network modifications. However, achieving a vitreous state in sol-gel derived quaternary oxide powders, like the 45S5 bioglass containing high amounts of Na2O, is challenging. Synthesis of (69.5-x)SiO2-24..5CaO-6P2O5-xNa2O (x = 0, 2, 4, 8, 12, 16, 20, and 24.5 wt.%) ceramic powders has been carried out followed by heat-treatment between 500 °C and 700 °C. Structural characterization revealed that the vitreous state could be stabilized for Na2O content up-to 12wt.%. For higher Na2O content, the network transformed to a glass-ceramic state with the crystallization of combeite phase. In-vitro tests exhibited hydroxyapatite layer formation (Ca/P = 1.67) on all samples in simulated body fluid, regardless of structure. Samples were non-toxic to MG-63 osteoblast cells. The devitrification, bioactivity and associate properties of the quaternary system as a function of Na2O content is discussed with respect to envisaged biomedical applications.

Glass and Glass-Ceramic Porous Materials for Biomedical Applications

Abstract Biosilicate glasses and glass-ceramic materials obtained on their basis are an important research area in tissue engineering due to their ability to regenerate bones. The most important features of bioactive glasses include: the ability to biodegrade and high bioactivity. Appropriate porosity, pore size, surface structure and topography, chemical composition and ion release kinetics, as well as mechanical properties enable the adhesion of mesenchymal cells and their differentiation towards osteoblast cells and stimulate further proliferation and angiogenesis. This study concerns the subject of bioglass, in particular Bioglass 45S5 and glass-crystalline porous materials in the context of their properties enabling the reconstruction of bone tissue and possible applications. The article addresses crucial issues of shaping the properties of glass and glasscrystalline porous structures by introducing changes in their composition and the method of their production, and also discusses the importance of foaming agents.

Green‐Prepared Magnesium Silicate Sprays Enhance the Repair of Burn‐Skin Wound and Appendages Regeneration in Rats and Minipigs

AbstractBioceramics provide promising tactics for wound healing, yet the on‐shelf products are still unmet, especially for skin appendages regeneration. Herein, the inorganic magnesium silicate sprays (MSS) as mineral factors to overcome the existing challenges is proposed. Results indicate MSS can be synthesized by a green method without organic solvents, templates, calcination, and harmful by‐products. With amorphous phase, nanoscale, and high specific surface area, MSS reveal an improved pH‐responsive degradability and excellent bioactivity for cell proliferation and migration. In rats, MSS display a dose‐dependent effect on accelerating burn‐wound repair via regulating the expressions of iNOS and IL‐10 to attenuate inflammation, elevating the expressions of CD31 and α‐SMA to improve vascularization, and boosting collagen deposition without ectopic calcification. The released Mg and Si ions synergistically potentiate the expressions of Gap43, Tubb3, and K19, suggesting the regeneration of peripheral nerves and hair follicles. These superior features are further verified by comparisons with commercial products, Dermlin® and 45S5 bioglass®, in both rats and minipigs. Motivated by these findings, three MSS‐based formulations of band‐aid patch, adhesive hydrogel, and antibacterial sprays are devised for specific scenarios. Taken together, this proof‐of concept study provides a promising bioactive mineral for future clinical skin wound repair and functional appendages regeneration.

Metformin-loaded PLGA microspheres combined with an in situ-formed injectable SA/BG hydrogel alleviate rotator cuff muscle degeneration

Rotator cuff tears are a prevalent musculoskeletal problem that affect many individuals and may result in substantial social and health-related expenses. Moreover, the muscular fat infiltration and dystrophy associated with rotator cuff tears have been persistent challenges in rotator cuff surgical repair and postoperative rehabilitation. In this study, an in situ-formed injectable sodium alginate (SA) and bioglass (BG) hydrogel consisting of poly (lactic-co-glycolic acid) (PLGA) microspheres containing metformin (SA/BG-PLGA-Met) was developed for the prevention of muscular fat infiltration and dystrophy. Metformin and silicon ions were slowly released by the combined hydrogel, resulting in long-term biological effects. Moreover, the hydrogel displayed excellent degradability and biocompatibility. Extracts of SA/BG-PLGA-Met inhibited the adipogenesis of 3T3-L1 cells and stimulated the myogenic differentiation of C2C12 cells in vitro. In a mouse model of rotator cuff degeneration, the SA/BG-PLGA-Met hydrogel inhibited fat infiltration and dystrophy of the supraspinatus muscle. Overall, the SA/BG-PLGA-Met hydrogel, as a novel biomaterial, has great clinical potential for preventing rotator cuff muscle fat infiltration and atrophy.

