Development of a novel Ga-containing hydroxyapatite/chlorhexidine biomaterial with antibacterial properties for future application in bone tissue engineering: an experimental and theoretical study

Jellyfish collagen serves as a competitive alternative to mammalian-sourced collagen in many practical aspects. For instance, jellyfish collagen lacks religious constraints when compared to bovine or porcine sources and promises batch-to-batch consistency. Another advantage is its structural similarity with many mammalian collagen types, providing a biocompatible matrix for different cell types as "collagen type 0". This paper intends to investigate jellyfish collagen (Jellagen®) in two applications. This investigation aims to establish an initial understanding of jellyfish collagen in biotechnology. More specifically, in cell culture and the field of tissue engineering. The jellyfish collagen was comparatively tested as a coating material for multi-well plates as one of the most extensively used tools in cell culture and in the form of three-dimensional (3D) scaffolds intended for bone tissue engineering (BTE) applications. Both, the coated well plates and the scaffolds were seeded with fibroblasts and pre-osteoblasts, separately. In vitro cytocompatibility assays in accordance with EN ISO 10993-5/-12 regulations and LIVE-DEAD-stainings were carried out to study the cell viability, cytotoxicity and proliferation of these two cell lines. The results showed that collagen extracted from R. pulmo jellyfish can be an alternative to mammalian-derived collagen. Fibroblasts showed comparable cell viability to the medium control and an increased cell proliferation on the well plates indicating that these coated well plates can be used in cell culture, particularly in biocompatibility studies of biomaterials (as fibroblasts are used in this respective field extensively). The viability of pre-osteoblasts significantly exceeded the medium control in case of the jellyfish 3D scaffolds. These cells exhibited favorable healthy behavior on this marine collagen, suggesting that Jellagen® collagen can be used in studies of (bone) tissue regeneration and especially as scaffolds in BTE. In conclusion, jellyfish collagen provides biocompatibility and adhesive properties for both cell culture and BTE applications.

Bone tissue engineering (BTE) applications and regenerative strategies have been used to improve the clinical practice of repairing large bone defects associated with surgical resections, congenital malformations, and trauma. The scaffolds are designed to stimulate a biological response, including cell interactions, and guide tissue regeneration by functioning as artificial biomimetic extracellular matrixes. Polymeric biomaterials are suitable for bone tissue engineering since they possess both chemical and physical properties, enabling the control of shape, morphology, and biodegradability, which makes them suitable for bone regeneration and tissue engineering applications. In vivo animal models were studied for collagen, chitosan, poly (lactic acid) (PLA) and high density polyethylene (HDPE), the four most common polymers employed in bone tissue engineering. Through analysis of the results of this review, the in vivo studies can provide a large-scale evaluation of the possibility of achieving optimal bone-forming capabilities and regenerative capabilities. Furthermore, the review will serve as an essential reference for bone tissue engineering applications as well as contribute to the development of novel in vivo investigations

Introduction: Bone tissue engineering seeks innovative materials that support cell growth and regeneration. Electrospun nanofibers, with their high surface area and tunable properties, serve as promising scaffolds. This study explores the incorporation of flaxseed extract, rich in polyphenolic compounds, into polyvinyl alcohol (PVA) nanofibers to improve their application in bone tissue engineering. Methods: High-performance liquid chromatography (HPLC) identified ten key compounds in flaxseed extract, including polyphenolic acids and flavonoids. PVA nanofibers were fabricated with 30 wt.% flaxseed extract (P70/E30) via electrospinning. We optimized characteristics like diameter, hydrophilicity, swelling behavior, and hydrolytic degradation. MG-63 osteoblast cultures were used to assess scaffold efficacy through cell adhesion, proliferation, viability (MTT assay), and differentiation. RT-qPCR measured expression of osteogenic genes RUNX2, COL1A1, and OCN. Results: Flaxseed extract increased nanofiber diameter from 252nm (pure PVA) to 435nm (P70/E30). P70/E30 nanofibers showed higher cell viability (102.6% vs. 74.5% for pure PVA), although adhesion decreased (151 vs. 206 cells/section). Notably, P70/E30 enhanced osteoblast differentiation, significantly upregulating RUNX2, COL1A1, and OCN genes. Discussion: Flaxseed extract incorporation into PVA nanofibers enhances bone tissue engineering by boosting osteoblast proliferation and differentiation, despite reduced adhesion. These properties suggest P70/E30's potential for regenerative medicine, emphasizing scaffold optimization for biomedical applications.

