Modulating stability and mechanical properties of silica–gelatin hybrid by incorporating epoxy‐terminated polydimethylsiloxane oligomer

Silica‐gelatin hybrids, particularly GT‐G hybrids prepared by crosslinking gelatin (G) with γ‐glycidoxypropyltrimethoxysilane (GT), have attracted much attention in tissue engineering for diverse applications in hard or soft tissue regeneration; however, scaffolds with tunable properties are needed to meet specific requirements. In this work, a silica‐gelatin hybrid (ES/GT‐G) was synthesized by incorporating epoxy‐terminated polydimethylsiloxane oligomer (ES) to modulate the properties of GT‐G hybrid. The ES/GT‐G hybrid sponge presented a 3D network structure with porosity 86.4% ± 0.9%, determined by the liquid displacement method, and average pore size 340 ± 36 μm, determined by SEM observation. Compared with GT‐G hybrid material, the prepared ES/GT‐G hybrid wet film showed a decrease of tensile strength from 2.79 ± 0.04 MPa to 1.87 ± 0.12 MPa, with an increase of elongation at break from 19.96 ± 0.66% to 29.86 ± 0.87%, and the ES/GT‐G hybrid sponge exhibited a decline of compressive yield strength from 1.21 ± 0.04 MPa to 0.72 ± 0.06 MPa, based on the tensile and compression tests respectively. The introduction of ES enhanced the thermal denaturing temperature of GT‐G by 5°C as determined by a DSC study, and increased in vitro biodegradation slightly, without significantly changing surface wettability and swelling behavior. These findings suggest that silica‐gelatin hybrids with tunable properties are promising for applications from hard to soft tissue regeneration. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016 , 133, 43059.     

Porous hydroxyapatite‐bioactive glass hybrid scaffolds fabricated via ceramic honeycomb extrusion

The successful fabrication of hydroxyapatite‐bioactive glass scaffolds using honeycomb extrusion is presented herein. Hydroxyapatite was combined with either 10 wt% stoichiometric Bioglass^® (BG1), calcium‐excess Bioglass^® (BG2) or canasite (CAN). For all composite materials, glass‐induced partial phase transformation of the HA into the mechanically weaker β‐tricalcium phosphate (TCP) occurred but XRD data demonstrated that BG2 exhibited a lower volume fraction of TCP than BG1. Consequently, the maximum compressive strength observed for BG1 and BG2 were 30.3 ± 3.9 and 56.7 ± 6.9 MPa, respectively, for specimens sintered at 1300°C. CAN scaffolds, in contrast, collapsed when handled when sintered below 1300°C, and thus failed. The microstructure illustrated a morphology similar to that of BG1 sintered at 1200°C, and hence a comparable compressive strength (11.4 ± 3.1 MPa). The results highlight the great potential offered by honeycomb extrusion for fabricating high‐strength porous scaffolds. The compressive strengths exceed that of commercial scaffolds, and biological tests revealed an increase in cell viability over 7 days for all hybrid scaffolds. Thus it is expected that the incorporation of 10 wt% bioactive glass will provide the added advantage of enhanced bioactivity in concert with improved mechanical stability.     

Facile production of porous bioactive glass scaffolds by the foam replica technique combined with sol–gel/electrophoretic deposition

3D porous bioactive glass (BG) scaffolds were fabricated by the foam replication technique combining sol–gel and electrophoretic deposition (EPD) processes. A special EPD set-up was built to optimize the scaffolds fabrication, which results in the rapid production of BG-based scaffolds in comparison to the traditional time-consuming foam replication technique normally used for the same kind of BG scaffolds. The influences of parameters related to the BG sol (aging time) as well as to the electrically driven process (deposition voltage) were studied and discussed in terms of the final scaffolds microstructure. Bioactivity of the samples, in terms of hydroxycarbonate apatite (HCA) formation in simulated body fluid (SBF), was determined after 1 day of immersion in SBF, confirming the suitability of the new scaffolds for bone regeneration applications.     

