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To address the limitations of alginate and gelatin as separate hydrogels, partially oxidized alginate, alginate dialdehyde (ADA), is usually combined with gelatin to prepare ADA-GEL hydrogels. These hydrogels offer tunable properties, controllable degradation, and suitable stiffness for 3D bioprinting and tissue engineering applications. Several processing variables affect the final properties of the hydrogel, including degree of oxidation, gelatin content and type of crosslinking agent. In addition, in 3D-printed structures, pore size and the possible addition of a filler to make a hydrogel composite also affect the final physical and biological properties. This study utilized datasets from 13 research papers, encompassing 33 unique combinations of ADA concentration, gelatin concentration, CaCl2 and microbial transglutaminase (mTG) concentrations (as crosslinkers), pore size, bioactive glass (BG) filler content, and one identified target property of the hydrogels, stiffness, utilizing the Extreme Boost (XGB) machine learning algorithm to create a predictive model for understanding the combined influence of these parameters on hydrogel stiffness. The stiffness of ADA-GEL hydrogels is notably affected by the ADA to GEL ratio, and higher gelatin content for different ADA gel concentrations weakens the scaffold, likely due to the presence of unbound gelatin. Pore size and the inclusion of a BG particulate filler also have a significant impact on stiffness; smaller pore sizes and higher BG content lead to increased stiffness. The optimization of ADA-GEL composition and the inclusion of BG fillers are key determinants to tailor the stiffness of these 3D printed hydrogels, as found by the analysis of the available data. [ABSTRACT FROM AUTHOR]

Spinal cord injury (SCI) leads to massive cell death, disruption, and demyelination of axons, resulting in permanent motor and sensory dysfunctions. Stem cell transplantation is a promising therapy for SCI. However, owing to the poor microenvironment that develops following SCI, the bioactivities of these grafted stem cells are limited. Cell implantation combined with biomaterial therapies is widely studied for the development of tissue engineering technology. Herein, an insulin‐like growth factor‐1 (IGF‐1)‐bioactive supramolecular nanofiber hydrogel (IGF‐1 gel) is synthesized that can activate IGF‐1 downstream signaling, prevent the apoptosis of neural stem cells (NSCs), improve their proliferation, and induce their differentiation into neurons and oligodendrocytes. Moreover, implantation of NSCs carried out with IGF‐1 gels promotes neurite outgrowth and myelin sheath regeneration at lesion sites following SCI. In addition, IGF‐1 gels can enrich extracellular vesicles (EVs) derived from NSCs or from nerve cells differentiated from these NSCs via miRNAs related to axonal regeneration and remyelination, even in an inflammatory environment. These EVs are taken up by autologous endogenous NSCs and regulate their differentiation. This study provides adequate evidence that combined treatment with NSCs and IGF‐1 gels is a potential therapeutic strategy for treating SCI. [ABSTRACT FROM AUTHOR]

Bismuth being a versatile material with a wide range of therapeutic, regenerative, and antimicrobial properties lacks stability which is desired for materials to interact in a desired way with the physiological environment. Hence, synthesizing such materials requires a sensible approach because, they are sensitive to the composition of constituents, processing parameters, and the environment they are synthesized. In the current work, we introduced a novel approach to entrap bismuth in the mesoporous silica network such that the stability of the nanoparticles can be increased. The stability of the nanoparticles basically depends on the functionalization, morphology, and crystallographic arrangements of elements. This stability is expected to explore its opportunities for versatile biological applications such as bone tissue engineering and therapeutic and regenerative medicine where controlled drug release is the primary requirement. In the current work, we found the synthesized Nanoparticles were found to be stable, functional, and well-suited for possible to use in biological environments. Alongside the particle size ranging from 2 to 140 nm and exhibiting mesopore structures with uniform network connectivity is of critical interest towards biological applications. However, further biological studies are needed to confirm these findings, which will be our future work, but the current work suggests that these NPs have the potential to be a valuable new tool for bone tissue engineering that is in compliance with previous literature. [ABSTRACT FROM AUTHOR]

The balance between porosity and compressive strength, as well as the pro-osteogenic and pro-angiogenesis effects of β-tricalcium phosphate (β-TCP) are not satisfactory in the clinical application even though it has good biocompatibility, osseointegration and osteoconductivity. Herein, different contents (10, 20 and 30 wt%) of magnesium silicate (Mg 2 SiO 4, MS) and β-TCP composite bioceramic scaffolds (MS/β-TCP) were fabricated by three-dimensional fiber deposition (3DF) technology. The physicochemical, in vitro osteogenic and angiogenic properties, the early (6 weeks) cranium defect repair effects in rats and the underlying molecular mechanism on accelerating osteogenic differentiation of MS/β-TCP were systematically investigated. The results showed that MS compounding not only promoted the sintering of β-TCP and significantly enhanced the compressive strength, but also greatly improved its osteogenic and angiogenic performances, such as the viability, adhesion, and proliferation of mouse bone marrow mesenchymal stem cells (mBMSCs) and human umbilical vein endothelial cells (HUVECs), ALP activity and the expression of adhesion-related, osteogenesis-related and angiogenesis-related genes. The in vivo experiments presented that 10MS/β-TCP had more new bone formation and better angiogenesis compared to β-TCP and Blank. Analysis of the transcriptome sequencing results confirmed that the Wnt signaling pathway was involved in the regulation of osteogenic differentiation in mBMSCs by the MS/β-TCP composite bioceramic scaffold. The MS/β-TCP holds great potential in bone repair and regeneration. [ABSTRACT FROM AUTHOR]

Zirconia (ZrO 2) reinforced transparent glass ceramics (TGCs) are excellent materials for enhanced cell viability and biocompatibility for biomedical applications. Herein, ZrO 2 doped SiO 2 –Na 2 O–CaO–P 2 O 5 base compositions derived from traditional melt-quench technique. The impacts of ZrO 2 on the physical, structural, optical, morphological, and biological evaluation were studied. XRD discloses the major phase formation of buchwaldite (CaNaPO 4) and disodium calcium silicate (Na 2 CaSiO 4). Density of the TGC samples was calculated and found to be in the range of 2.535–2.910 g/cm3. The optical parameters, and particle size were estimated and analyzed. Herein, ZrO 2 plays a significant role as a network modifier and various bond assignments in the glassy network that confirmed by FTIR spectroscopy. Surface morphology and its elemental investigations were also studied using SEM and XPS techniques. Solid state NMR spectrum on 23Na, 29Si, and 31P nucleus were studied for various interactions. Moreover, the cell viability of the fabricated samples on the cancer cells were analyzed and resulted to possess the half maximum inhibitory concentrations (IC 50) of the samples were calculated and valued to be 92 to 40 μg/ml respectively. The sample 55SiO 2 –25Na 2 O–9CaO–5P 2 O 5 –6ZrO 2 (BG4) demonstrated a remarkable biological activity for bone regeneration and implants. Further, the cell cytotoxicity was evaluated by performing trypan blue assay, DAPI and DCFH-DA staining on the TGC samples. The data assembled in this research approves the hypothesis that the TGCs represent a feasible material for the biomedical applications for bone and tooth implants. [ABSTRACT FROM AUTHOR]

Zirconia based materials are widely used as dental materials because of their good mechanical properties and aesthetic, but there is a need of enhancing its biological response for clinical use. In that sense, a bioactive glass is added to zirconia matrix with the aim of improving the material biocompatibility. The effect of the raw powders synthesis method for dense zirconia/bioactive glass biomaterials was investigated. Two paths were developed to obtain zirconia-based composites with 2.5, 5 and 10 wt% addition of a bioactive glass (referred as 64S): the traditional powder mixture method, and a core-shell powder through sol-gel particle nanocoating. Particle size distribution and SEM images were performed for the powders characterization. Sol-gel coating was analyzed with TEM images and FT-IR spectra. The sintering process was studied with an optical dilatometer up to 1450 °C, and the density of the samples was calculated with the Archimedes method, in the range of 1100–1500 °C. The final crystalline phases were studied with Rietveld quantification through XRD analysis and the microstructure with SEM/EDS analysis. Vickers indentation method was used to evaluate the hardness. Biological properties were studied with murine fibroblast cell line L929 and were analyzed by fluorescence microscopy. Results showed that samples obtained by the sol-gel particle coating method enhanced the sintering process, with a sintering temperature in the range 1300–1400 °C; they showed a more homogeneous and pore-free microstructure with a higher retention of the t-ZrO 2 phase after cooling, in comparison with the samples obtained by the powder mixture method. The Vickers hardness of composites obtained by the core-shell particles had values above 11 GPa, and composites with 2.5 and 5 wt% 64S, sintered at 1400 °C, presented Vickers values of ∼13 GPa. Furthermore, biocompatibility was promoted with the addition of 64S glass, independently of the raw powders synthesis method. [Display omitted] [ABSTRACT FROM AUTHOR]