Thermal properties and thermodynamic model of lithium doped 45S5 bioglass

AbstractShakhmatkin and Vedishcheva thermodynamic model (SV TDM) of the 45S5 Bioglass® doped with three different amounts of Li2O (4.1, 9.9, and 12.3 mol%) was evaluated at T = 800 K. The 55 components of SV TDM were considered, among them 12 lithium containing compounds. Different number of components with not negligible equilibrium molar amount was found for different glass compositions (9 or 10). In all glass compositions containing nonzero amount of Li2O, the four lithium compounds with not negligible equilibrium amount were identified, i.e., Li2O·SiO2, 3Li2O·P2O5, Li2O·2CaO·2SiO2, and 2Li2O·SiO2. In the 45S5 glass composition four phosphate compounds with not negligible abundance were identified: 9Na2O·6SiO2·2P2O5, Na2O·2CaO·P2O5, 5Na2O·4SiO2·P2O5, and Na2O·CaO·P2O5. In all other glasses the 3Li2O.P2O5 was found with not negligible abundance. Moreover, in the glass with 4.1 mol% Li2O the Na2O·2CaO·P2O5 and 3Li2O·P2O5 compounds were found with not negligible abundance. For each studied glass the glass transition temperature, coefficient of thermal expansion of glass and metastable melt were measured by thermodilatometry. The low temperature viscosity was measured by thermomechanical analysis. The viscous flow activation energy was evaluated from the viscosity temperature dependence. The compositional dependence of measured thermal properties was analyzed by correlation analysis with the Q-distribution of silicate and phosphate units.

Gold Nanoparticle‐Coated Bioceramics for Plasmonically Enhanced Molecule Detection via Surface‐Enhanced Raman Scattering

Herein, feasibility of plasmonically enhanced molecule detection via surface‐enhanced Raman scattering for ceramics that are commonly used as bone or tooth replacement materials is evaluated. Open cell foams of Bioglass 45S5, the commercial hydroxyapatite‐based product Bio‐Oss, and bioinert zirconia‐toughened‐alumina (ZTA) are coated with Au nanoparticles via colloidal deposition to introduce plasmonic effects. Depending on the pore size, gold‐functionalized plasmonic porous Bioglass shows effective Raman enhancement factor (eEF) up to , while depositing gold nanoparticles on Bio‐Oss and porous ZTA resulted in eEF of and respectively. The performance of the plasmonic porous bioceramics under simulated biological conditions is examined in situ in the biological medium fetal bovine serum (FBS) and during extended incubation in mineralizing simulated body fluid (SBF). Most notably, the plasmonic porous Bioglass still delivered an eEF around after 28 days of incubation in SBF, indicating promising stability in simulated biological conditions without significant difference in SBF bioactivity before and after Au deposition. Accordingly, the plasmonically enhanced porous bioceramics offer the possibility for real‐time and sensitive molecule detection at SBF and FBS conditions and can be further developed for sensing of specific biomarkers, for example, in the context of osseointegration of bone replacement materials.