Fabrication and characterization of chitosan/PVA with hydroxyapatite biocomposite nanoscaffolds

Nanofibrous biocomposite scaffolds of chitosan (CS), PVA, and hydroxyapatite (HA) were prepared by electrospinning. The scaffolds were characterized by FTIR, SEM, TEM, and XRD techniques. Tensile testing was used for the characterization of mechanical properties. Mouse fibroblasts (L929) attachment and proliferation on the nanofibrous scaffold were investigated by MTT assay and SEM observation. FTIR, TEM, and XRD results showed the presence of nanoHA in the scaffolds. The scaffolds have porous nanofibrous morphology with random fibers in the range of 100–700 nm diameters. The CS/PVA (90/10) fibrous matrix (without HA) showed a tensile strength of 3.1 ± 0.2 MPa and a tensile modulus 10 ± 1 MPa with a strain at failure of 21.1 ± 0.6%. Increase the content of HA up to 2% increased the ultimate tensile strength and tensile modulus, but further increase HA up to 5–10% caused the decrease of tensile strength and tensile modulus. The attachment and growth of mouse fibroblast was on the surface of nanofibrous structure, and cells' morphology characteristics and viability were unaffected. A combination of nanofibrous CS/PVA and HA that mimics the nanoscale features of the extra cellular matrix could be promising for application as scaffolds for tissue regeneration, especially in low or nonload bearing areas. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2008     

Electrospun polylactide/silk fibroin–gelatin composite tubular scaffolds for small‐diameter tissue engineering blood vessels

Many synthetic scaffolds have been used as vascular substitutes for clinical use. However, many of these scaffolds may not show suitable properties when they are exposed to physiologic vascular environments, and they may fail eventually because of some unexpected conditions. Electrospinning technology offers the potential for controlling the composition, structure, and mechanical properties of scaffolds. In this study, a tubular scaffold (inner diameter = 4.5 mm) composed of a polylactide (PLA) fiber outside layer and a silk fibroin (SF)–gelatin fiber inner layer (PLA/SF–gelatin) was fabricated by electrospinning. The morphological, biomechanical, and biological properties of the composite scaffold were examined. The PLA/SF–gelatin composite tubular scaffold possessed a porous structure; the porosity of the scaffold reached 82 ± 2%. The composite scaffold achieved the appropriate breaking strength (1.28 ± 0.21 MPa) and adequate pliability (elasticity up to 41.11 ± 2.17% strain) and possessed a fine suture retention strength (1.07 ± 0.07 N). The burst pressure of the composite scaffold was 111.4 ± 2.6 kPa, which was much higher than the native vessels. A mitochondrial metabolic assay and scanning electron microscopy observations indicated that both 3T3 mouse fibroblasts and human umbilical vein endothelial cells grew and proliferated well on the composite scaffold in vitro after they were cultured for some days. The PLA/SF–gelatin composite tubular scaffolds presented appropriate characteristics to be considered as candidate scaffolds for blood vessel tissue engineering. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009     

Electrospun microporous gelatin–polycaprolactone blend tubular scaffold as a potential vascular biomaterial

The work reported involved the fabrication of an electrospun tubular conduit of a gelatin and polycaprolactone (PCL) blend as an adventitia‐equivalent construct. Gelatin was included as the matrix for increased biocompatibility with the addition of PCL for durability. This is contrary to most of the literature available for biomaterials based on blends of gelatin and PCL where PCL is the major matrix. The work includes the assiduous selection of key electrospinning parameters to obtain smooth bead‐free fibres with a narrow distribution of pore size and fibre diameter. Few reports elucidate the optimization of all electrospinning parameters to fabricate tubular conduits with a focus on obtaining homogeneous pores and fibres. This stepwise investigation would be unique for the fabrication of gelatin–PCL electrospun tubular constructs. The fabricated microfibrous gelatin–PCL constructs had pores of size ca 50–100 μm reportedly conducive for cell infiltration. The measured value of surface roughness of 57.99 ± 17.4 nm is reported to be favourable for protein adhesion and cell adhesion. The elastic modulus was observed to be similar to that of the tunica adventitia of the native artery. Preliminary in vitro and in vivo biocompatibility tests suggest safe applicability as a biomaterial. Minimal cytotoxicity was observed using MTT assay. Subcutaneous implantation of the scaffold demonstrated acute inflammation which decreased by day 15. The findings of this study could enable the fabrication of smooth bead‐free microfibrous gelatin–PCL tubular construct as viable biomaterial which can be included in a bilayer or a trilayer scaffold for vascular tissue engineering. © 2019 Society of Chemical Industry     

