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Blend nanofibers composed of synthetic and natural polymers with carbon nanomaterial, have a great potential for bone tissue engineering. In this study, the electrospun nanocomposite scaffolds based on polyhydroxybutyrate(PHB)-Starch-multiwalled carbon nanotubes (MWCNTs) were fabricated with different concentrations of MWCNTs including 0.5, 0.75 and 1 wt%. The synthesized scaffolds were characterized in terms of morphology, porosity, thermal and mechanical properties, biodegradation, bioactivity, and cell behavior. The effect of the developed structures on MG63 cells was determined by real-time PCR quantification of collagen type I, osteocalcin, osteopontin and osteonectin genes. Our results showed that the scaffold containing 1 wt% MWCNTs presented the lowest fiber diameter (124 ± 44 nm) with a porosity percentage above 80 % and the highest tensile strength (24.37 ± 0.22 MPa). The addition of MWCNTs has a positive effect on surface roughness and hydrophilicity. The formation of calcium phosphate sediments on the surface of the scaffolds after immersion in SBF is observed by SEM and verified by EDS and XRD analysis.MG63 cells were well cultured on the scaffold containing MWCNTs and presented more cell viability, ALP secretion, calcium deposition and gene expression compared to the scaffolds without MWCNTs. The PHB-starch-1wt.%MWCNTs scaffold can be considerable for studies of supplemental bone tissue engineering applications. [ABSTRACT FROM AUTHOR]

Efficient design for bone tissue engineering requires an understanding of the appropriate selection of biomimetic natural or synthetic materials and scalable fabrication technologies. In this research, poly (3-hydroxybutyrate) (PHB) and starch (5-15 wt%) as biological macromolecules were used to fabricate novel biomimetic scaffolds by electrospinning method. SEM results of electrospun scaffolds revealed bead-free nanofibers and three-dimensional homogenous structures with highly interconnected pores. Results of FTIR and Raman demonstrated that there were hydrogen bonds between the two polymers. The tensile strength of scaffolds was significantly improved by adding starch up to 10 wt%, from 3.05 to 15.54 MPa. In vitro degradation and hydrophilicity of the scaffolds were improved with the presence of starch. The viability and proliferation of MG-63 cells and alkaline phosphatase (ALP) activity were remarkably increased in the PHB-starch scaffolds compared to the PHB and control samples. The mineralization and calcium deposition of MG-63 cells were confirmed by alizarin red staining. It is concluded that PHB/starch electrospun scaffold could be a good candidate for bone tissue engineering applications. • PHB-starch scaffolds were made using electrospinning method. • The hydrophilicity and biodegradation of the scaffolds were increased by adding starch. • Tensile strength of the scaffolds was increased in the presence of 10 wt% starch. • Cell viability was significantly increased by adding starch to the scaffolds. • PHB-starch electrospun scaffolds could create a favorable microenvironment for bone tissue engineering applications. [ABSTRACT FROM AUTHOR]

Nowadays, the utilization of 3D printing has become common in the construction of composite scaffolds. In this research, the co-precipitation method was applied to synthesize pure strontium hexaferrite oxide (SrFe 12 O 19) and magnesium-doped strontium hexaferrite oxide nanoparticles (Mg–SrFe 12 O 19). The synthesized SrFe 12 O 19 nanoparticles had a spherical morphology with a mean size of 60 nm and magnetization (Ms) value of 54.38 emu/g. The Mg–SrFe 12 O 19 also had a spherical morphology with a mean particle size of 46 nm and a magnetization value of 29.89 emu/g. The produced polycaprolactone composite scaffolds containing different amounts (0, 25, 50, and 75 wt%) of reinforcement were fabricated by the 3D robocasting printing method. Based on the results of the compression test, the 25 wt% addition of the pure SrFe 12 O 19 nanoparticles to the polycaprolactone scaffold increased the compressive strength from 2.87 to 11.68 MPa compared to the 100 wt% pure polycaprolactone scaffold. Furthermore, the polycaprolactone nanocomposite scaffold containing 25 wt% Mg–SrFe 12 O 19 also increased the compressive strength compared to the pure polycaprolactone scaffold to 12.94 MPa. Therefore, the 25 wt% reinforced scaffold was chosen as the optimal sample. The contact angles of the pure polycaprolactone SrFe 12 O 19 and Mg– SrFe 12 O 19 reinforced polycaprolactone scaffolds were 77.17, 68.53, and 35.58°, respectively. The values indicate the significant effect of doping magnesium on the wettability. The degradability of the 3D-printed scaffolds containing 25 wt% of the two different reinforcements was evaluated for 28 days immersing in phosphate-buffered saline (PBS) solution. The results revealed that the degradability was higher for the Mg–SrFe 12 O 19 after 28 days compared to the composite scaffold reinforced by pure SrFe 12 O 19 reinforcement. Moreover, it was shown that the bioactivity and cell adhesion of MG63 cells for the scaffolds reinforced by Mg–SrFe 12 O 19 have increased in laboratory conditions. Based on the MTT test, it was observed that both of the scaffolds were non-toxic. The results obtained in this study, suggest that polycaprolactone nanocomposite scaffolds containing 25 wt% of Mg–SrFe 12 O 19 , made by the 3D robocasting printing method, are suitable for bone tissue engineering. [ABSTRACT FROM AUTHOR]