Dentine tubule occlusion effect of hydrolyzed casein in a bioactive glass-based dental desensitizing gel

ObjectivesThe effectiveness of three different groups of polyethylene glycol (PEG)-based gels containing powders on dentin hypersensitivity (DH) treatment were assessed and compared with Actimins® as commercial reference group. MethodsHydroxyapatite nanorods (nHA) and sol-gel-derived 45S5 bioglass (SGD 45S5) powders were synthesized through hydrothermal and sol-gel methods, respectively. First, 25 demineralized dentin disks were divided into five groups. Then, the prepared gels based on 45S5 bioglass with and without hydrolyzed casein (HC) as experimental, nHA gel and Actimins® as positive and commercial reference groups were applied twice a day on disks by a micro applicator. To mimic the oral environment, treated disks were immersed in artificial saliva in a water bath at 37 °C for 7 days. However, in the negative control group, no agent was applied on the samples. FE-SEM, EDS, AFM, and XRD were performed to assess tubule occlusion. One-way ANOVA test was used for statistical analysis and p*<0.05 was set as the significance level. ResultsThe nHA with an average aspect ratio of 2.77 and the SGD 45S5 powders with a polygonal morphology and the average size of 48.64±11.38 µm were synthesized. After treatment, tubule occlusion in HC-SGD 45S5 and nHA gels were shown to be higher than other groups. The root mean square roughness (Rrms) of the above-mentioned gels showed to be 121.54±9.25 nm, and 312.6 ± 9 nm, respectively. ConclusionThe nHA containing group exhibited the highest tubule occlusion efficiency (i.e., tubule diameter of 0.92±0.32 µm) with a superior mineral precipitation. HC as a novel material demonstrates to be potentially beneficial in DH treatment. Clinical significanceDH as a common issue may be reduced or eliminated by occlusion of patent dentinal tubules. There are various types of desensitizing agents capable of controlling the DH by the occlusion of patent dentinal tubules. The desensitizing gels developed in this study showed to be promising for clinical and home-use applications.

A study on the effect of bioactive glass and hydroxyapatite-loaded Xanthan dialdehyde-based composite coatings for potential orthopedic applications

The most important challenge faced in designing orthopedic devices is to control the leaching of ions from the substrate material, and to prevent biofilm formation. Accordingly, the surgical grade stainless steel (316L SS) was electrophoretically deposited with functional composition of biopolymers and bioceramics. The composite coating consisted of: Bioglass (BG), hydroxyapatite (HA), and lawsone, that were loaded into a polymeric matrix of Xanthan Dialdehyde/Chondroitin Sulfate (XDA/CS). The parameters and final composition for electrophoretic deposition were optimized through trial-and-error approach. The composite coating exhibited significant adhesion strength of “4B” (ASTM D3359) with the substrate, suitable wettability of contact angle 48°, and an optimum average surface roughness of 0.32 µm. Thus, promoting proliferation and attachment of bone-forming cells, transcription factors, and proteins. Fourier transformed infrared spectroscopic analysis revealed a strong polymeric network formation between XDA and CS. scanning electron microscopy and energy dispersive X-ray spectroscopy analysis displayed a homogenous surface with invariable dispersion of HA and BG particles. The adhesion, hydrant behavior, and topography of said coatings was optimal to design orthopedic implant devices. The said coatings exhibited a clear inhibition zone of 21.65 mm and 21.04 mm with no bacterial growth against Staphylococcus aureus (S. Aureus) and Escherichia coli (E. Coli) respectively, confirming the antibacterial potential. Furthermore, the crystals related to calcium (Ca) and HA were seen after 28 days of submersion in simulated body fluid. The corrosion current density, of the above-mentioned coating was minimal as compared to the bare 316L SS substrate. The results infer that XDA/CS/BG/HA/lawsone based composite coating can be a candidate to design coatings for orthopedic implant devices.

In Vitro Characterization of Doped Bioglass 45S5/HAp Coatings Obtained by CoBlastTM Deposition

Bone replacement is one of the major medical procedures in the oral surgery field due to the progressive ageing population and to illness or trauma in younger age groups. The use of implants without biological activity and effective osseointegration increases the chances of implant failure. This work aims to improve the interaction between implants and bone by using Bioglass 45S5 (BG)/hydroxyapatite (HAp) mixtures, including copper-, zinc-, and cerium-doped BG, as well as co-doping by the mentioned metals, as coatings produced by the CoBlastTM technique. All coatings present a uniform coverage of the Ti-6Al-4V substrate. Furthermore, in vitro testing using human osteosarcoma Saos-2 cells indicated that BG/HAp coatings have no cytotoxic effect, and the used of doping agents did not alter cell adhesion, proliferation, or alkaline phosphatase (ALP) expression when compared to undoped coating. These results demonstrate that BG/HAp by CoBlastTM can be a solution to improve implants’ osseointegration.