Injectable bone substitute (IBS) materials are commonly used to fill irregular-shaped bone voids in non-load-bearing areas and can offer greater utility over those which are in prefabricated powder, granule, or block forms. This work investigates the impact of liquid-to-solid ratio (LSR) on the rheology and cytocompatibility of IBSs formulated from bioactive glass particles and β-tricalcium phosphate (β-TCP) in glycerol and poly(ethylene glycol) (PEG). IBS formulations of varying LSR were prepared and packed in 3 cc open-bore syringes and sterilized via gamma irradiation (10 kGy, 25 kGy). Gamma-irradiated formulations with high PEG content required the highest (73 N) mechanical force for injection from syringes. Oscillatory viscosity measurements revealed that the viscosity of samples was directly proportional to glycerol content. PEG and glycerol displayed competing effects on the washout resistance and cohesiveness of samples, which were based on total weight loss in media and Ca2+ ion release, respectively. Cell viability in 24-h extracts of 10 kGy gamma-sterilized and 25 kGy gamma-irradiated samples were 22.94% and 56.53%, respectively. The research highlights the complex interplay of IBS components on IBS rheology and, moreover, the cytotoxicity behaviors of beta-tricalcium phosphate-based injectable bone substitutes by in vitro experiments. [ABSTRACT FROM AUTHOR]

The treatment of osteoporotic bone defect remains a big clinical challenge because osteoporosis (OP) is associated with oxidative stress and high levels of reactive oxygen species (ROS), a condition detrimental for bone formation. Anti-oxidative nanomaterials such as selenium nanoparticles (SeNPs) have positive effect on osteogenesis owing to their pleiotropic pharmacological activity which can exert anti-oxidative stress functions to prevent bone loss and facilitate bone regeneration in OP. In the current study a strategy of one-pot method by introducing Poly (lactic acid-carbonate) (PDT) and β-Tricalcium Phosphate (β-TCP) with SeNPs, is developed to prepare an injectable, anti-collapse, shape-adaptive and adhesive bone graft substitute material (PDT-TCP-SE). The PDT-TCP-SE bone graft substitute exhibits sufficient adhesion in biological microenvironments and osteoinductive activity, angiogenic effect and anti-inflammatory as well as anti-oxidative effect in vitro and in vivo. Moreover, the PDT-TCP-SE can protect BMSCs from erastin-induced ferroptosis through the Sirt1/Nrf2/GPX4 antioxidant pathway, which, in together, demonstrated the bone graft substitute material as an emerging biomaterial with potential clinical application for the future treatment of osteoporotic bone defect. Injectable, anti-collapse, adhesive, plastic and bioactive bone graft substitute was successfully synthesized. Incorporation of SeNPs with PDT into β-TCP regenerated new bone in-situ by moderating oxidative stress in osteoporotic bone defects area. The PDT-TCP-SE bone graft substitute reduced high ROS levels in osteoporotic bone defect microenvironment. The bone graft substitute could also moderate oxidative stress and inhibit ferroptosis via Sirt1/Nrf2/GPX4 pathway in vitro. Moreover, the PDT-TCP-SE bone graft substitute could alleviate the inflammatory environment and promote bone regeneration in osteoporotic bone defect in vivo. This biomaterial has the advantages of simple synthesis, biocompatibility, anti-collapse, injectable, and regulation of oxidative stress level, which has potential application value in bone tissue engineering. [Display omitted] [ABSTRACT FROM AUTHOR]

In the field of orthopedic surgery, there is an increasing need for the development of bone replacement materials for the treatment of bone defects. One of the main focuses of biomaterials engineering are advanced bioceramics like mesoporous bioactive glasses (MBG´s). The present study compared the new bone formation after 12 weeks of implantation of MBG scaffolds with composition 82,5SiO 2 –10CaO–5P 2 O 5 -x 2.5SrO alone (MBGA), enriched with osteostatin, an osteoinductive peptide, (MBGO) or enriched with bone marrow aspirate (MBGB) in a long bone critical defect in radius bone of adult New Zealand rabbits. New bone formation from the MBG scaffold groups was compared to the gold standard defect filled with iliac crest autograft and to the unfilled defect. Radiographic follow-up was performed at 2, 6, and 12 weeks, and microCT and histologic examination were performed at 12 weeks. X-Ray study showed the highest bone formation scores in the group with the defect filled with autograft, followed by the MBGB group, in addition, the microCT study showed that bone within defect scores (BV/TV) were higher in the MBGO group. This difference could be explained by the higher density of newly formed bone in the osteostatin enriched MBG scaffold group. Therefore, MBG scaffold alone and enriched with osteostatin or bone marrow aspirate increase bone formation compared to defect unfilled, being higher in the osteostatin group. The present results showed the potential to treat critical bone defects by combining MBGs with osteogenic peptides such as osteostatin, with good prospects for translation into clinical practice. Treatment of bone defects without the capacity for self-repair is a global problem in the field of Orthopedic Surgery, as evidenced by the fact that in the U.S alone it affects approximately 100,000 patients per year. The gold standard of treatment in these cases is the autograft, but its use has limitations both in the amount of graft to be obtained and in the morbidity produced in the donor site. In the field of materials engineering, there is a growing interest in the development of a bone substitute equivalent. Mesoporous bioactive glass (MBG´s) scaffolds with three-dimensional architecture have shown great potential for use as a bone substitutes. The osteostatin-enriched Sr-MBG used in this long bone defect in rabbit radius bone in vivo study showed an increase in bone formation close to autograft, which makes us think that it may be an option to consider as bone substitute. [Display omitted] [ABSTRACT FROM AUTHOR]

Silicate and borate bioactive glasses have been reported to create alkaline conditions by rapidly releasing ions when reacting in aqueous solution. At certain levels, this alkaline solution can negatively affect cell viability. Adding phosphate ions to the glass composition can control the degradation rate of bioactive glasses and create a neutral pH environment. This study evaluated a series of borophosphate bioactive glasses (BPBGs) with nominal molar compositions 16Na2O-24CaO-xB2O3-(60-x)P2O5, where x = 0, 40, or 60. The phosphate (X0) glass (PBG) produced an acidic solution when dissolved in water; the borate (X60) glass (BBG) produced an alkaline solution, and the BPBG glass produced a pH-neutral solution. These three glasses were evaluated using adipose stem cells (ASCs), a cell population known for their therapeutic abilities. The effects of each glass on the pH of cell culture, ions released during degradation, and on ASC functions, including viability, migration, angiogenic ability, differentiation, and protein secretions, were evaluated. The X40 BPBG created a physiologically neutral pH in cell culture media after 24 h. The X0 phosphate glass promoted ASC migration, while the highly alkaline X60 borate increased the angiogenic ability of ASCs. These results indicate that BPBG can be used safely in cell culture studies and customized for specific biomedical applications. [ABSTRACT FROM AUTHOR]

The field of tissue engineering has witnessed significant advancements in recent years, driven by the pursuit of innovative solutions to address the challenges of bone regeneration. In this study, we developed an electrospun composite scaffold for bone tissue engineering. The composite scaffold is made of a blend of poly(L‐lactide‐co‐ε‐caprolactone) (PLCL) and polyethylene glycol (PEG), with the incorporation of calcined and lyophilized silicate‐chlorinated bioactive glass (BG) particles. Our investigation involved a comprehensive characterization of the scaffold's physical, chemical, and mechanical properties, alongside an evaluation of its biological efficacy employing alveolar bone‐derived mesenchymal stem cells. The incorporation of PEG and BG resulted in elevated swelling ratios, consequently enhancing hydrophilicity. Thermal gravimetric analysis confirmed the efficient incorporation of BG, with the scaffolds demonstrating thermal stability up to 250°C. Mechanical testing revealed enhanced tensile strength and Young's modulus in the presence of BG; however, the elongation at break decreased. Cell viability assays demonstrated improved cytocompatibility, especially in the PLCL/PEG+BG group. Alizarin red staining indicated enhanced osteoinductive potential, and fluorescence analysis confirmed increased cell adhesion in the PLCL/PEG+BG group. Our findings suggest that the PLCL/PEG/BG composite scaffold holds promise as an advanced biomaterial for bone tissue engineering. [ABSTRACT FROM AUTHOR]

