Effect of calcium silicate nanoparticle on surface feature of calcium phosphates hybrid bio-nanocomposite using for bone substitute application

Calcium silicate/gelatin composite scaffolds with controllable degradation behavior: Fabrication and evaluation

Calcium silicate can be used as an excellent material for biodegradable bone scaffolds because it can provide bioactive ions to promote bone regeneration. However, the brittleness and rapid degradation of calcium silicate scaffolds have significantly limited their clinical application. In this work, the calcium silicate scaffolds printed by DLP technology were immersed in a gelatin solution under high vacuum condition to obtain calcium silicate/gelatin composite scaffolds with good mechanical and biological properties. Then, genipin was used as a cross-linker for gelatin to control the degradation properties of the composite scaffolds. The initial compressive strength and toughness of the composite scaffolds were 5.0 times and one order of magnitude higher than those of the pure calcium silicate scaffolds, respectively. The gelatin on the surface of the scaffolds could effectively act as a protective layer to regulate the degradation behaviors of the calcium silicate substrate through controlling the crosslinking degree of the gelatin. After degrading for 14 days, the composite scaffolds at 1.0 % genipin concentration exhibited the highest compressive strength of 8.6 ± 0.8 MPa, much higher than that of the pure ceramic scaffold (1.5 ± 0.3 MPa). It can be found that the toughness of the composite scaffolds were almost over 13.2 times higher than that of the pure ceramic scaffold during degradation, despite the higher toughness loss for the former. Furthermore, the composite scaffolds showed enhanced cell biocompatibility and viability. These results demonstrate that the calcium silicate/gelatin composite scaffolds can be a promising candidate in bone tissue regeneration.

Tuning biodegradability, bone-bonding capacity, and wear resistance of zinc-30% magnesium intermetallic alloy for use in load-bearing bone applications

This work aimed to improve the rapid biodegradation, poor wear resistance properties, and lack of bioactivity of metallic biomaterials to be used in orthopedic applications. In this context, zinc-magnesium (Zn-Mg) alloy with successive contents of calcium silicate (CaSiO3) and silicon nitride (Si3N4) was prepared using powder metallurgy technique. After sintering, their phase composition and microstructure were investigated using the X-ray diffraction technique and scanning electron microscopy (SEM), respectively. Furthermore, their degradation behavior and ability to form hydroxyapatite (HA) layer on the sample surface after immersion in simulated body fluid (SBF) were monitored using weight loss measurements, inductively coupled plasma-atomic emission spectroscopy, and SEM. Moreover, their tribo-mechanical properties were measured. The results obtained showed that the successive contents of CaSiO3 were responsible for improving the bioactivity behavior as indicated by a good formation of the HA layer on the samples' surface. Additionally, ceramic materials were responsible for a continuous decrease in the released ions in the SBF solution as indicated by the ICP results. The tribology properties were significantly improved even after exposure to different loads. Based on the above results, the prepared nanocomposites are promising for use in orthopedic applications.

Horizon Scanning in Tissue Engineering Using Citation Network Analysis

BACKGROUND

Establishing a horizon scanning method is critical for identifying technologies that require new guidelines or regulations. We studied the application of bibliographic citation network analysis to horizon scanning.

OBJECTIVE

The possibility of applying the proposed method to interdisciplinary fields was investigated with the emphasis on tissue engineering and its example, three-dimensional bio-printing.

METHODOLOGY AND RESULTS

In all, 233,968 articles on tissue engineering, regenerative medicine, biofabrication, and additive manufacturing published between January 1, 1900 and November 3, 2021 were obtained from the Web of Science Core Collection. The citation network of the articles was analyzed for confirmation that the evolution of 3D bio-printing is reflected by tracking the key articles in the field. However, the results revealed that the major articles on the clinical application of 3D bio-printed products are located in clusters other than that of 3D bio-printers. We investigated the research trends in this field by analyzing the articles published between 2019 and 2021 and detected various basic technologies constituting tissue engineering, including microfluidics and scaffolds such as electrospinning and conductive polymers. The results suggested that the research trend of technologies required for product development and future clinical applications of the product are sometimes detected independently by bibliographic citation network analysis, particularly for interdisciplinary fields.

CONCLUSION

This method can be applied to the horizon scanning of an interdisciplinary field. However, identifying basic technologies of the targeted field and following the progress of research and the integration process of each component of technology are critical.

The effects of atomic percentage and size of Zinc nanoparticles, and atomic porosity on thermal and mechanical properties of reinforced calcium phosphate cement by molecular dynamics simulation

This study used the molecular dynamics (MD) simulation method to assess the effects of different percentages of NPs, sizes, and percentages of porosity on reinforced cement thermal behavior (TB) and mechanical behavior (MB) of samples. The temperature and kinetic energy (KE) converged to 300 K and 35.42 eV after 10 ns, which indicated the thermodynamic equilibrium and the atomic stability in the structures. Increasing the NPs percentage from 1% to 3% increased the maximum temperature from 1364 to 1405 K. By further increasing it to 5%, it was reduced to 1361 K. As the radius of Zn NPs increased to 16 Å, the ultimate strength (US) and Young's Modulus (YM) increased from 1.07 to 0.19 MPa to 1.2 and 0.22 MPa. The increase in the NPs' radius to 16 Å caused an increase in the maximum temperature from 1405 to 1455 K, maintaining atomic stability. As the porosity increased from 1% to 5%, the US and YM reduced from 0.91 to 0.17 MPa to 0.81 and 0.15 MPa. As the porosity increased from 1% to 5%, the maximum temperature was reduced from 1400 K to 1384 K. According to the results, Zn NPs' percentage and size effectively improved the MB of the final cement.