Biocomposite‐based fibrous scaffolds of natural rubber/polyhydroxybutyrate blend reinforced with 45S5 bioglass aiming at biomedical applications

AbstractThe solution blow spinning technique was used to fabricate a new biocomposite fibrous mat consisting of natural rubber (NR) and polyhydroxybutyrate (PHB) bioblend, with various loads of 45S5 bioglass (BG) particles. According to SEM analysis, NR fibers exhibited ribbon‐like morphologies, whereas the addition of PHB resulted in improved fiber formation and a reduction in their diameter. In NR‐PHB/BG biocomposites with varying BG loadings, typical thermal degradation events of PHB (stage i) and NR (stage ii) were observed. In comparison with pure PHB, the TG/DTG curves of NR‐PHB/BG specimens revealed a lower stage i degradation peak. Such an outcome is possibly due to the fact that PHB in the NR‐PHB fibers is located predominantly at the surface, that is, PHB is more susceptible to thermal degradation. The NR‐PHB/BG biocomposite possessed an increased stiffness due to the addition of PHB and BG, resulting in an increased stress and a decreased strain at rupture compared to the pure NR and NR‐PHB mats. DMA analysis revealed two well‐defined regions, above and below the glass transition temperature (Tg), for the storage modulus (E') of the NR‐PHB/BG specimens. The values of E' were in both regions for NR‐PHB/BG specimens increased at higher BG content. The measured tanδ = E″/E' was used to determine the Tg value for all specimens, with Tg found to be in the −49 to −46°C range. Finally, NR‐PHB/BG biocomposite fibrous were proven noncytotoxic by in‐vitro testing on fibroblasts. These biocomposites enhanced cell growth, holding great promise for tissue engineering applications.Highlights Solution blow spinning technique was used to produce three‐phase biocomposite specimens. NR‐PHB/BG fibrous mat specimens with a diameter of 9–10 μm were obtained. Although high BG loads are applied to the NR‐PHB/BG specimens, they remain elastic and flexible. Fibrous biocomposite mats enhance cell growth and possess great potential for tissue engineering.

Bioactive Glasses Containing Strontium or Magnesium Ions to Enhance the Biological Response in Bone Regeneration.

The non-surgical treatments are being required to reconstruct damaged tissue, prioritizing our body's natural healing process. Thus, the use of bioactive materials such as bioactive glass has been studied to support the repair and restoration of hard and soft tissue. Thus, in this work Bioglass 45S5 was developed, adding 1 and 2%mol of SrO or MgO and the physical and biological properties were evaluated. The addition of MgO and SrO at the studied concentrations promoted the slight increase in non-bridging oxygens number, observed through the temperature shift in phase transitions to lower values compared to Bioglass 45S5. The insertion of the ions also showed a positive effect on Saos-2 cell viability, decreasing the cytotoxic of Bioglass 45S5. Besides the Ca/P ratio on the pellets surface demonstrating no evidence of higher reactivity between Bioglass 45S5 and Bioglass with Sr and Mg, micrographs show that at 24 h the Ca/P rich layer is denser than in Bioglass 45S5 after the contact with simulated body fluid. The samples with Sr and Mg show a higher antibacterial effect compared to Bioglass 45S5. The addition of the studied ions may benefit the biological response of Bioglass 45S5 in dental applications as scaffolds or coatings.

Enhancing Bioactivity of Nanofibrous Poly(Caprolactone)/45S5 Bioglass Composite Scaffolds by Incorporation of Ag, GO, and ZnO Nanoparticles.