Nanofibrous scaffold prepared by electrospinning of poly(vinyl alcohol)/gelatin aqueous solutions

A series of nanofibrous scaffolds were prepared by electrospinning of poly(vinyl alcohol) (PVA)/gelatin aqueous solution. PVA and gelatin was dissolved in pure water and blended in full range, then being electrospun to prepared nanofibers, followed by being crosslinked with glutaraldehyde vapor and heat treatment to form nanofibrous scaffold. Field emission scanning electron microscope (FESEM) images of the nanofibers manifested that the fiber average diameters decreased from 290 to 90 nm with the increasing of gelatin. In vitro degradation rates of the nanofibers were also correlated with the composition and physical properties of electrospinning solutions. Cytocompatibility of the scaffolds was evaluated by cells morphology and MTT assay. The FESEM images revealed that NIH 3T3 fibroblasts spread and elongated actively on the scaffolds with spindle‐like and star‐type shape. The results of cell attachment and proliferation on the nanofibrous scaffolds suggested that the cytotoxicity of all samples are grade 1 or grade 0, indicating that the material had sound biosafety as biomaterials. Compared with pure PVA and gelatin scaffolds, the hybrid ones possess improved biocompatibility and controllability. These results indicate that the PVA/gelatin nanofibrous have potential as skin scaffolds or wound dressing. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011     

Nanoengineered biocomposite tricomponent polymer based matrices for bone tissue engineering

Nanoengineered biodegradable constructs based on synthetic and natural polymers enriched with hydroxyapatite (HA) nanoparticles have been found to mimic the extracellular matrix of bone tissue. The main objective of this study was to create biocomposite nanostructured scaffolds by incorporating collagen and HA nanoparticles into poly(L-lactic acid)-co-poly(?-caprolactone) by electrospinning. The fiber diameter of the composite PLCL/Col and PLCL/Col/HA fibers was smaller compared to PLCL. In vitro biocompatibility of the scaffolds studied using human fetal osteoblasts and EDX analysis showed high deposition of calcium on PLCL/Col/HA. The results shows that PLCL/Col/HA nanofibrous constructs have huge potential as substrates for bone regeneration.     

Studying the Potential Application of Electrospun Polyethylene Terephthalate/Graphene Oxide Nanofibers as Electroconductive Cardiac Patch

Nowadays, engineering‐based cardiac patches aim to accelerate cardiac regeneration in myocardial infarcted tissues. Considering the fundamental role of cardiac electrophysiology in myocardial function, this study aims to investigate graphene oxide (GO) incorporation in the polyethylene terephthalate (PET) nanofibrous scaffold, as a conductive cardiac patch. The PET/GO nanocomposites are prepared using the uniaxial nozzle and coaxial nozzle electrospinning processes and comprehensively evaluated. The morphological observation indicates a uniform beaded free morphology with an average diameter of 147 ± 38 and 253 ± 67 nm for solid and core–shell nanocomposite fibers, respectively. Addition of GO to the PET nanofibers in a concentration of 0.05 wt% remarkably increases the Young modulus of mats from 30 ± 0.03 to 60 ± 0.02 and 69 ± 0.08 MPa for solid and core–shell nanofibers, respectively. Also, the electroconductivity is improved from 0.7 × 10^?6 to 1.175 × 10^?6 and 1.3 × 10^?6 S cm^?1 for solid and core–shell nanofibers, which are in the range of cardiac electroactivity values. PET/GO substrate interestingly supports human umbilical vein endothelial cells’ spreading morphology and cardiomyocyte elongated morphology, mainly where the GO nanosheets are distributed near the surface of nanofibers. In conclusion, the core–shell electrospun PET/GO nanocomposite fibers are suggested as a potential electroactive cardiac patch to improve cardiac cell attachment and proliferation.     