A Review on the Role of Wollastonite Biomaterial in Bone Tissue Engineering

Millions of people around the world have bone-tissue defects. Autologous and allogeneic bone grafting are frequent therapeutic techniques; however, none has produced the best therapeutic results. This has inspired researchers to investigate novel bone-regeneration technologies. In recent years, the development of bone tissue engineering (BTE) scaffolds has been at the forefront of this discipline. Due to their limitless supply and lack of disease transmission, engineered bone tissue has been advanced for the repair and reconstruction of bone deformities. Bone tissue is a highly vascularized, dynamic tissue that constantly remodels during an individual's lifetime. Bone tissue engineering is aimed at stimulating the creation of new, functional bone by combining biomaterials, cells, and factor treatment synergistically. This article provides a review of wollastonite's biomaterial application in bone tissue engineering. This work includes an explanation of wollastonite minerals including mining, raw materials for the synthesis of artificial wollastonite with various methods, its biocompatibility, and biomedical applications. Future perspectives are also addressed, along with topics like bone tissue engineering, the qualities optimal bone scaffolds must have, and the way a scaffold is designed can have a big impact on how the body reacts.

Taguchi grey relational optimization of sol-gel derived hydroxyapatite from a novel mix of two natural biowastes for biomedical applications

The comparative study of natural hydroxyapatite (NHAp) from bovine (B) and catfish (C) bones using different fabrication parameters has been extensively researched through traditional investigation. However, the quantitative effect optimization of a novel mix proportion of hydroxyapatite from these bones, and fabrication parameters have not been examined. Hence, this study presents the effect of the powder mixture, compaction pressure, and sintering temperature (as production parameters) on the experimental mechanical properties of naturally derived HAp. The bovine bone and catfish bone biowastes were used in mixed proportions to produce hydroxyapatite via the sol-gel synthesis protocol. The powders were calcined separately at 900 °C to convert the deproteinized biowaste. Next, the powders were combined chemically (sol-gel) in the appropriate ratios (i.e. 45 g of B: 15 g of C (B75/C25), 30 g of B: 30 g of C (B50/C50), and 15 g of B; 45 g of C (B25/C75)). Taguchi design supported by grey relational analysis was employed with an L9 orthogonal array. The Minitab 16 software was employed to analyze the Taguchi design. The result revealed an inconsistency in the powder mixture as the optimum state for individual mechanical properties, but the grey relational analysis (GRA) showed better mechanical properties with a powder mix of B50/C50, 500 Pa compaction pressure, and 900 °C sintering temperature. The obtained result further showed that the novel mix of these powders is a good and promising material for high-strength biomedical applications, having a contribution of 97.79% on hardness and 94.39% on compressive strength of HAp. The obtained experimental grey relational grade of 0.7958 is within the 95% confidence interval, according to confirmation analysis (CA). The optimum powder parameter was examined using X-ray diffraction (XRD), and its structure, size, and elemental makeup were examined using scanning electron microscopy (SEM) and energy dispersive spectroscopy (EDS) analysis. The sample had a higher degree of crystallinity and mean crystallite size of 80.42% and 27.3 nm, respectively. The SEM images showed big, gritty grains that are not tightly packed.

Silk fibroin hydrogels induced and reinforced by acidic calcium phosphate - A simple way of producing bioactive and drug-loadable composites for biomedical applications

Silk fibroin (SF) hydrogels have attracted extensive interest in biomedical applications due to their biocompatibility and wide availability. However, their generally poor mechanical properties limit their utility. Here, injectable, ready-to-use SF-based composites, simultaneously induced and reinforced by acidic calcium phosphates, were prepared via a dual-paste system requiring no complex chemical/physical treatment. The composite was formed by mixing a monocalcium phosphate monohydrate paste with a β-tricalcium phosphate/SF paste. The conformational transition of SF in an acidic environment forms continuous networks, and the acidic calcium phosphate, brushite and monetite, formed simultaneously in the networks during mixing. The composites displayed a partly elastomeric compression behavior, with mechanical properties increasing with an increasing calcium phosphate and β-sheet content at the lower calcium phosphate contents evaluated (22.2-36.4 wt%). While the stiffness was still relatively low, the materials presented a high elasticity and ductility, and no failure at stresses in the range of failure stresses of trabecular bone. Furthermore, the calcium phosphate confers bioactivity to the material, and the composites with a promising in vitro cell response also showed potential as drug vehicles, using vancomycin as a model drug. These dual-paste systems exhibit potential utility in biomedical applications, such as bone void fillers and drug vehicles.