The potential of human fetal mesenchymal stem cells for off-the-shelf bone tissue engineering application

Texturally-enhanced 55S0P and 45S10P Bioactive Glass ceramic particles: Sol-gel fabrication, nano-characterization and comprehensive Bio-evaluation for applications in Bone tissue engineering

Bone repair and regeneration following an injury still present challenges worldwide. Three-dimensional (3D) scaffolds made from various materials are used for bone tissue engineering (BTE) applications. Polymers, minerals and nanotechnology are now being used in combination to achieve specific goals for BTE, including the delivery of antimicrobials through the scaffolds to prevent post-surgical infection. While several materials are utilised for BTE, natural polymers present a unique set of materials that can be manipulated to formulate scaffolds for BTE applications. They have been found to demonstrate higher biocompatibility, biodegradability and lower toxicity. Some even naturally mimic the bone microarchitecture, providing inherent structural support for BTE. Natural polymers may be simply classified as those from plant and animal sources. From both sources, there are different types of proteins, polysaccharides and other specialised materials that are already in use for research in BTE. Interestingly, these have the potential to revolutionise the field of BTE with a sustainable approach. In this review, we first discuss the different natural polymers used in BTE from plant sources, followed by animal sources. We then explore novel materials that are aimed at sustainable approaches, focusing on innovation from the last decade. In these sections, we outline studies of these materials with different types of bone cells, including bone marrow mesenchymal stromal cells (MSCs), which are the progenitors of bone. We finally outline the limitations, conclusions and future directions from our perspective in this dynamic field of polymers in BTE. With this review, we hope to bring together the updated existing knowledge and the potential future of innovation and sustainability in natural polymers for biomimetic BTE applications for fellow scientists, researchers and surgeons in the field.

Injectable hydrogel provides an excellent substrate for bone tissue engineering (BTE) applications due to its water base, and capacity to encapsulate, manipulate, and easily reach to the adjacent tissue with minimal invasiveness. The purpose of the present study, is to develop an injectable hydrogel with a combination of chitosan, hyaluronic acid, and hydroxyapatite for enhanced bone regeneration and remodeling. Blend hydrogels have enough surface roughness and porosity that helps to attach bone cells. Hydrogel synthesis was confirmed with XRD, FTIR, EDX and TGA characterization. These hydrogels demonstrated adequate swelling and mechanical properties for its use in BTE applications. These hydrogels have the acceptable range of mechanical strength required for injectable hydrogels for bone regeneration. The synthesized hydrogel showed enough range of percolation capacity needed for the permeability of medicine, growth factors, and nutritional molecules. All these findings suggest the use of synthesized hydrogels for bone regeneration in biomedical engineering applications.

Bone fractures are a serious health problem worldwide, and up to 10% of emergency department visits are related to such injuries. The development of effective materials for bone repair remains an urgent need of modern medicine. The aim of this study was to develop new scaffolds based on biopolymers (methyl cellulose and hydroxyethyl cellulose) modified with carbonate nanoparticles (CaCO3, MgCO3, ZnCO3, MnCO3, CuCO3) for potential applications in bone tissue engineering. FTIR spectroscopy confirmed the successful formation of stable composite structures: characteristic absorption bands of the functional groups of the molecules that make up the scaffold, as well as specific fluctuations in metal-oxygen bonds (Ca–O, Zn–O, Cu–O), were revealed. Stability tests revealed the most stable samples when changing the pH and the ionic strength of the solution. The developed scaffold matrices had a high porosity in the range from 93.3% to 98.0%, and their moisture absorption capacity ranged from 858% to 1402%. Specific gravity measurements ranged from 0.050 g/cm3 to 0.067 g/cm3, indicating optimal material density for potential biomedical applications. Biological evaluation demonstrated different cytotoxic effects depending on the type of nanoparticles. Thus, matrices with minimal toxicity and promising biocompatibility (modified CaCO3), as well as with significant toxic effects (modified ZnCO3 and CuCO3) were found. As a result, it was found that CaCO3-modified scaffolds have the most favorable combination of structural, physical, and biological properties for potential applications in bone tissue engineering. The developed innovative materials are porous scaffolds in which nanoparticles of carbonates of osteotropic elements are embedded, which presumably contribute to the acceleration of bone tissue regeneration. However, this study provides encouraging preliminary data, and further in-depth biological and functional studies are needed to fully confirm the osteogenic potential and regenerative efficacy of the scaffolds.