Bioglass 45S5, a silica-based glass, has pioneered a new field of biomaterials. Bioglass 45S5 promotes mineralization through calcium ion release and is widely used in the dental field, including toothpaste formulations. However, the use of Bioglass 45S5 for bone grafting is limited owing to the induction of inflammation, as well as reduced degradation and ion release. Phosphate-based glasses exhibit higher solubility and ion release than silica-based glass. Given that these glasses can be synthesized at low temperatures (approximately 1,000°C), they can easily be doped with various metal oxides to confer therapeutic properties. Herein, we fabricated zinc- and fluoride-doped phosphate-based glass (multicomponent phosphate [MP] bioactive glass) and further doped aluminum oxide into the MP glass (4% Al-MP glass) to overcome the striking solubility of phosphate-based glass. Increased amounts of zinc and fluoride ions were detected in water containing the MP glass. Doping of aluminum oxide into the MP glass suppressed the striking dissolution in water, with 4% Al-MP glass exhibiting the highest stability in water. Compared with Bioglass 45S5, 4% Al-MP glass in water had a notably reduced particle size, supporting the abundant ion release of 4% Al-MP glass. Compared with Bioglass 45S5, 4% Al-MP glass enhanced the osteogenesis of mouse bone marrow–derived mesenchymal stem cells. Mouse macrophages cultured with 4% Al-MP glass displayed enhanced induction of anti-inflammatory M2 macrophages and reduced proinflammatory M1 macrophages, indicating M2 polarization. Upon implanting 4% Al-MP glass or Bioglass 45S5 in a mouse calvarial defect, 4% Al-MP glass promoted significant bone regeneration when compared with Bioglass 45S5. Hence, we successfully fabricated zinc- and fluoride-releasing bioactive glasses with improved osteogenic and anti-inflammatory properties, which could serve as a promising biomaterial for bone regeneration. [ABSTRACT FROM AUTHOR]

In this study, strontium‐doped mesoporous bioactive glass nanoparticles (Sr‐MBGNs) were incorporated into a poly(xylitol‐citrate‐sebacate) (PXCS) matrix using solution mixing techniques. The resulting composites, including PXCS, PXCS/1.5% Sr‐MBGNs, PXCS/3% Sr‐MBGNs, and PXCS/5% Sr‐MBGNs, were characterized for biomedical applications using FTIR, DSC, and x‐ray diffraction analyses. High‐resolution scanning electron microscopy (HRSEM) and a universal testing machine were employed to investigate the structure, morphology, and mechanical properties of the polymer and its nanocomposites. Our findings indicate that the introduction of polymer and its nanocomposites minimally affects the glass transition and crystallinity. The observed decrease in glass transition temperature with increasing Sr‐MBGNs content suggests a plasticizing effect. These results are consistent with previous studies. Additionally, in vitro studies were conducted to evaluate antibacterial properties, VERO cell line proliferation, degradation, and swelling percentage of the scaffolds. Metal ions release behavior was assessed using inductively coupled plasma atomic emission spectrometry (ICP‐AES) Furthermore, the drug loading and release of curcumin from PXCS/5% Sr‐MBGNs and PXCS/Sr‐MBGNs nanocomposite scaffolds were investigated at varying pH levels (pH: 5.5, 6.8, and 7.4). Both PXCS/5% Sr‐MBGNs and PXCS/5% Sr‐MBGNs scaffolds demonstrated enhanced biological properties, highlighting their potential for use in bone regeneration approaches. [ABSTRACT FROM AUTHOR]

Bioactive glasses have been shown effective in promoting bone healing by interacting with the body, gradual degradation, and supporting new bone growth. They present a promising option for therapies aimed at regenerating bone tissue. In this study, we developed a novel material, PXMA/n‐BG, by combining xylitol, maleic acid, and adipic acid, and incorporating nano‐bioactive glass, all synthesized without the use of a catalyst. The sol–gel method was used to fabricate the n‐BG (SiO2–CaO–P2O5). The incorporation of n‐BG into the polymer was found to enhance its biocompatibility and effectiveness for orthopedic applications. The synthesized polymer and its nanocomposite were characterized by FTIR, 1H NMR, 13C NMR, DSC, GPC, UTM, XRD and HR‐SEM. X‐ray diffraction and high‐resolution scanning electron microscopy are utilized to investigate the structure and surface of the n‐BG and polymeric composite material. The strength and flexibility of a plastic material with tiny particles mixed in were tested using a universal testing machine. We examined the elemental composition and thermal stability of n‐BG through specialized testing like energy‐dispersive X‐ray analysis (EDX) and thermogravimetric analysis (TGA). The research focused on the potential of xylitol‐based polymer and its nanocomposite to inhibit the growth of harmful bacteria in food. We conducted experiments to determine the efficacy of the antibacterial substance against various bacteria strains. The antibacterial potential of the extracts was assessed by the agar diffusion method using MHA plate. Furthermore, we investigated the ability of the material and its nanoparticles to reduce inflammation. [ABSTRACT FROM AUTHOR]

This study aims to develop multi-functional bio-safe dental resin composites with capabilities for mineralization, high in vitro biocompatibility, and anti-biofilm properties. To address this issue, experimental resin composites consisting of UDMA/TEGDMA-based dental resins and low quantities (1.9, 3.8, and 7.7 vol%) of 45S5 bioactive glass (BAG) particles were developed. To evaluate cellular responses of resin composites, MC3T3-E1 cells were (1) exposed to the original composites extracts, (2) cultured directly on the freshly cured resin composites, or (3) cultured on preconditioned composites that have been soaked in deionized water (DI water), a cell culture medium (MEM), or a simple HEPES-containing artificial remineralization promotion (SHARP) solution for 14 days. Cell adhesion, cell viability, and cell differentiation were, respectively, assessed. In addition, the anti-biofilm properties of BAG-loaded resin composites regarding bacterial viability, biofilm thickness, and biofilm morphology, were assessed for the first time. In vitro biological results demonstrated that cell metabolic activity and ALP expression were significantly diminished when subjected to composite extracts or direct contact with the resin composites containing BAG fillers. However, after the preconditioning treatments in MEM and SHARP solutions, the biomimetic calcium phosphate minerals on 7.7 vol% BAG-loaded composites revealed unimpaired or even better cellular processes, including cell adhesion, cell proliferation, and early cell differentiation. Furthermore, resin composites with 1.9, 3.8, and 7.7 vol% BAG could not only reduce cell viability in S. mutans biofilm on the composite surface but also reduce the biofilm thickness and bacterial aggregations. This phenomenon was more evident in BAG7.7 due to the high ionic osmotic pressure and alkaline microenvironment caused by BAG dissolution. This study concludes that multi-functional bio-safe resin composites with mineralization and anti-biofilm properties can be achieved by adding low quantities of BAG into the resin system, which offers promising abilities to mineralize as well as prevent caries without sacrificing biological activity. [ABSTRACT FROM AUTHOR]

Objective: Dental hypersensitivity remains widespread, underscoring the need for materials that can effectively seal dental tubules. This study evaluated the potential of bioactive-glass-infused hydroxyethyl cellulose gels in this context. Methods: Five gels were synthesized, each containing 20% bioactive glass (specifically, 45S5, S53P4, Biomin F, and Biomin C), with an additional blank gel serving as a control. Subjected to two months of accelerated aging at 37 ± 2 °C, these gels were assessed for key properties: viscosity, water disintegration time, pH level, consistency, adhesion to glass, and element release capability. Results: Across the board, the gels facilitated the release of calcium, phosphate, and silicon ions, raising the pH from 9.00 ± 0.10 to 9.7 ± 0.0—a range conducive to remineralization. Dissolution in water occurred within 30–50 min post-application. Viscosity readings showed variability, with 45S5 reaching 6337 ± 24 mPa/s and Biomin F at 3269 ± 18 mPa/s after two months. Initial adhesion for the blank gel was measured at 0.27 ± 0.04 Pa, increasing to 0.73 ± 0.06 Pa for the others over time. Gels can release elements upon contact with water (Ca− Biomin C 104.8 ± 15.7 mg/L; Na− Biomin F 76.30 ± 11.44 mg/L; P− Biomin C 2.623 ± 0.393 mg/L; Si− 45S5-45.15 ± 6.77mg/L, F− Biomin F− 3.256 ± 0.651mg/L; Cl− Biomin C 135.5 ± 20.3 mg/L after 45 min). Conclusions: These findings highlight the gels' capacity to kickstart the remineralization process by delivering critical ions needed for enamel layer reconstruction. Further exploration in more dynamic, real-world conditions is recommended to fully ascertain their practical utility. [ABSTRACT FROM AUTHOR]

Aim: To evaluate the efficacy of incorporated novel additives in Glass Ionomer Cement to ameliorate biocompatibility and mechanical properties. Introduction: Though Glass Ionomer Cement (GIC) has multiple advantages, it is not strong enough for medical applications, and its biocompatibility is questionable. To improve biocompatibility and its mechanical properties, a study was performed to investigate the potential benefits of adding graphene, carbon nanotubes, hydroxyapatite, and bioactive glass to GIC. The objective was to enhance both the mechanical properties and biocompatibility of GIC. Material and Method: Modified Glass Ionomer Cement was prepared by creating five groups. Hydroxyapatite, multi-walled carbon nanotubes, graphene, and bioactive glass were incorporated in a 10:1 weight ratio, respectively. Group 5 was designated as the control group and used Fuji Type II GIC. After preparing 90 samples, they were kept in deionized water for a day and then evaluated their compressive strength, microhardness, and diametral tensile strength, and also checked their in vitro cytotoxicity by direct contact with L929 mammalian fibroblast cells. Statistical Analysis: The data were examined using mean and standard deviation descriptive statistics. The comparative evaluation was done via Tukey HSD test and one-way ANOVA using S.P.S.S. software. Result: It showed that Group 3 had better results in compressive strength (144.478+- 3.989), diametral tensile strength (20.29+- 0.8601), and microhardness (131+-3.536) when compared with other groups while in the biocompatibility (viability %) Group 1 [82.55], Group 3 [76.49], Group 4 [87.63], while Group 2[58.02]. Conclusion: Group 3 has better physical properties in microhardness, diametral tensile strength, and compressive strength, than the other groups. In Biocompatibility, Group 1, Group 3, Group 4, and Group 5 were noncytotoxic at the same time multi-walled carbon nanotubes group (Group 2) had cytotoxic potential. [ABSTRACT FROM AUTHOR]