The present study endeavors toward the investigation on the bioactivity of nanofibrous scaffolds manufactured by the electrospinning process. Nanofibrous composite scaffolds of PCL with 45S5 bioactive glass and metal oxide nanoparticles were developed and characterized. The effects of incorporating silver (Ag), graphene oxide (GO), and zinc oxide (ZnO) nanoparticles into PCL/bioglass nanofibrous scaffolds on its geometry and physiochemical, morphological, mechanical, and biological properties were studied. The incorporation of GO and ZnO alters the fiber diameter, suggesting the methodology for controlling the porosity of the scaffolds. The results of FTIR and XRD confirm the structure of bioglass, Ag, GO and ZnO nanoparticles. The in vitro degradation studies in SBF solution provide evidence for the enhancement in the rate of apatite formation by the inclusion of nanoparticles as compared with PCL/BG scaffolds. The assessment of mechanical properties suggests the tensile strength was increased from 1.61 to 5 MPa in PCL/BG/ZnO system when compared with pristine PCL. The cell viability is also observed to be improved from 72% to 91% and 104% for PCL/BG/GO and PCL/BG/ZnO, respectively. The hemolytic activity studies confirm that all scaffolds are nonhemolytic in nature and PCL/BG/ZnO exhibits the least hemolytic activity of 0.65% among the other composite scaffolds, suggesting the better blood compatibility. The present study evidently shows the fact that incorporation of GO and ZnO nanoparticles with PCL in addition to BG accelerates the bioactivity and improves the mechanical strength of the scaffold.

Interfacial characteristics of bioglass diffusion zone between scaffold-like hydroxyapatite/wollastonite coating and dense zirconia substrate

A thin bioglass (BG) layer or diffusion zone has been used to enhance interfacial bonding between co-sintered scaffold-like micro-porous hydroxyapatite (HA) coating over dense zirconia substrate. However, there still have problems such as low fracture toughness and low wear resistance. Therefore, while meeting the basic requirements of degradability and biocompatibility, how to improve the mechanical properties of the scaffold, endow it with osteoinductivity and build a low-density porous structure has become the focus of bone scaffold research. The tri-layer bio-ceramic composites, consisting of porous HA, BG diffusion zone, and strong zirconia substrate, are designed with superior loading-bearing capability to the scaffold. Surface handling properties of the scaffold-like HA coating are further enhanced by incorporating wollastonite. The gradient in material compositions across the coating and substrate interface is further minimized by adding HA into the zirconia substrate. Benefiting from these special design and the thin BG diffusion zone, the tri-layer bio-ceramics present excellent interfacial strength, which ensures good structural strength and machinability. The results could provide the feasible options for bio-ceramic scaffolds design and manufacturing process, thus advance the practical clinical applications of HA-based scaffolds for bone repair and regeneration.

3D interconnected porous PMMA scaffold integrating with advanced nanostructured CaP-based biomaterials for rapid bone repair and regeneration

Bioactive scaffolds with polymer and nanostructured bioactive glass-based composites are promising materials for regenerative applications in consequence of close mimics of natural bone composition. Poly methyl methacrylate (PMMA) is a highly preferred thermoplastic polymer for orthopedic applications as it has good biocompatibility. Different kinds of bioactive, biodegradable as well as biocompatible biomaterial composites such as Bioglass (BG), Hydroxyapatite (Hap), and Tricalcium phosphate (TCP) can be integrated with PMMA, so as to augment the bioactivity, porosity as well as regeneration of hard tissues in human body. Among the bioactive glass, 60S BG (Bioactive glass with 60 percentage of Silica without Sodium ions) is better materials among aforementioned systems owning to mechanical stability as well as controlled bioactive material. In this work, the fabrication of PMMA-CaP (calcium phosphate)-based scaffolds were carried out by Thermal Induced Phase Separation method (TIPS). X-ray diffractogram analysis (XRD) is used to examine the physiochemical properties of the scaffolds that evidently reveal the presence of calcium phosphate besides calcium phosphate silicate phases. The Field Emission Scanning Electron Microscopy (FESEM) studies obviously exhibited the microstructure of the scaffolds as well as their interconnected porous morphology. The PMMA/60S BG/TCP (C50) scaffold has the maximum pore size, measuring 77 ± 23 μm, while the average pore size ranges from 50 ± 20 to 80 ± 23 μm. By performing a liquid displacement method, the C50 scaffold is found to have the largest porosity of 50%, high hydrophilicity of 118.16°, and a compression test reveals the scaffolds to have a maximum compressive strength of 0.16 MPa. The emergence of bone-like apatite on the scaffold surface after 1st and 21st days of SBF immersion is further supported by in vitro bioactivity studies. Cytocompatibility and hemocompatibility analyses undoubtedly confirmed the biocompatibility behavior of PMMA-based bioactive scaffolds. Nano-CT investigation demonstrates that PMMA-CaP scaffolds provide more or less alike morphologies of composites that resemble the natural bone. Therefore, this combination of scaffolds could be considered as potential biomaterials for bone regeneration application. This detailed study promisingly demonstrates the eminence of the unique scaffolds in the direction of regenerative medicines.