Electrospinning of Poly(3‐hydroxybutyrate‐co‐3‐hydroxyvalerate) nanofibers with feature surface microstructure

The development of surface microstructure with specific features in electrospun nanofibers has attracted more and more attention in recent years. In this article, a common biological polyester, poly(3‐hydroxybutyrate‐co‐3‐hydroxyvalerate) (PHBV) was electrospinning into nanofibers with “coral‐like” surface microstructure by a conventional‐electrospinning setup. The effect of the process parameters on the microstructure in electrospun nanofibers were investigated via a series of experiments. The formation mechanism of this feature structure and cytotoxicity assays of PHBV membrane were also discussed. The water contact angle of the electrospun PHBV membrane was higher than that of the PHBV cast film due to a very‐rough fiber surface including porous beads when PHBV was electrospun from the concentration of 4 wt %. Because of special hole shape and size distribution, the physical structure of surface of PHBV electrospun fibers offered it special properties, such as specific‐surface area, hydrophilic–hydrophobic properties, adhesion properties of cells and biological substances, etc. The demonstrated method of form coral structure would contribute to the areas such as filtration, sensor, tissue engineering scaffolds, and carriers of drugs or catalysis. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013     

Evaluation of the chondrogenic differentiation of mesenchymal stem cells on hybrid biomimetic scaffolds

Hybrid materials are widely and promisingly used as scaffolds in cartilage tissue remodeling. In this study, hybrid scaffolds consist of polycaprolactone (PCL), poly(vinyl alcohol) (PVA) with/without gelatin (GEL) to mimic natural cartilage extracellular matrix (ECM) were investigated. Scaffolds were prepared by freeze drying and characterized by scanning electron microscopy and compressive mechanical testing. Biological assays of mesenchymal stem cell (MSC) cultures, 3‐(4,5‐dimethylthiazol‐2‐yl)‐2,5‐diphenyltetrazolium bromide, and dimethyl methylene blue were performed, and real‐time polymerization chain reaction analysis of the cartilage‐specific ECM gene marker expression was done. The results show an open interconnected porous structure with a compression modulus of 1.27 ± 0.04 MPa. The surface of the scaffolds showed an excellent efficiency in the adhesion and proliferation of MSCs. A significant increase in the proteoglycan content from 3.70 ± 0.96 to 5.4 ± 1.13 μg/mL was observed after 14 days in the PCL–PVA–GEL scaffolds. The expression amount of the sex‐determining region Y–Box 9 (SOX9) and collagen II (COL2) mRNA levels of the MSCs showed significant increases in SOX9 and COL2, respectively in comparison with PCL–PVA scaffold. The study revealed that the aforementioned scaffold as a blend of natural and synthetic polymers may be a promising substrate in tissue engineering for cartilage repair with MSC transplantation. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014 , 131, 40635.     

Herbally derived polymeric nanofibrous scaffolds for bone tissue regeneration

Hydroxyapatite (HA), the bone mineral and Cissus quadrangularis (CQ), a medicinal plant with osteogenic activity, are attaining increasing interest as a potential therapeutic agent for enhanced bone tissue regeneration. In the present study a synergistic effect of these two agents were analyzed by fabricating PCL‐CQ‐HA nanofibrous scaffolds by electrospinning and compared with PCL‐CQ and PCL (control) nanofibrous scaffolds. Morphology, composition, hydrophilicity, and mechanical properties of the electrospun PCL, PCL‐CQ, PCL‐CQ‐HA nanofibrous scaffolds were examined by Field emission scanning electron microscopy (FESEM), Fourier transform infrared spectroscopy (FTIR), Contact angle and Tensile tests, respectively. The response of human foetal osteoblast cells on these scaffolds were evaluated using MTS assay, alkaline phosphatase activity, alizarin red staining, and osteocalcin expression for bone tissue regeneration. While the observed cellular response to both groups of scaffolds was better than for the control PCL scaffold, the PCL‐CQ‐HA nanofibrous scaffolds provided the most favorable substrate for cell proliferation and mineralization. The results showed that PCL‐CQ‐HA nanofibrous scaffolds had appropriate surface roughness for the osteoblast adhesion, proliferation, and mineralization comparing with other scaffolds. The observed investigation of physicochemical and biological properties suggests that the CQ‐HA loaded PCL nanofibrous scaffolds serve as a potential biocomposite material for bone tissue engineering. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014 , 131, 39835.     