This study aims to develop a mesoporous forsterite spheres-based scaffold for bone tissue regeneration. To achieve this goal, mesoporous forsterite spheres were fabricated using alginate (gel-forming agent) and activated charcoal (porogen). The impact of carbon concentration (2, 5, 10, and 20 wt %) and sintering temperature (1100 and 1200 °C) on the structural properties of mesoporous forsterite spheres was investigated. Additionally, gelatin coatings were applied to modify these spheres. Forsterite microspheres with a particle size of 2.43 ± 0.22 mm were successfully produced, exhibiting varying pore sizes based on the sintering temperature and carbon content. Notably, mesoporous forsterite spheres synthesized using 5 wt% carbon and sintered at 1200 °C displayed uniform morphology, a minor average diameter (2.4 ± 0.3 mm(, and an average pore size of 2.7 ± 0.9 μm. These optimized forsterite spheres exhibited mesoporous structures with superior surface area (2.93 m2g-1) and pore volume (0.009–0.048 cm3g-1). Furthermore, the gelatin coating, with an average thickness of 160 μm, was effectively applied to the forsterite spheres. The gelatin coating reduced the surface area (1.40 m2g-1), pore volume (0.003 cm3g-1), and average pore diameter to 9.26 nm, maintaining the mesoporous structure. Both mesoporous forsterite spheres successfully induced bone-like apatite formation in vitro during a 21-day immersion in simulated body fluid. Moreover, while both forsterite-based spheres exhibited cytocompatibility with MG63 cells (cell viability >80 %), the gelatin coating significantly enhanced osteogenic differentiation (1.29 times). In conclusion, gelatin-coated mesoporous forsterite spheres exhibit promising potential as bioactive filling scaffolds for bone tissue regeneration. [ABSTRACT FROM AUTHOR]

In this work, the ion-exchange technique in molten salts was investigated to introduce copper ions in a bioactive and ferrimagnetic devitrified glass. This approach aimed to develop a magnetic and bioactive material for oncologic bone implants, able to join the ability to promote bone bonding to hyperthermic therapy while simultaneously lowering the risk of developing post-surgery infections. The ion-exchange approach was developed in order to overcome experimental critical issues related to the influence of copper introduction as a starting reagent, during the material synthesis, on magnetite nucleation. The magnetic devitrified glass was prepared by melt and quenching route, followed by ion exchange in a mixture of molten sodium and copper nitrates, in three different Na/Cu molar ratios (20, 200, 2000). The obtained samples were analysed in terms of morphology, composition, ability to release heat, bioactivity and antibacterial properties. The results revealed that copper ion-exchange involved both sodium and calcium ions and the precipitation of few amounts of copper oxide aggregates occurred. The crystalline nature of the starting material and its ability to reach the temperature needed for hyperthermia, under exposition to an alternating magnetic field, were not affected. A bacteriostatic effect was obtained by samples with the highest copper amount and the copper doping did not affect the bioactivity of the glass ceramic. [ABSTRACT FROM AUTHOR]

This study investigates the profound impact of the ZrO2 inclusion volume on the characteristics of Al2O3/ZrO2 nanocomposites, particularly influencing the formation of calcium phosphates on the surface. This research, aimed at advancing tissue engineering, prepared nanocomposites with 5, 10, and 15 vol% ZrO2, subjecting them to chemical surface treatment for enhanced calcium phosphate deposition sites. Biomimetic coating with Sr-enriched simulated body fluid (SBF) further enhanced the bioactivity of nanocomposites. While the ZrO2 concentration heightened the oxygen availability on nanocomposite surfaces, the quantity of Sr-containing phosphate was comparatively less influenced than the formation of calcium phosphate phases. Notably, the coated nanocomposites exhibited a high cell viability and no toxicity, signifying their potential in bone tissue engineering. Overall, these findings contribute to the development of regenerative biomaterials, holding promise for enhancing bone regeneration therapies. [ABSTRACT FROM AUTHOR]

Biomaterials are extensively used as replacements for damaged tissue with bioactive glasses standing out as bone substitutes for their intrinsic osteogenic properties. However, biomaterial implantation has the following risks: the development of implant-associated infections and adverse immune responses. Thus, incorporating metallic ions with known antimicrobial properties can prevent infection, but should also modulate the immune response. Therefore, we selected silver, copper and tellurium as doping for bioactive glasses and evaluated the immunophenotype and cytokine profile of human T-cells cultured on top of these discs. Results showed that silver significantly decreased cell viability, copper increased the T helper (Th)-1 cell percentage while decreasing that of Th17, while tellurium did not affect either cell viability or immune response, as evaluated via multiparametric flow cytometry. Multiplex cytokines assay showed that IL-5 levels were decreased in the copper-doped discs, compared with its undoped control, while IL-10 tended to be lower in the doped glass, compared with the control (plastic) while undoped condition showed lower expression of IL-13 and increased MCP-1 and MIP-1β secretion. Overall, we hypothesized that the Th1/Th17 shift, and specific cytokine expression indicated that T-cells might cross-activate other cell types, potentially macrophages and eosinophils, in response to the scaffolds. [ABSTRACT FROM AUTHOR]

Immune response to biomaterials, which is intimately related to their surface properties, can produce chronic inflammation and fibrosis, leading to implant failure. This study investigated the development of magnetic nanoparticles coated with silica and incorporating the anti-inflammatory drug naproxen, aimed at multifunctional biomedical applications. The synthesized nanoparticles were characterized using various techniques that confirmed the presence of magnetite and the formation of a silica-rich bioactive glass (BG) layer. In vitro studies demonstrated that the nanoparticles exhibited bioactive properties, forming an apatite surface layer when immersed in simulated body fluid, and biocompatibility with bone cells, with good viability and alkaline phosphatase activity. Naproxen, either free or encapsulated, reduced nitric oxide production, an inflammatory marker, while the BG coating alone did not show anti-inflammatory effects in this study. Overall, the magnetic nanoparticles coated with BG and naproxen showed promise for biomedical applications, especially anti-inflammatory activity in macrophages and in the bone field, due to their biocompatibility, bioactivity, and osteogenic potential. [ABSTRACT FROM AUTHOR]

In this paper, the in vivo behavior of orthopedic implants covered with thin films obtained by matrix-assisted pulsed laser evaporation and containing bioactive glass, a polymer, and natural plant extract was evaluated. In vivo testing was performed by carrying out a study on guinea pigs who had coated metallic screws inserted in them and also controls, following the regulations of European laws regarding the use of animals in scientific studies. After 26 weeks from implantation, the guinea pigs were subjected to X-ray analyses to observe the evolution of osteointegration over time; the guinea pigs' blood was collected for the detection of enzymatic activity and to measure values for urea, creatinine, blood glucose, alkaline phosphatase, pancreatic amylase, total protein, and glutamate pyruvate transaminase to see the extent to which the body was affected by the introduction of the implant. Moreover, a histopathological assessment of the following vital organs was carried out: heart, brain, liver, and spleen. We also assessed implanted bone with adjacent tissue. Our studies did not find significant variations in biochemical and histological results compared to the control group or significant adverse effects caused by the implant coating in terms of tissue compatibility, inflammatory reactions, and systemic effects. [ABSTRACT FROM AUTHOR]