Gelatin methacryloyl (GelMA)-based composites are evolving three-dimensional (3D) networking hydrophilic protein composite scaffolds with high water content. These protein composites have been devoted to biomedical applications due to their unique abilities, such as flexibility, soft structure, versatility, stimuli-responsiveness, biocompatibility, biodegradability, and others. They resemble the native extracellular matrix (ECM) thanks to their remarkable cell-adhesion and matrix-metalloproteinase (MMP)-responsive amino acid motifs. These favorable properties promote cells to proliferate and inflate within GelMA-protein scaffolds. The performance of GelMA composites has been enriched using cell-amenable components, including peptides and proteins with a high affinity to harmonize cellular activities and tissue morphologies. Due to their inimitable merits, GelMA systems have been used in various fields such as drug delivery, biosensor, the food industry, biomedical, and other health sectors. The current knowledge and the role of GelMA scaffolds in bone tissue engineering are limited. The rational design and development of novel nanomaterials-incorporated GelMA-based composites with unique physicochemical and biological advantages would be used to regulate cellular functionality and bone regeneration. Substantial challenges remain. This review focuses on recent progress in mitigating those disputes. The study opens with a brief introduction to bone tissue engineering and GelMA-based composites, followed by their potential applications in bone tissue engineering. The future perspectives and current challenges of GelMA composites are demonstrated. This review would guide the researchers to design and fabricate more efficient multifunctional GelMA-based composites with improved characteristics for their practical applications in bone tissue engineering and biomedical segments.

Dentin has become an interesting potential biomaterial for tissue engineering of oral hard tissues. It can be used as a scaffold or as a source of growth factors in bone tissue engineering. Different forms of dentin have been studied for their potential use as bone substitutes. Here, we systematically review different methods of dentin preparation and the efficacy of processed dentin in bone tissue engineering. An electronic search was carried out in PubMed and Scopus databases for articles published from 2000 to 2016. Studies on dentin preparation for application in bone tissue engineering were selected. The initial search yielded a total of 1045 articles, of which 37 were finally selected. Review of studies showed that demineralization was the most commonly used dentin preparation process for use in tissue engineering. Dentin extract, dentin particles (tooth ash), freeze-dried dentin, and denatured dentin are others method of dentin preparation. Based on our literature review, we can conclude that preparation procedure and the size and shape of dentin particles play an important role in its osteoinductive and osteoconductive properties. Standardization of these methods is important to draw a conclusion in this regard. © 2016 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 104A: 2616-2627, 2016.

Plant-derivedcellulose biomaterials have been employed in various tissue engineering applications. In vivo studies have shown the remarkable biocompatibility of scaffolds made of cellulose derived from natural sources. Additionally, these scaffolds possess structural characteristics that are relevant for multiple tissues, and they promote the invasion and proliferation of mammalian cells. Recent research using decellularized apple hypanthium tissue has demonstrated the similarity of its pore size to that of trabecular bone as well asits ability to effectively support osteogenic differentiation. The present study furtherexamined the potential of apple-derived cellulose scaffolds for bone tissue engineering (BTE) applications and evaluated their in vitro and in vivo mechanical properties. MC3T3-E1 preosteoblasts were seeded in apple-derived cellulose scaffolds that were thenassessed for their osteogenic potential and mechanical properties. Alkaline phosphatase and alizarin red S staining confirmed osteogenic differentiation in scaffolds cultured in differentiation medium. Histological examination demonstrated widespread cell invasion and mineralization across the scaffolds. Scanning electron microscopy (SEM) revealed mineral aggregates on the surface of the scaffolds, andenergy-dispersive spectroscopy (EDS)confirmed the presence of phosphate and calcium elements. However, despite a significant increase in the Young's modulus following cell differentiation, it remained lower than that of healthy bone tissue. In vivo studies showed cell infiltration and deposition of extracellular matrix within the decellularized apple-derivedscaffolds after 8 weeks of implantation in rat calvaria. In addition, the force required to remove the scaffolds from the bone defect was similar to the previously reported fracture load of native calvarial bone. Overall, this study confirms that apple-derived cellulose is a promising candidate for BTE applications. However, the dissimilarity between its mechanical properties and those of healthy bone tissue may restrict its application to low load-bearing scenarios. Additional structural re-engineering and optimization may be necessary to enhance the mechanical properties of apple-derived cellulose scaffolds for load-bearing applications.