Three‐phase bio‐nanocomposite natural‐rubber‐based microfibers reinforced with cellulose nanowhiskers and 45S5 bioglass obtained by solution blow spinning

AbstractAiming at biomedical applications, the present work developed a new bio‐nanocomposite fibrous mat based on natural rubber (NR) reinforced with 45S5 bioglass particles (BG) and cellulose nanowhiskers (CNW), which reveals excellent mechanical properties, good biocompatibility and bioactivity properties. Analyses of the specimens were conducted by means of morphological observations (SEM) and thermal analysis (TG/DTG), as well as mechanical tests used to verify the effect of the incorporation of BG particles and CNW on the ultimate properties of these flexible NR‐CWN/BG fibrous membranes. An SEM analysis revealed that all filaments possessed a ribbon‐like morphology, with increasing diameters as the BG concentration increased. This likely results from an increased viscosity of the solution used for fiber blowing. In comparison with neat NR fibrous mats, the ultimate mechanical properties of bio‐nanocomposites were significantly improved due to the presence of CNW and BG particles dispersed in the NR matrix. According to the TG/DTG analysis, the specimens' thermal stability was unaffected by the high BG content, and the thermal profiles were similar, with isoprene chains decomposition of the NR occurring between 350 and 450°C. In‐vitro analysis on fibroblasts confirmed that the bio‐nanocomposite fibrous mats are noncytotoxic. It was found that fibrous mats enhanced cellular growth and hold great promise for tissue engineering applications.

Materials in the Na2O-CaO-SiO2-P2O5 System for Medical Applications.

Calcium phosphate materials and materials based on silicon dioxide have been actively studied for more than 50 years due to their high biocompatibility and bioactivity. Hydroxyapatite and tricalcium phosphate are the most known among calcium phosphate materials, and Bioglass 45S5 is the most known material in the Na2O-CaO-SiO2-P2O5 system. Each of these materials has its application limits; however, some of them can be eliminated by obtaining composites based on calcium phosphate and bioglass. In this article, we provide an overview of the role of silicon and its compounds, including Bioglass 45S5, consider calcium phosphate materials, talk about the limits of each material, demonstrate the potential of the composites based on them, and show the other ways of obtaining composite ceramics in the Na2O-CaO-SiO2-P2O5 system.

Layered PCL scaffolds modified with bioactive additives fabricated by electrospinning and 3D-printing for the nasal bone and cartilage defects

This paper presents a method for fabricating layered materials supporting the reconstruction of nasal tissues by combining the 3D/fused deposition modeling (FDM) technology with electrospinning (ES). Polycaprolactone (PCL) scaffolds modified with bioglass (BG) and zinc (Zn)-doped BG were printed from the connectable filaments sticks. Then, using the ES, a nanofibrous membrane with particles of the pharmaceutical drug Osteogenon (OST), was applied directly on a spatial scaffold. The layered scaffolds were investigated by Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), and micro-computed tomography (µCT). The bioactivity and biocompatibility of the scaffolds were evaluated by in vitro studies. The results indicated that the presence of the OST drug in the top layer of scaffolds promoted bioactivity. The presence of a membrane had a positive effect on the production and secretion of aggrecan (Agg), and incorporation of BG particles significantly improved the production and secretion of collagen type II (Col2). Each of the introduced PCL modifications leads to articular cartilage cell (NHAC-kn) viability improvement and results in a decrease in the cytotoxicity of the material. Moreover, in the long-term culture, cell proliferation was positively affected by the introduction of the OST-modified membrane and also by the addition of Zn-doped BG particles.