BACKGROUND: The remediation and treatment of bone defects present considerable challenges, with a variety of clinical intervention strategies available. One such approach, the Masquelet technique, has demonstrated high rates of success and reliable outcomes and is currently employed in clinical practice. However, the underlying mechanisms of this technique remain incompletely understood, and certain challenges persist in its clinical application, indicating that this technique is not yet fully mature. OBJECTIVE: To compile and categorize the biomaterials currently employed in research aimed at improving the Masquelet technique, in order to provide insights and references for the further development of this technique. METHODS: A literature search of the China National Knowledge Infrastructure and PubMed databases was conducted, spanning publications from January 2013 to November 2022. The search terms used included “Masquelet technique; induced membrane technique; induced membrane; biomaterial; bone defect” in both Chinese and English. A total of 58 articles meeting the inclusion criteria were reviewed. RESULTS AND CONCLUSION: (1) The emergence and continual development of the Masquelet technique provide a therapeutic strategy for treating bone defects. Some researchers are focusing on developing superior spacer materials, autograft substitutes, and membrane materials that mimic the properties of the induced membrane, to simplify the two-stage procedure, shorten treatment duration, and reduce patient distress. (2) Calcium sulfate, silicone, poly(lactic-co-glycolic acid), and polypropylene can replace polymethylmethacrylate bone cement to form induced membranes in animal experiments or clinical applications, each with their advantages. Contrary to expectations, common materials such as titanium and polyvinyl alcohol sponge cannot replace polymethylmethacrylate bone cement. (3) Autograft substitutes are diverse, with allograft bone, β-tricalcium phosphate, absorbable gelatin sponge, α-calcium sulfate hemihydrate, bioactive glass, titanium, and tantalum demonstrating their ability to reduce the quantity of autologous cancellous bone graft required in the second stage of the procedure. Among them, allograft bone, β-tricalcium phosphate, bioactive glass, titanium and tantalum can replace autogenous bone as grafts, and other materials need to be mixed with autogenous bone, in both clinical and fundamental experiments. (4) Biomimetic-induced membranes, human amnion, human decellularized dermis, polytetrafluoroethylene, and even autogenous cortical bone have been shown to possess properties similar to the induced membrane. (5) Most of the application and research of biomaterials in this technology still exist in the stage of basic research and have not been applied in clinical practice or popularized on a large scale, but the above materials can provide more sufficient theoretical basis and new ideas for the exploration of Masquelet technical mechanism, the improvement of surgical methods and clinical application. [ABSTRACT FROM AUTHOR]

This study investigated the potential of 316L stainless steel coated with bioactive glasses for orthopedic implants by analyzing their corrosion resistance. To achieve this goal, novel bioglass compositions (BGs) were synthesized using the hydrothermal method and characterized using various techniques, including FTIR, XRD, SEM-EDS, and BET. The results confirmed that the bioglasses were amorphous and had surface porosity with a nanometric average size of about 40 to 47 nm. The bioglasses' bioactivity was assessed by immersing them in simulated body fluid (SBF) for up to 14 days. The 15-7510P bioglass displayed the highest acellular bioactivity, as evidenced by the rapid formation of a thick and continuous apatite layer on bioactive glass particles. Furthermore, the electrochemical corrosion behavior of 316L stainless steel substrate coated with bioactive glasses was evaluated using polarization and impedance in SBF solution at 37 °C and significantly improved compared to virgin 316 SS. The results showed that at 30 V with 0.5 g L−1 of Cs, 4 g L−1 of BG, and a deposition time of 10 min, the corrosion resistance of 316 SS was improved by the bioactive glass 15-7510P/chitosan coating composite. Cell viability and cytotoxicity of bioactive glasses were also analyzed using DPSCs and GMSM-K. The results demonstrated that the bioactive glasses had no harmful effects on cell viability. [ABSTRACT FROM AUTHOR]

Chronic periodontitis poses long-term challenges in dentistry, requiring the development of innovative dental composites with biocompatibility, bone regeneration, and antibacterial properties. This study focuses on synthesis of novel injectable thermoresponsive hydrogels composed of chitosan, sodium bicarbonate, bioactive glass (20 and 40% w/w), and acetanilide drug (0.3 and 0.6% w/w). These hydrogels exhibit a sol-gel transition at 37°C, addressing periodontal challenges with reduced gelation time. The smooth flow characteristic was evaluated through 17-22 gauge syringe needles at low temperature. Rheological studies demonstrated pseudoplastic behavior, with viscosity decreasing as shear rate increases. Fourier transform infrared and x-ray diffraction analysis confirmed the bioactivity of hydrogels, forming a bone-like apatite layer in simulated body fluid. The drug-loaded hydrogels demonstrated promising in vitro antibacterial properties against dental pathogens, specifically Staphylococcus aureus and Pseudomonas aeruginosa. Drug dissolution analysis revealed relatively high release rate at 37°C, highlighting its role in rapidly eliminating bacterial colonies at the target site, while the subsequent sustained release contributes to the prevention of infection recurrence. Finally, biocompatibility was assessed with fibroblast, where the cells were observed anchoring into the polymeric chains of hydrogel through extended filopodia. [ABSTRACT FROM AUTHOR]

Introduction: Esophageal stenting is a widely used treatment for esophageal diseases, which can also be used for adjuvant therapy and feeding after chemotherapy for esophageal cancer. The structural parameters of the stent have a significant impact on its mechanical properties and patient comfort. Methods: In the present work, we reconstructed the esophagus model based on the patient's computed tomography (CT) data, and designed stents with different structural parameters. We used 3D printing technology to achieve rapid production of the designed stents by using Thermoplastic polyurethane (TPU)/ Poly-ε-caprolactone (PCL) blends as the materials. The mechanical properties and effects on the esophagus of polymer stents with four different structural parameters of diameter, wall thickness, length and flaring were investigated by in vitro tests of radial compression and migration of the stents, as well as by finite element simulations of the stent implantation process in the esophagus and of the stent migration process. An artificial neural network model was established to predict the radial force of the stent and the maximum equivalent stress of the esophagus during implantation based on these four structural parameters. Results: The results show that wall thickness was the structural parameter that had the greatest impact on the radial force of the stent (statistically significant, p < 0.01), and flaring was the structural parameter that had the greatest impact on the maximum equivalent stress of the esophageal wall after stent implantation (statistically significant, p < 0.01). No. 6 stent had a maximum radial force of 18.07 N, which exceeded that of commercial esophageal stents and had good mechanical properties. And the maximum equivalent force on the esophagus caused by its implantation was only 30.39 kPa, which can improve patient comfort. The predicted values of the constructed back propagation (BP) neural network model had an error of less than 10% from the true values, and the overall prediction accuracies were both above 97%, which can provide guidance for optimizing the design of the stent and for clinical research. Discussion: 3D printing technology presents a wide range of applications for the rapid fabrication of personalized TPU/PCL blend stents that are more suitable for individual patients. [ABSTRACT FROM AUTHOR]

Inorganic–organic hybrid biomaterials have been proposed for bone tissue repair, with improved mechanical flexibility compared with scaffolds fabricated from bioceramics. However, obtaining hybrids with osteoinductive properties equivalent to those of bioceramics is still a challenge. In this work, we present for the first time the synthesis of a class II hybrid modified with bioactive glass nanoparticles (nBGs) with osteoinductive properties. The nanocomposite hybrids were produced by incorporating nBGs in situ into a polytetrahydrofuran (PTHF) and silica (SiO2) hybrid synthesis mixture using a combined sol–gel and cationic polymerization method. nBGs ~80 nm in size were synthesized using the sol–gel technique. The structure, composition, morphology, and mechanical properties of the resulting materials were characterized using ATR-FTIR, 29Si MAS NMR, SEM-EDX, AFM, TGA, DSC, mechanical, and DMA testing. The in vitro bioactivity and degradability of the hybrids were assessed in simulated body fluid (SBF) and PBS, respectively. Cytocompatibility with mesenchymal stem cells was assessed using MTS and cell adhesion assays. Osteogenic differentiation was determined using the alkaline phosphatase activity (ALP), as well as the gene expression of Runx2 and Osterix markers. Hybrids loaded with 5, 10, and 15% of nBGs retained the mechanical flexibility of the PTHF–SiO2 matrix and improved its ability to promote the formation of bone-like apatite in SBF. The nBGs did not impair cell viability, increased the ALP activity, and upregulated the expression of Runx2 and Osterix. These results demonstrate that nBGs are an effective osteoinductive nanoadditive for the production of class II hybrid materials with enhanced properties for bone tissue regeneration. [ABSTRACT FROM AUTHOR]

This study evaluated the biological response of cold-sprayed coatings composed of bioactive glass 45S5 and polyetheretherketone (PEEK). The functional coatings were produced by cold gas spray (CGS) technology, a technique that allows the deposition of powders at significantly low temperatures, avoiding heat damage to polymeric surfaces. By CGS, blends with different ratios of bioactive glass and PEEK powders have been deposited onto PEEK substrates to improve the response of the bio-inert polymer. The bioactivity of the coatings when immersed in a simulated body fluid solution was evaluated by observation with scanning electron microscopy (SEM) and x-ray diffraction (XRD). Results verify that bioactive glass particles in the composite coatings enhance their bioactivity. A degradation test was performed with Tris–HCl solution. From the results obtained by inductively coupled plasma optical emission spectroscopy (ICP-OES) and the weight loss of the samples, it was noticed that the degradation was directly related to the amount of glass in the coatings. Finally, the ability of bone-forming cells to adhere and proliferate on the coatings was evaluated. These experiments showed that the presence of glass particles does not cause a significant increase in cell proliferation. Combining a bioactive material with PEEK leads to forming a final component that provides suitable bioactivity to the final implant. [ABSTRACT FROM AUTHOR]