Nowadays, using the nanocomposite coatings on bioceramic scaffolds is a great interest for many researchers to improve the properties of these scaffolds. In this study, the effect of poly (3-hydroxybutyrate) PHB-Chitosan (Cs)/multi-walled carbon nanotubes (MWCNTs) nanocomposite coating deposited on nano-bioglass (nBG)-titania (nTiO 2) scaffolds fabricated by foam replication method was investigated. Structural analyses such as XRD and FT-IR confirmed the presence of PHB, Cs and MWCNTs in the coated scaffolds. The results of SEM and porosity measurement showed that even with 1 wt% MWCNTs, scaffolds have a high percentage of interconnected porosity. The compressive strength of the scaffolds coated with PHB-Cs/MWCNTs (1 wt%) was increased up to 30 folds compared to nBG/nTiO 2 scaffold. The surface roughness of the coated scaffolds, which was determined by AFM, was increased. The nanocomposite coating caused a decrease in contact angle and retaining the negative zeta potential of the coated scaffolds. The increase in pH and degradation rate was observed in the coated scaffolds. Increasing the apatite-like formation by the presence of PHB-Cs/MWCNTs was confirmed by SEM, EDAX and XRD tests. PHB-Chitosan/MWCNTs nanocomposite coating lead to more proliferation and viability of MG-63 cells and higher secretion of alkaline phosphatase. • nBG/nTiO 2 scaffolds were made by foam replication method and coated with PHB-Cs/MWCNTs • The hydrophilicity of coated scaffold was increased • The compressive strength and surface roughness were significantly increased by the presence of MWCNTs. • Apatite-like formation was increased by the presence of PHB-Cs/MWCNTs • Proliferation, viability and ALP of MG-63 cells were significantly increased for coated scaffolds [ABSTRACT FROM AUTHOR]

Dental pulp is a highly specialized tissue that preserves teeth. It is important to maintain the capabilities of dental pulp before a pulpectomy by creating a local restoration of the dentin-pulp complex from residual dental pulp. The articles identified were selected by two reviewers based on entry and exit criteria. All relevant articles indexed in PubMed, Springer, Science Direct, and Scopus with no limitations from 1961 to 2016 were searched. Factors investigated in the selected articles included the following key words: Dentin-Pulp Complex, Regeneration, Tissue Engineering, Scaffold, Stem Cell, and Growth Factors. Of the 233 abstracts retrieved, the papers which were selected had evaluated the clinical aspects of the application of dentin-pulp regeneration. Generally, this study has introduced a new approach to provoke the regeneration of the dentin-pulp complex after a pulpectomy, so that exogenous growth factors and the scaffold are able to induce cells and blood vessels from the residual dental pulp in the tooth root canal. This study further presents a new strategy for local regeneration therapy of the dentin-pulp complex. This review summarizes the current knowledge of the potential beneficial effects derived from the interaction of dental materials with the dentin-pulp complex as well as potential future developments in this exciting field. [ABSTRACT FROM AUTHOR]

The tissue engineering scaffolds requires efficient combination of materials, appropriate method of preparation, and precise characterization of final product. In this study, the optimal electrospinning process conditions of polyhydroxybutyrate (PHB) were investigated by Taguchi design. Then, the initial PHB solution characteristics in the presence of lignin were optimized and then electro-spun. In this regard, the uniformity of electro-spun nanofibers, observed by SEM, confirmed that 9 w/v % is the optimum concentration of PHB in Trifluoro acetic acid. Addition of 6 wt% of lignin to PHB, could alleviate both the brittleness and hydrophobicity of PHB, as DSC, XRD, and WCA results indicated decrement in crystallinity (from 46 to 39 %), crystal size (from 21.8 to 15.2 nm), and WCA (from 118 to 73°). On the other hand, FESEM results represented diameter reduction from 1318 ± 202.07 to 442 ± 111.04 nm, and transformation of nanofiber physical structure from ribbon-like to cylindrical fiber by adding lignin. In addition, the mechanical properties of PHB including elongation at break, toughness, young modulus, and tensile strength were also improved (up to twice) by adding lignin. Ultimately, reviewing the outputs of degradation, bioactivity, MG63 cell viability, proliferation, mineralization, and antioxidant activity confirm that PHB/lignin electrospun scaffold has potential application in tissue engineering. [Display omitted] [ABSTRACT FROM AUTHOR]