Synthesis techniques, characterization and mechanical properties of natural derived hydroxyapatite scaffolds for bone implants: a review

Hydroxyapatite (HAp) with good mechanical properties is a promising material meant for a number of useful bids in dentistry and orthopedic for biomedical engineering applications for drug delivery, bone defect fillers, bone cements, etc. In this paper, a comprehensive review has been done, by reviewing different literatures related to synthesis techniques, mechanical properties and property testing, method of calcination and characterization of hydroxyapatite which are product of catfish and bovine bones. The discussion is in relations of the obligatory features vital to attain the best properties for the envisioned bid of bone graft. The process approaches that are capable of fabricating the essential microstructure and the ways to advance the mechanical properties of natural mined HAp are reviewed. The standard values for tensile strength were found to be within the range of 40–300 MPa, compressive strength was 400–900 MPa, while Elastic modulus was 80–120 GPa and fracture toughness was 0.6–1 MPa m1/2 (Ramesh et al. in Ceram Int 44(9):10525–10530, 2018; Landi et al. in J Eur Ceram Soc 20(14–15):2377–2387, 2000; Munar et al. in Dent Mater J 25(1):51–58, 2006). Also, the porosity range was 70–85% (Yang et al. in Am Ceram Soc Bull 89(2):24–32, 2010), density is 3.16 g/cm3 and relative density is 95–99.5% (Ramesh et al. 2018; Landi et al. 2000; Munar et al. 2006). The literature revealed that CaP ratio varies in relation to the source and sintering temperature. For example, for bovine bone, a CaP ratio of 1.7 (Mezahi et al. in J Therm Anal Calorim 95(1):21–29, 2009) and 1.65 (Barakat et al. in J Mater Process Technol 209(7):3408–3415, 2009) was obtained at 1100 °C and 750 °C respectively. Basic understanding on the effect of adding foreign material as a strengthening agent to the mechanical properties of HAp is ground factor for the development of new biomaterial (Natural hydroxyapatite, NHAp). Therefore, it is inferred that upon careful combination of main parameters such as compaction pressures, sintering temperatures, and sintering dwell times for production natural HAp (NHAp), mechanical properties can be enhanced.

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Investigation of the mechanical properties of a bony scaffold for comminuted distal radial fractures: Addition of akermanite nanoparticles and using a freeze-drying technique

One of the methods of repairing the damaged bone is the fabrication of porous scaffold using synergic methods like three-dimensional (3D) printing and freeze-drying technology. These techniques improve the damaged and fracture parts rapidly for better healing bone lesions using bioactive ceramic and polymer. This research, due to the need to increase the mechanical strength of 3D bone scaffolds for better mechanical performance. Akermanite bioceramic as a bioactive and calcium silicate bioceramic has been used besides the polymeric component. In this study, the porous scaffolds were designed using solid work with an appropriate porosity with a Gyroid shape. The prepared Gyroid scaffold was printed using a 3D printing machine with Electroconductive Polylactic Acid (EC-PLA) and then coated with a polymeric solution containing various amounts of akermanite bioceramic as reinforcement. The mechanical and biological properties were investigated according to the standard test. The mechanical properties of the porous-coated scaffold showed stress tolerance up to 30 MPa. The maximum strain obtained was 0.0008, the maximum stress was 32 MPa and the maximum displacement was 0.006 mm. Another problem of bone implants is the impossibility of controlling bone cancer and tumor size. To solve this problem, an electroconductive filament containing Magnetic Nanoparticles (MNPs) is used to release heat and control cancer cells. The mechanical feature of the porous scaffold containing 10 wt% akermanite was obtained as the highest stress tolerance of about 32 MPa with 46% porosity. Regarding the components and prepare the bony scaffold, the MNPs release heat when insert into the magnetic field and control the tumor size which helps the treatment of cancer. In general, it can be concluded that the produced porous scaffold using 3D printing and freeze-drying technology can be used to replace broken bones with the 3D printed EC-PLA coated with 10 wt% akermanite bioceramic with sufficient mechanical and biological behavior for the orthopedic application.

Enhancing ZnO-NP Antibacterial and Osteogenesis Properties in Orthopedic Applications: A Review

Prosthesis-associated infections and aseptic loosening are major causes of implant failure. There is an urgent need to improve the antibacterial ability and osseointegration of orthopedic implants. Zinc oxide nanoparticles (ZnO-NPs) are a common type of zinc-containing metal oxide nanoparticles that have been widely studied in many fields, such as food packaging, pollution treatment, and biomedicine. The ZnO-NPs have low toxicity and good biological functions, as well as antibacterial, anticancer, and osteogenic capabilities. Furthermore, ZnO-NPs can be easily obtained through various methods. Among them, green preparation methods can improve the bioactivity of ZnO-NPs and strengthen their potential application in the biological field. This review discusses the antibacterial abilities of ZnO-NPs, including mechanisms and influencing factors. The toxicity and shortcomings of anticancer applications are summarized. Furthermore, osteogenic mechanisms and synergy with other materials are introduced. Green preparation methods are also briefly reviewed.