In recent decades, the requirements for implantable medical devices have increased, but the risks of implant rejection still exist. These issues are primarily associated with poor osseointegration, leading to biofilm formation on the implant surface. This study focuses on addressing these issues by developing a biomaterial for implant coatings. 45S5 bioglass® has been widely used in tissue engineering due to its ability to form a hydroxyapatite layer, ensuring a strong bond between the hard tissue and the bioglass. In this context, 45S5 bioglasses®, modified by the incorporation of different amounts of copper oxide, from 0 to 8 mol%, were synthesized by the melt–quenching technique. The incorporation of Cu ions did not show a significant change in the glass structure. Since the bioglass exhibited the capacity for being polarized, thereby promoting the osseointegration effectiveness, the electrical properties of the prepared samples were studied using the impedance spectroscopy method, in the frequency range of 102–106 Hz and temperature range of 200–400 K. The effects of CuO on charge transport mobility were investigated. Additionally, the bioactivity of the modified bioglasses was evaluated through immersion tests in simulated body fluid. The results revealed the initiation of a Ca–P-rich layer formation on the surface within 24 h, indicating the potential of the bioglasses to enhance the bone regeneration process. [ABSTRACT FROM AUTHOR]

The three-dimensional (3D) printing of biomaterials, cells, and bioactive components, including growth factors, has gained interest among researchers in the field of tissue engineering (TE) with the aim of developing many scaffolds to sustain size, shape fidelity, and structure and retain viable cells inside a network. The biocompatible hydrogel employed in 3D printing should be soft enough to accommodate cell survival. At the same time, the gel should be mechanically strong to avoid the leakage of cells into the surrounding medium. Considering these basic criteria, researchers have developed nanocomposite-based printable inks with suitable mechanical and electroconductive properties. These nanomaterials, including carbon family nanomaterials, transition metal dichalcogenides, and polymeric nanoparticles, act as nanofillers and dissipate stress across polymeric networks through their electroactive interactions. Nanofiber-reinforced printable ink is one kind of nanocomposite-based ink that comprises dispersed nanofiber components in a hydrogel matrix. In this current review, we compile various TE applications of nanofiber-reinforced printable ink and describe the 3D-printing parameters, classification, and impact of cross-linkage. Furthermore, we discuss the challenges and future perspectives in this field. [ABSTRACT FROM AUTHOR]

This study aimed to compare two types of bioactive additives which were strontium-containing fluorinated bioactive glass (SrBGF) or strontium-containing fluorapatite (SrFA) added to sol-gel derived glass ionomer cement (SGIC). The objective was to develop antibacterial and mineralisation properties, using bioactive additives, to minimize the occurrence of caries lesions in caries disease. Synthesized SrBGF and SrFA nanoparticles were added to SGIC at 1 wt% concentration to improve antibacterial properties against S. mutans, promote remineralisation, and hASCs and hDPSCs viability. Surface roughness and ion-releasing behavior were also evaluated to clarify the effect on the materials. Antibacterial activity was measured via agar disc diffusion and bacterial adhesion. Remineralisation ability was assessed by applying the material to demineralised teeth and subjecting them to a 14-day pH cycle, followed by microCT and SEM-EDS analysis. The addition of SrFA into SGIC significantly improved its antibacterial property. SGIC modified with either SrBGF or SrFA additives could similarly induce apatite crystal precipitation onto demineralised dentin and increase dentin density, indicating its ability to remineralise dentin. Moreover, this study also showed that SGIC modified with SrBGF or SrFA additives had promising results on the in vitro cytotoxicity of hASC and hDPSC. SrFA has superior antibacterial property as compared to SrBGF while demonstrating equal remineralisation ability. Furthermore, the modified SGIC showed promising results in reducing the cytotoxicity of hASCs and hDPSCs, indicating its potential for managing caries. ● Adding Strontium-containing fluorapatite (SrFA) in sol-gel glass ionomer cement (SGIC) improved the antibacterial property. ● Adding SrFA or strontium-containing fluorapatite (SrBGF) to SGIC similarly enhanced mineralization ability. ● All SGIC express promising results on the viability of human adipose-derived stem cells and human dental pulp stem cells. [ABSTRACT FROM AUTHOR]

Mesoporous bioactive glass nanoparticles (MBGNs) have attracted significant attention as multifunctional nanocarriers for various applications in both hard and soft tissue engineering. In this study, multifunctional strontium (Sr)- and zinc (Zn)-containing MBGNs were successfully synthesized via the microemulsion-assisted sol–gel method combined with a cationic surfactant (cetyltrimethylammonium bromide, CTAB). Sr-MBGNs, Zn-MBGNs, and Sr-Zn-MBGNs exhibited spherical shapes in the nanoscale range of 100 ± 20 nm with a mesoporous structure. Sr and Zn were co-substituted in MBGNs (60SiO2-40CaO) to induce osteogenic potential and antibacterial properties without altering their size, morphology, negative surface charge, amorphous nature, mesoporous structure, and pore size. The synthesized MBGNs facilitated bioactivity by promoting the formation of an apatite-like layer on the surface of the particles after immersion in Simulated Body Fluid (SBF). The effect of the particles on the metabolic activity of human mesenchymal stem cells was concentration-dependent. The hMSCs exposed to Sr-MBGNs, Zn-MBGNs, and Sr-Zn-MBGNs at 200 μg/mL enhanced calcium deposition and osteogenic differentiation without osteogenic supplements. Moreover, the cellular uptake and internalization of Sr-MBGNs, Zn-MBGNs, and Sr-Zn-MBGNs in hMSCs were observed. These novel particles, which exhibited multiple functionalities, including promoting bone regeneration, delivering therapeutic ions intracellularly, and inhibiting the growth of Staphylococcus aureus and Escherichia coli, are potential nanocarriers for bone regeneration applications. [ABSTRACT FROM AUTHOR]

The natural gas hydrate has become one of the most promising future green energy sources on the earth. The natural gas hydrates mostly exist in the sediments with porous structure, so a solid understanding of the hydrate formation and growth processes in the porous medium is of significance for the exploitation of natural gas hydrate. The micro-packed bed device is one of the efficient microfluidic devices in the engineering field, but it has been rarely used for the hydrate-based research. In this study, a transparent micro-packed bed device filled with glass beads was developed to mimic the porous condition of sediments, and used to in-situ visualize the hydrate formation and growth habits in the pore spaces under both static and dynamic conditions. For the static experiment, two types of hydrate growth patterns in porous medium were observed and identified in the micro-packed bed device, which were the graincoating growth and pore-filling growth. For the dynamic condition, the hydrate formation, growth, distribution habits and hydrate blockage phenomena in the pore spaces were in-situ visually captured. The impacts of flowrate and subcooling on the pressure variation of the micro-packed bed and the duration of the hydrate growth under dynamic flow condition in pores were in-situ monitored and analyzed. The higher flowrate could result in the faster hydrate growth and more severe blockage in pores, but the effect of subcooling condition might be less significant at the high flowrate. [ABSTRACT FROM AUTHOR]

Novel ceramic foams loaded with Fe and Fe/Mn oxides were developed via geopolymerization process as catalysts for tar removal in syngas cleaning operations. The foams were realized through polymer scaffold template replica, by impregnating polyurethane or cellulose foams with a metakaolin based geopolymer slurry loaded with 19 wt% powdered Fe 2 O 3 and Mn 2 O 3 metal oxides. A thermal treatment up to 900 °C was applied to vitrify and partially crystallize into leucite the geopolymer binder. Foams from cellulose showed better structural properties compared to those from polyurethane. Preliminary test in real gasification conditions were carried out on a lab scale double fixed bed reactor. In working conditions, vitrified phases derived from geopolymer binder promoted the formation of mixed phases of (Fe, Mn) oxides and silicates, beneficial for improving the catalytic activity. Furthermore, foams loaded with mixed Fe-Mn oxides were more effective than granules in reducing the produced tar. [ABSTRACT FROM AUTHOR]

Digital light processing (DLP), derived from stereolithography (SL), is a lithography-based additive manufacturing (AM) process that offers the ability to tailor scaffold shape, size, material, and biometrics of fabricated scaffolds to patient requirements. The additive manufacturing of tricalcium phosphate (TCP) bioceramic scaffolds via DLP is explored in the proceeding research paper. Particularly, the role of exposure intensity and exposure time on resultant scaffold quality and mechanical properties is studied. Increased exposure intensity results in an increased deviation from the designed lattice structure and thus an increase in compressive strength. Scaffolds produced with the highest exposure intensity, resulted in a 27.6 % error increase in mean beam diameter, resulting from an increased scattering effect, penetration depth, and over-curing of peripheral slurry. TCP scaffolds with an exposure time of 3.5 s and exposure intensity of 40 mW/cm2 possessed the highest print accuracy, resulting in the lowest average compressive strength – 82 MPa for the scaffolds of cube structure and 48 MPa for the ones of I-WP structure. Digital light processing (DLP) is an effective additive manufacturing (AM) method applicable for bioceramics. This study focuses on the influence of light exposure intensity on scaffold quality and compressive strength. The increase of exposure intensity can improve the compressive strength with the sacrifice of structure accuracy. The conclusions of this study can provide insights into the relationship of DLP printing parameters and scaffolds quality. [Display omitted] [ABSTRACT FROM AUTHOR]