One of the most popular types of bone cements is polymethylmethacrylate (PMMA). The properties of this bone cement have attracted many researchers effort to modify its properties. In this study, after preparation of chitosan (Cs) powder and Cs/graphene oxide (GO) nanocomposite powder, they were added homogeneously to the PMMA bone cement with different percentages. The results showed that the addition of 25 wt% of Cs/GO nanocomposite powder to the PMMA bone cement cause to increase the compressive strength by 16.2%, the compressive modulus by 69.1% and the bending strength by 24.0%. The obtained results showed that by adding Cs/GO nanocomposite powder to the PMMA bone cement, setting time and injectability were increased, maximum temperature was decreased and apatite-like deposition was increased after 4 weeks of incubation in SBF solution. The results of MG-63 cell culture confirmed the improvement of cell viability, growth and cell adhesion for 25 wt% PMMA-Cs/GO composite bone cement. Therefore, it can be concluded that 25 wt% PMMA-Cs/GO composite bone cement with improved mechanical, physical and biological properties can be a good replacement for common commercial bone cements in orthopedic applications. Unlabelled Image • Composite bone cement including of Cs/GO nanocomposite and PMMA is prepared • Addition of Cs/GO nanocomposite powder to the PMMA bone cement, increased injectability and setting time, significantly • Addition of Cs/GO nanocomposite powder to the PMMA bone cement, decreased polymerization temperature • Addition of Cs/GO nanocomposite powder to the PMMA bone cement, improved mechanical properties, significantly • Bioactivity and cellular behavior of composite bone cement improved, significantly [ABSTRACT FROM AUTHOR]

Abstract: A novel in situ synthesis is presented of a hydroxyapatite composite with the mesoporous silicate MCM-48 with potential applications as a drug delivery agent. The structure and properties of this nanocomposite, investigated by a number of techniques including XRD, SEM and TEM, show the intergrowth of the hydroxyapatite particles with the silica structure. The bioactivity of the new material was determined by measuring the decrease in the calcium ion concentration of simulated body fluid (SBF) after soaking the nanocomposite, while the uptake of ibuprofen on MCM-48 and MCM-48/HAp composite from ethanol was monitored by UV spectroscopy at 222nm which was also used to monitor the release of ibuprofen into SBF, MTT assay was used to assess effect of the sample on MG68 cell live proliferation. The results confirm the successful synthesis of a MCM-48/hydroxyapatite nanocomposite and its potential biomedical applications as a bioactive ceramic and as a drug delivery agent with a higher rate of ibuprofen release compared to MCM-48. [Copyright &y& Elsevier]

Today, the integration of medical and engineering principles for producing biological replacements has attracted much attention. Tissue engineering is an interdisciplinary field introduced for recovery, preservation, and improvement of tissues' function. During the process of reproduction, scaffolds with the support of cells and biological materials and growth factors underlie the effective regeneration of the target tissue. Among the numerous methods, the electrospinning method has the great ability to mimic the extracellular matrix by creating a network of polymer fibers with a high surface area at the nanoscale in order to provide more binding sites for cells. Considering the capabilities and limitations of different polymers, the use of ceramics as a reinforcement phase is a promising approach. Over the past few decades, electrospun scaffolds have been developed by adding different ceramics in terms of their nature, bioinert, bioactive, and biodegradable properties. The main results are related to enhancing the mechanical properties and biological behavior of the polymeric scaffolds after the incorporation of ceramics. Enhanced hydrophilicity, antibacterial and antioxidant properties are other aspects caused by chemical interactions of ceramics and polymers. In this review, the effect of adding inorganic ceramic structures incorporated into polymeric electrospun scaffolds is discussed by highlighting the most recent studies in tissue engineering applications. [Display omitted] [ABSTRACT FROM AUTHOR]