Strontium sintered calcium sulfate bone graft for enhancing osteogenesis in a rat femoral defect model

Bone tissue engineering has emerged as a key approach to address orthopedic disorders. This study aimed to evaluate the effects of a composite nanofiber scaffold composed of polycaprolactone (PCL), polylactic acid (PLA) and hydroxyapatite (HA) on osteoblast viability, apoptosis and functional metabolism. Electrospun scaffolds of PCL/PLA, PCL/HA and PCL/PLA/HA were fabricated and analyzed by scanning electron microscopy (SEM) and Fourier transform infrared spectroscopy (FTIR). Cell proliferation was assessed via MTT assay, apoptosis through flow cytometry and alkaline phosphatase (ALP) activity via ATP assay. The PCL/PLA/HA scaffold exhibited smaller fiber diameters and promoted more prominent cell extensions compared to other groups. FTIR analysis confirmed component integration, with specific PCL peaks disappearing after composite formation. The PCL/PLA/HA scaffold significantly enhanced osteoblast proliferation and ALP expression (P<0.05) while reducing apoptosis rate. The PCL/PLA/HA composite nanoscaffold improves osteoblast function by promoting proliferation and metabolic activity while minimizing apoptosis. These findings support its potential application in bone tissue engineering.

The bone is a highly dynamic tissue with the remarkable ability to remodel and is in a continuous cycle of resorption and renewal as a result of internal mediators and external mechanical demands. Researchers have doubled their efforts to develop bone graft substitutes in order to overcome limitations that surround current bone loss treatment and the annual increase of cases dealing with bone loss and dysfunction. Chitosan has been identified by many researchers as a suitable biomaterial for bone tissue engineering applications. Chitosan holds various favourable properties, yet the mechanical strength of pure chitosan scaffolds hinders its application in bone tissue engineering. By combining chitosan with other materials, the advantageous properties can potentially be retained or even enhanced and limiting properties can be mediated. Chitosan has been blended in varying combinations with a variety of materials that include ceramics, synthetic polymers, natural polymers and other additives. This review will focus on chitosan-based biomaterials that have been developed for bone tissue engineering. The application of chitosan-based biomaterials in the bone tissue engineering field has become increasingly popular among researchers. Chitosan has many favourable properties; however, limitations have hindered its application in bone tissue engineering. To overcome these limitations, chitosan has been blended with other polymers (natural and synthetic), ceramics and other additives. These composite materials are combined to eliminate unfavourable properties and retain favourable properties.

In this study we investigated not only the cellular proliferation and osteogenic differentiation of human bone marrow stromal cells (hBMSCs) on the novel β-tricalcium phosphate (β-TCP) scaffolds in vitro but also bone formation by ectopic implantation in athymic mice in vivo. The interconnected porous β-TCP scaffolds with pores of 300–500 µm in size were prepared by the polymeric sponge method. β-TCP scaffolds with the dimension of 3 mm × 3 mm × 3 mm were combined with hBMSCs, and incubated with (+) or without (−) osteogenic medium in vitro. Cell proliferation and osteogenic differentiation on the scaffolds were evaluated by scanning electron microscopy (SEM) observation, MTT assay, alkaline phosphatase (ALP) activity and osteocalcin (OCN) content measurement. SEM observation showed that hBMSCs attached well on the scaffolds and proliferated rapidly. No significant difference in the MTT assay could be detected between the two groups, but the ALP activity and OCN content of scaffolds (+) were much higher than those of the scaffolds (−) (p < 0.05). These results indicated that the novel porous β-TCP scaffolds can support the proliferation and subsequent osteogenic differentiation of hBMSCs in vitro. After being cultured in vitro for 14 days, the scaffolds (+) and (−) were implanted into subcutaneous sites of athymic mice. In β-TCP scaffolds (+), woven bone formed after 4 weeks of implantation and osteogenesis progressed with time. Furthermore, tissue-engineered bone could be found at 8 weeks, and remodeled lamellar bone was also observed at 12 weeks. However, no bone formation could be found in β-TCP scaffolds (−) at each time point checked. The above findings illustrate that the novel porous β-TCP scaffolds developed in this work have prominent osteoconductive activity and the potential for applications in bone tissue engineering.