Composite biomaterials were created by sintering soda-lime-silica glass powder and tetracalcium phosphate powder. Sintering of the samples at 1200 °C/2h led to the formation of wollastonite, calcium phosphate, and cristobalite before soaking in simulated body fluid (SBF). However, after soaking for two weeks in SBF the hydroxyapatite, wollastonite, and cristobalite phases appeared with relatively intense in hydroxyapatite phase on sample surfaces. The microstructure shows micro-scale particles on the sample surface after soaking in SBF. The bulk densities and porosities were within 1.82453–1.9672 g/cm3 and 15.0621–34.1657 % respectively whereas compressive strength values were between 42.79 and 111.26 MPa. Since the increase of the porosity in the direction of high addition of phosphate portion while strengths were high in opposite values. The biocompatibility in SBF increases with increasing the SLS glass portion and the SEM micrographs show fine spherical crystals, within 20–200 nm, of hydroxyapatite phase on composite surfaces. The FTIR spectrum after soaking in SBF indicates the presence of phosphate bands in all samples and the intensity of these bands increases as the SLS glass percentage increases. The degradation of composite samples decreases in the direction of an increase in the phosphate portion which led to a decrease in the porosity and an increase in both density and strength. Pseudomonas aeruginosa and Staphylococcus aureus, the two examined bacteria, both showed the establishment of growth inhibition zones in the disk diffusion assay. All samples were shown to be biocompatible by the cytotoxicity test conducted on the human normal fibroplast cell line (BJ1). In light of this, the cytotoxicity analysis demonstrated that the highest soda-lime-silica glass sample (SLP55), which has potential uses in the dental and bone fields, was entirely safe for use with the human normal fibroplast cell line (BJ1). [ABSTRACT FROM AUTHOR]

Iron (Fe) doped-mesoporous bioactive glasses are among the most promising candidates in cancer therapy; the present study reports the successful fabrication and characterization of a series of anticancer and pro-regenerative nanocomposites of polycaprolactone and gelatin nanofibers combined with Fe-doped mesoporous bioactive glasses. The anticancer potential and regenerative capacity of the prepared nanocomposite were studied on melanoma (A375 cell line) and normal fibroblast cells (L929 cell line) by using the MTT assay, annexin V/PI apoptosis assay, intracellular reactive oxygen species (ROS) generation, malondialdehyde assay, as well as adhesion and migration assessments. The characterization of the nanofibers containing 20 % (wt.%) glass particles revealed a suitable tensile strength (5.8 MPa), controlled swelling (355.5 % after 24 hours), and degradability (31.33 % after 28 days). The viability of A375 cells was significantly reduced (up to 77 %) after treatment with the 20 % glass-impregnated nanofibers along with 58 % and 8 % increase in their apoptosis and necrosis, respectively. Interestingly, this nanocomposite showed no significant adverse effects on normal fibroblasts. In conclusion, this study suggests the possibility of the bioactive glass nanoparticles/electrospun nanofiber composites in the treatment of cancers (e.g., melanoma) as well as in providing a suitable microenvironment for tissue repair and regeneration. However, performing in vivo studies is required to provide clear evidence of the anticancer potential of this nanocomposite system. [ABSTRACT FROM AUTHOR]

The application of porous bioactive ceramics as bone substitutes requires their effective osseointegration, which relies on specific physical and biological properties. In this study, we developed porous magnesium-doped hydroxyapatite (MgHA) ceramics with four different magnesium concentrations (0.25, 2, 5 and 10 mol%). The ceramics were prepared through the polymeric replication sponge method and subjected to physical and biological characterizations. Upon sintering, the porous 10 mol% MgHA ceramics exhibited increased densification, which resulted in the highest compressive strength of 2.17 MPa at the lowest porosity of 31 %. The porous samples were analysed via microcomputed tomography. The scaffolds with 0.25 and 10 mol% Mg doping concentrations were selected to elucidate the influence of Mg on morphometric parameters and biological properties at two distinct levels. The high level of Mg doping led to considerable improvements in relative bone volume, connectivity density, trabecular number and trabecular thickness. Cell attachment and proliferation tests using Vero cell lines were conducted on both samples to investigate the correlations between their morphometric parameters and bioactivities. Substantially more cells attached to and proliferated on the surface of the 10 mol% MgHA ceramics compared with those on the ceramics containing 0.25 mol% MgHA. In summary, our study underscores the effectiveness of Mg incorporation in improving the physical and biological properties of porous HA ceramics, which makes them promising candidates for bone substitute applications. [ABSTRACT FROM AUTHOR]

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Zirconia-based dental implants are in direct contact with living tissues and any improvements in their bioactivity and adhesion to the tissues are highly welcome. In this study, different ratios of barium titanate (BT) were added to 3 mol% yttria-stabilized zirconia (3YSZ) through conventional sintering. The laser-texturing technique was also conducted to improve the biological performance of 3YSZ ceramics. The composition and the surface of the prepared composites were characterized by X-ray diffraction and scanning electron microscopy (SEM), respectively. The roughness and surface wettability of the composites were also measured. Furthermore, MC3T3-E1 pre-osteoblast cells were used for the in vitro experiments. Cell viability was evaluated using a commercial resazurin-based method. Morphology and cellular adhesion were observed using SEM. Based on the results, the laser texturing and the barium titanate content influenced the surface characteristics of the prepared composites. The laser-textured 3YSZ/7 mol% BT composites showed a lower water contact angle compared to the other samples, which indicated superior surface hydrophilicity. The cell viability and cell adhesion of 3YSZ/BT composites increased with the rise in the barium titanate content and laser power. An elongated cell morphology and apatite nucleation were also observed by the BT content. Overall, the laser-treated 3YSZ/5 and 7 mol% BT composites may be promising candidates in hard tissue repair due to their good cell response. [ABSTRACT FROM AUTHOR]

Aim: Endodontic sealers with antimicrobial impact are considered relevant to prevent re-infection and ensure healing of damaged periapical tissue. Hence, this study aimed to assist the antimicrobial effect of newly developed nano-tricalcium silicate-58s bioactive glass (BG)-based endodontic sealer (C3S-BG-P), and compare its results with Nishika Canal Sealer BG and BioRoot™ oot canal sealer (RCS). Methods: The antimicrobial impact of endodontic sealers was evaluated by both agar diffusion test (ADT) and direct contact test (DCT) against Enterococcus faecalis and Candida albicans. In ADT, the diameter of inhibition zones was measured after 1, 2, and 3 days of incubation using Digimizer software program. In DCT, the sealers were allowed to set for 1, 7, and 14 days and then exposed to the microbial suspension for 24 h. The colony-forming unit was counted using ImageJ software program. The data were analyzed with ANOVA and Tukey's tests. Results: In ADT, all the tested sealers showed antimicrobial effect after 3 days, with no significant difference after 1 day, but the impact of C3S-BG-P and Nishika significantly higher than that of BioRoot after 2 and 3 days. In DCT, C3S-BG-P and Nishika had an antimicrobial effect against both isolates even after 14 days of their setting, whereas BioRoot had an effect for 7 days of its setting and lost its impact after 14 days. Conclusion: C3S-BG-P explored antimicrobial impact superior to that of BioRoot and nearly comparable to that of Nishika against E. faecalis and C. albicans, which last even after 14 days of its setting. [ABSTRACT FROM AUTHOR]

Bone tissue engineering (BTE) is a biomedical area that develops scaffolds capable of mimicking and repairing damage on bone tissue. For this, a popular and nonexpensive 3D printing technique named fused deposition modeling (FDM) has been used. The potential use of 3D scaffolds of poly(butylene adipate-co-terephthalate (PBAT) has been investigated in BTE since this polymer presents good biocompatibility and degradability, as well as mechanical properties like those offered by the natural bone. A single material does not have the features to promote cell adhesion, proliferation, and differentiation; the incorporation of bioactive substances can overcome this issue. This work aimed to develop 3D printed PBAT scaffolds by FDM technique and coated them with hydroxyapatite (H), bioglass (B), and gelatin (G) by solution immersion technique to obtain a functional biomaterial to be applied on the BTE. Structural characteristics and morphological and mechanical properties of the 3D scaffolds were evaluated. The cell proliferation and mineralization of pre-osteoblastic cells (MC3T3-E1) were accessed by methylthiazolyldiphenyl-tetrazolium bromide, sulphorodhamine B, and Alizarin red assay, respectively. 3D printed PBAT scaffolds were successfully obtained by FDM, and the surface modification of 3D PBAT was proven through the changes observed in structural and morphological characteristics. In addition, the mechanical properties were improved in the modified scaffolds. Also, the coated 3D PBAT scaffolds with any bioactive substance increased and promoted cell proliferation and pre-osteoblastic differentiation. Therefore, the combination of 3D PBAT scaffolds and H, G, and/or B (doped with niobium) is an alternative to produce functional biomaterials for BTE. [ABSTRACT FROM AUTHOR]