This study introduces an innovative co-delivery approach using the MCM-co-polymerized nanosystem, integrating chitosan and polyethylene glycol, and targeted by the MUC-1 aptamer (MCM@CS@PEG-APT). This system enables simultaneous delivery of the GFP plasmid and doxorubicin (DOX). The synthesis of the nanosystem was thoroughly characterized at each step, including FTIR, XRD, BET, DLS, FE-SEM, and HRTEM analyses. The impact of individual polymers (chitosan and PEG) on payload retardation was compared to the co-polymerized MCM@CS@PEG conjugation. Furthermore, the DOX release mechanism was investigated using various kinetic models. The nanosystem's potential for delivering GFP plasmid and DOX separately and simultaneously was assessed through fluorescence microscopy and flow cytometry. The co-polymerized nanosystem exhibited superior payload entrapment (1:100 ratio of Plasmid:NPs) compared to separately polymer-coated counterparts (1:640 ratio of Plasmid:NPs). Besides, the presence of pH-sensitive chitosan creates a smart nanosystem for efficient DOX and GFP plasmid delivery into tumor cells, along with a Higuchi model pattern for drug release. Toxicity assessments against breast tumor cells also indicated reduced off-target effects compared to pure DOX, introducing it as a promising candidate for targeted cancer therapy. Cellular uptake findings demonstrated the nanosystem's ability to deliver GFP plasmid and DOX separately into MCF-7 cells, with rates of 32% and 98%, respectively. Flow cytometry results confirmed efficient co-delivery, with 42.7% of cells showing the presence of both GFP-plasmid and DOX, while 52.2% exclusively contained DOX. Overall, our study explores the co-delivery potential of the MCM@CS@PEG-APT nanosystem in breast cancer therapy. This system's ability to co-deliver multiple agents preciselyopens new avenues for targeted therapeutic strategies. [Display omitted] • Mesoporous silica@chitosan@Polyethylene glycol-MUC1 aptamer as a multifaceted type of smart nanosystem was fabricated. • The fabricated nanosystem was employed for co-delivery of two payloads, including GFP-plasmid and doxorubicin (DOX). • The co-polymerized configuration of the nanosystem exhibited a remarkable reduction in payload retardation compared to others. • The MCM@CS@PEG-APT indicated the selective uptake of DOX (98%) as well as GFP (31%) by MUC-1-positive tumor cells nanosystem. • The co-delivery efficiency of the nanosystem is evident, with 42.7% of cells exhibiting the presence of both GFP-plasmid and DOX. [ABSTRACT FROM AUTHOR]

• PHB-Keratin scaffold made using electrospinning method. • The hydrophilicity of the scaffolds was increased by adding Keratin. • Biodegradation of the scaffolds was increased in presence of Keratin. • Tensile strength of the scaffolds were increased in presence of 10 wt% Keratin. • ALP of MG-63 cells were significantly increased by adding Keratin to the scaffolds. Proper selection of materials and methods of construction are important factors in scaffolding in tissue engineering. In this research, a novel biomimetic scaffold containing poly (3-hydroxybutyrate) (PHB) and keratin (5–15 wt. %) was prepared by the electrospinning method. The results showed that all electrospun scaffolds have 3D structures with high interconnected porosity and hydrophilicity. FTIR, Raman and 1H-NMR indicated the presence of keratin in electrospun scaffolds and the hydrogen bond between the two polymers. Crystallinity of the scaffolds, which was measured by DSC and verified by XRD, demonstrated that the presence of keratin reduces the crystallinity and improves the thermal behavior of scaffolds. According to the mechanical evaluation, by adding up to 10 wt. % of keratin, tensile strength of scaffolds is increased from 2.29 to 2.92 Mpa, respectively. In vitro degradation of the scaffolds was increased by the presence of keratin. Cell culture of the MG-63 revealed that viability, proliferation and ALP secretion are significantly increased by adding keratin to the scaffolds. The proper properties of PHB-10 k electrospun scaffold made it a promising alternative biomaterial for bone tissue engineering applications. [ABSTRACT FROM AUTHOR]

Ceramic-magnetic nanoparticles (CMNPs) are attracting attention due to their various applications, especially in biomedical industries. Among them, spinel ferrite CMNPs have received considerable deliberations among different spinel metal oxides due to their fascinating characteristics. Spinel ferrite CMNPs are used for enhancement of the applicability of CMNPs without affecting the intrinsic advantages of iron oxide CMNPs. Spinel ferrites with doping agents have useful electrical and magnetic properties in various fields. Moreover, the replacement of metallic atoms in ferrites is promising to manipulate physical characteristics and improve their performance. Among different spinel ferrites, CoFe 2 O 4 nanoparticles are the most investigated CMNPs. Furthermore, they are used as permanent magnets, magnetic recorders in high-density and micro-wave devices, and magnetic fluids. This study reviews the CoFe 2 O 4 nanoparticles doped with various elements and their applications in various fields. [ABSTRACT FROM AUTHOR]