This study aimed to develop gelatin methacryloyl (GelMA)-injectable hydrogels incorporated with 58S bioactive glass/BG-doped with strontium for vital pulp therapy applications. GelMA hydrogels containing 0% (control), 5%, 10%, and 20% BG (w/v) were prepared. Their morphological and chemical properties were evaluated by scanning electron microscopy/SEM, energy dispersive spectroscopy/EDS, and Fourier transform infrared spectroscopy/FTIR (n = 3). Their swelling capacity and degradation ratio were also measured (n = 4). Cell viability (n = 8), mineralized matrix formation, cell adhesion, and spreading (n = 6) on DPSCs were evaluated. Data were analyzed using ANOVA/post hoc tests (α = 5%). SEM and EDS characterization confirmed the incorporation of BG particles into the hydrogel matrix, showing GelMA's (C, O) and BG's (Si, Cl, Na, Sr) chemical elements. FTIR revealed the main chemical groups of GelMA and BG, as ~1000 cm−1 corresponds to Si-O and ~1440 cm−1 to C-H. All the formulations were degraded by day 12, with a lower degradation ratio observed for GelMA+BG20%. Increasing the concentration of BG resulted in a lower mass swelling ratio. Biologically, all the groups were compatible with cells (p > 0.6196), and cell adhesion increased over time, irrespective of BG concentration, indicating great biocompatibility. GelMA+BG5% demonstrated a higher deposition of mineral nodules over 21 days (p < 0.0001), evidencing the osteogenic potential of hydrogels. GelMA hydrogels incorporated with BG present great cytocompatibility, support cell adhesion, and have a clinically relevant degradation profile and suitable mineralization potential, supporting their therapeutic potential as promising biomaterials for pulp capping. [ABSTRACT FROM AUTHOR]

This study investigated the incorporation of sources of calcium, phosphate, or both into electrospun scaffolds and evaluated their bioactivity on human dental pulp cells (HDPCs). Additionally, scaffolds incorporated with calcium hydroxide (CH) were characterized for degradation, calcium release, and odontogenic differentiation by HDPCs. Polycaprolactone (PCL) was electrospun with or without 0.5% w/v of calcium hydroxide (PCL + CH), nano-hydroxyapatite (PCL + nHA), or β-glycerophosphate (PCL + βGP). SEM/EDS analysis confirmed fibrillar morphology and particle incorporation. HDPCs were cultured on the scaffolds to assess cell viability, adhesion, spreading, and mineralized matrix formation. PCL + CH was also evaluated for gene expression of odontogenic markers (RT-qPCR). Data were submitted to ANOVA and Student's t-test (α = 5%). Added CH increased fiber diameter and interfibrillar spacing, whereas βGP decreased both. PCL + CH and PCL + nHA improved HDPC viability, adhesion, and proliferation. Mineralization was increased eightfold with PCL + CH. Scaffolds containing CH gradually degraded over six months, with calcium release within the first 140 days. CH incorporation upregulated DSPP and DMP1 expression after 7 and 14 days. In conclusion, CH- and nHA-laden PCL fiber scaffolds were cytocompatible and promoted HDPC adhesion, proliferation, and mineralized matrix deposition. PCL + CH scaffolds exhibit a slow degradation profile, providing sustained calcium release and stimulating HDPCs to upregulate odontogenesis marker genes. [ABSTRACT FROM AUTHOR]

This document is an editorial introducing a special issue of the journal "Crystals" titled "Advances in New Functional Biomaterials for Medical Applications." The editorial highlights the historical development of biomaterials and their evolution from ancient civilizations to the present day. It discusses the three generations of biomaterials, emphasizing the current era of dynamic and intelligent systems that can respond to biological stimuli. The editorial also provides an overview of the articles included in the special issue, which cover topics such as biocompatible materials, surface modifications, bioceramics, coatings, synthesis techniques, and biomaterials for theranostics and tissue engineering. The document concludes by acknowledging the contributions of the authors and peer reviewers to the special issue. [Extracted from the article]

Coronavirus disease 2019 (COVID-19), caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2 or 2019-nCoV), is a life-threatening infectious condition. Acute lung injury is a common complication in patients with COVID-19. 3-chymotrypsin-like protease (3CLpro) of 2019-nCoV and neutrophil elastase are critical targets of COVID-19 and acute lung injury, respectively. Colchicine and magnolol are reported to exert inhibitory effects on inflammatory response, the severe comorbidity in both COVID-19 and acute lung injury. We thus designed and synthesized a series of novel colchicine-magnolol hybrids based on a two-step synthetic sequence. It was found that these novel hybrids provided unexpected inhibition on 3CLpro and neutrophil elastase, a bioactivity that colchicine and magnolol did not possess. These findings not only provide perquisites for further in vitro and in vivo investigation to confirm the therapeutic potentiality of novel colchicine-magnolol hybrids, but also suggest that the concurrent inhibition of 3CLpro and neutrophil elastase may enable novel colchicine-magnolol hybrids as effective multi-target drug compounds. [ABSTRACT FROM AUTHOR]

Aging is a risk factor for human health and quality of life. Screening and development of novel supplements and medications to combat aging and delay the incidence of age-related diseases are of great significance. In this study, salidroside (SA), a primary natural small molecule from Rhodiola rosea, was investigated regarding its effects on life and healthspan and the underlying molecular mechanism(s) of anti-aging and antioxidation. Our results showed that SA effectively prolonged lifespan and exhibited anti-aging and antioxidative properties. Computer-assisted methods, label-free interaction analysis, and in vitro assays showed that SA directly bound heat shock protein 90 (HSP90). Furthermore, SA significantly inhibited the ATPase activity of HSP90, affecting the interaction between HSP90 and its interacting proteins and the expression of downstream genes to regulate lifespan and the oxidative stress response. Our findings provided new insights into the pharmacological properties of SA across multiple species and its potential as an anti-aging drug. [ABSTRACT FROM AUTHOR]

Many countries face the problem of agroindustrial waste elimination, which is linked to environmental damage caused by improper waste management. These wastes contain bioactive compounds often discarded due to a lack of knowledge. The objective of this study was to analyze five types of agroindustrial waste from Peru, including avocado (Persea americana) seeds, lucuma (Pouteria lucuma) seeds, grape (Vitis vinifera) pomace, mango (Mangifera indica) peel, and cocoa (Theobroma cacao) pods. This study includes proximal analysis, determination of total phenolic compound content, analysis of phenolic compounds by UHPLC-Q/Orbitrap/ESIMS/MS (Ultrahigh-performance liquid chromatography-electrospray ionization Q-Orbitrap mass spectrometry), and the evaluation of antioxidant, antimicrobial, and antifungal activities of different samples. The results showed that lucuma seeds had the highest protein content of 6.59 g/100 g DW. Mango peels showed the highest fat content of 4.89 g/100 g DW, cocoa pods had the highest crude fiber content of 26.91 g/100 g DW, and cocoa pods exhibited the highest ash content of 7.14 g/100 g DW. The highest carbohydrate content was found in avocado seeds at 85.85 g/100 g DW. Mango peels (56.66 mg GAE/g DW), avocado seeds (56.35 mg GAE/g DW), and cocoa pods (51.52 mg GAE/g DW) extracts showed the highest phenolic compound contents. Mango peel extract exhibited the highest antioxidant activities evaluated by the ABTS (995.01 µmol TEAC/g DW), DPPH (953.54 µmol TEAC/g DW), and FRAP (1661.13 µmol TEAC/g DW) assays. Extracts from cocoa pods, grape pomace, and lucuma seeds showed inhibitory activity on the growth of Staphylococcus aureus and Escherichia coli. In contrast, the extract of lucuma seeds was the only one that showed antifungal activity over Penicillium digitatum. As a result, several phenolic compounds were detected in each, indicating their potential use in developing functional foods and food preservation, among other applications. [ABSTRACT FROM AUTHOR]

Calcium-containing organic–inorganic nanocomposites play an essential role in developing bioactive bone biomaterials. Ideally, bone substitute materials should mimic the organic–inorganic composition of bone. In this study, the roles of calcium chloride (CaCl2) and calcium ethoxide (Ca(OEt)2) were evaluated for the development of sol-gel-derived organic–inorganic biomaterials composed of gelatin, bioactive glass (BG) and multiwall carbon nanotubes (MWCNTs) to create nanocomposites that mimic the elemental composition of bone. Nanocomposites composed of either CaCl2 or Ca(OEt)2 were chemically different but presented uniform elemental distribution. The role of calcium sources in the matrix of the nanocomposites played a major role in the swelling and degradation properties of biomaterials as a function of time, as well as the resulting porous properties of the nanocomposites. Regardless of the calcium source type, biomineralization in simulated body fluid and favorable cell attachment were promoted on the nanocomposites. 10T1/2 cell viability studies using standard media (DMEM with 5% FBS) and conditioned media showed that Ca(OEt)2-based nanocomposites seemed more favorable biomaterials. Collectively, our study demonstrated that CaCl2 and Ca(OEt)2 could be used to prepare sol-gel-derived gelatin–BG–MWCNT nanocomposites, which have the potential to function as bone biomaterials. [ABSTRACT FROM AUTHOR]