Nano-micro scaffolds are developed for long-term healing tissue engineering like cartilage. The poly 3-hydroxybutyrate (P3HB)-chitosan/silk and P3HB-chitosan-1 wt% multi-walled carbon nanotubes functionalized by COOH (MWNTs)/silk nano-micro scaffolds are fabricated through electrospinning the solution on a knitted silk which is saturated (S) or unsaturated (U) with P3HB as a mediator to enhance the interaction at nano/microinterface. Consuming MWNTs lead to a decrease in fiber diameter, while an increase in specific surface area, tensile strength and bioactivity properties. The saturation condition as well as MWNTs leads to intensification in the hydrophilicity properties. The nanolayer in all scaffolds lead to an increase in tensile strength in comparison with the pure knitted silk. The scaffold containing MWNTs showed slower degradation rate. MWNTs beside the chitosan and silk provide an appropriate environment for attachment and growth of chondrocytes. The P3HB-chitosan-MWNTs/silk (S) nano-microscaffold can be appropriate for a long-term tissue engineering application like cartilage. Unlabelled Image • Nano-micro scaffolds are fabricated through electrospinning the solution on a knitted silk. • Presence of MWNTs leads to an increase in specific surface area, hydrophilicity, tensile strength and bioactivity. • The scaffold containing MWNTs showed optimized degradation rate in nano and micro phase. • Presence of nano layer in all scaffolds led to an increase in tensile strength. • The nano-micro scaffolds provide an appropriate environment for chondrocytes viability. [ABSTRACT FROM AUTHOR]

• Porous polyurethane foam was prepared by solvent casting/salt leaching technique. • The PU foam was coated with the water extract of propolis (PU/WEP). • PU/WEP exhibited good antibacterial activity against E. coli and S. aureus. • PU/WEP showed appropriate cellular biocompatibility. • PU/WEP could significantly accelerate the wound healing process in vivo. Wound dressings with antimicrobial and wound healing accelerating properties are emerging as valuable options to prevent wound infection and improve the wound healing process. In this study, high porous polyurethane (PU) foams were successfully prepared using salt leaching/solvent casting method and were coated with propolis as a well-known anti-bacterial agent. The wound dressings were subjected to detail analyzes using electron microscopy, reflectance Fourier transform infrared spectroscopy, mechanical properties, contact angle measurement, ratio swelling, porosity measurement, and in vitro and in vivo evaluations. The prepared wound dressings had high porosity (more than 80%) with homogeneous pore structure and sufficient interconnectivity. The increase of propolis concentration (10%–30%) caused tensile strength decrease (5.26 ± 0.40–2.99 ± 0.11 MPa), elongation at break increase (372 ± 12–434 ± 22%), contact angle decrease (114.52 ± 2.31° to 35.53 ± 1.65°), water absorption decreased (243 ± 15–207 ± 14%) and enhancement of the antibacterial activity against Escherichia coli and Staphylococcus aureus. The propolis coated wound dressing exhibited significant enhancement of in vitro cellular compatibility and in vivo wound healing which had direct relative with coated propolis concentration. Therefore, propolis-coated polyurethane wound dressing can be an appropriate candidate for more pre-clinical investigations. [ABSTRACT FROM AUTHOR]

Three-dimensional (3D) printing technology has become an advanced approach for fabricating patient-specific scaffolds with complex geometric shapes to replace damaged or diseased tissue. Herein, polylactic acid (PLA)-Baghdadite (Bgh) scaffold were made through the fused deposition modeling (FDM) 3D printing method and subjected to alkaline treatment. Following fabrication, the scaffolds were coated with either chitosan (Cs)-vascular endothelial growth factor (VEGF) or lyophilized Cs-VEGF known as PLA-Bgh/Cs-VEGF and PLA-Bgh/L.(Cs-VEGF), respectively. Based on the results, it was found that the coated scaffolds had higher porosity, compressive strength and elastic modulus than PLA and PLA-Bgh samples. Also, the osteogenic differentiation potential of scaffolds following culture with rat bone marrow-derived mesenchymal stem cells (rMSCs) was evaluated through crystal violet and Alizarin-red staining, alkaline phosphatase (ALP) activity and calcium content assays, osteocalcin measurements, and gene expression analysis. The release of VEGF from the coated scaffolds was assessed and also the angiogenic potential of scaffolds was evaluated. The sum of results presented in the current study strongly suggests that the PLA-Bgh/L.(Cs-VEGF) scaffold can be a proper candidate for bone healing applications. [Display omitted] [ABSTRACT FROM AUTHOR]