Dual drug spatiotemporal release from functional gradient scaffolds prepared using 3D bioprinting and electrospinning

Functional gradient scaffolds play an important role in osteochondral tissue engineering because they can meet the essential requirement for a gradual transition of both physical and chemical properties in osteochondral tissue regeneration. There is a requirement for 3D composite osteochondral regeneration scaffolds with multiscale structures that are capable of controlling release of multiple biomolecules. To this end, this article describes a 3D bioprinting platform integrated forming system designed to produce various drug‐loaded scaffolds. A novel scaffold was fabricated by the self‐developed 3D bioprinting platform combining extrusion deposition with multi‐nozzle electrospinning. For temporally controlled release of gentamycin sulfate (GS) and desferoxamine (DFO), blend electrospun GS/polyvinyl alcohol (PVA) and coaxial electrospun core (PVA‐DFO)/shell (polycaprolactone; PCL) fibers were deposited in the scaffold. After a 25‐day time‐lapse release study in vitro, results showed GS released faster than DFO during the early stages and sustained release of DFO for long periods. For spatially controlled release of DFO, the vertically gradient gelatin/sodium alginate (SA) scaffolds presented to enable the release amount of DFO in a gradient mode. The experiment and test results demonstrate the validity of the 3D bioprinting platform integrated forming system and the excellent properties of such scaffolds for performing multidrug spatiotemporal release. POLYM. ENG. SCI., 56:170–177, 2016. © 2015 Society of Plastics Engineers     

Two-step modification process to improve mechanical properties and bioactivity of hydroxyfluorapatite scaffolds

Porous ceramic scaffolds are synthetic implants, which support cell migration and establish sufficient extracellular matrix (ECM) and cell-cell interactions to heal bone defects. Hydroxyapatite (HA) scaffolds is one of the most suitable synthetic scaffolds for hard tissue replacement due to their bioactivity, biocompatibility and biomimetic features. However, the major disadvantages of HA is poor mechanical properties as well as low degradability rate and apatite formation ability. In this study, we developed a new method to improve the bioactivity, biodegradability and mechanical properties of natural hydroxyfluorapatite (HFA) by applying two-step coating process including ceramic and polymer coats. The structure, morphology and bioactivity potential of the modified and unmodified nanocomposite scaffolds were evaluated using transmission electron microscopy (TEM), scanning electron microscopy (SEM), X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR) and energy dispersive spectroscopy (EDS). The scaffold with optimized mechanical properties was HFA-30?wt%HT (HT stands for hardystonite) with a total porosity and pore size of 89?±?1 and 900–1000?µm, respectively. The compressive modulus and strength of HFA (porosity ~ 93?±?1) were improved from 108.81?±?11.12–251.45?±?12.2?MPa and 0.46?±?0.1–1.7?±?0.3?MPa in HFA-30?wt%HT sample, respectively. After applying poly(ε-caprolactone fumarate) (PCLF) polymer coating, the compressive strength and modules increased to 2.8?±?0.15 and 426.1?±?15.14?MPa, respectively. The apatite formation ability of scaffolds was investigated using simulated body fluid (SBF). The results showed that applying the hardystonite coating improve the apatite formation ability; however, the release of ions increased the pH. Whereas, modified scaffolds with PCLF could control the release of ions and improve the apatite formation ability as well.     

Surface‐engineered hydroxyapatite nanocrystal/ poly(ε‐caprolactone) hybrid scaffolds for bone tissue engineering

To achieve novel polymer/bioceramic composite scaffolds for use in materials for bone tissue engineering, we prepared organic/inorganic hybrid scaffolds composed of biodegradable poly(ε‐caprolactone) (PCL) and hydroxyapatite (HA), which has excellent biocompatibility with hard tissues and high osteoconductivity and bioactivity. To improve the interactions between the scaffolds and osteoblasts, we focused on surface‐engineered, porous HA/PCL scaffolds that had HA molecules on their surfaces and within them because of the biochemical affinity between the biotin and avidin molecules. The surface modification of HA nanocrystals was performed with two different methods. Using Fourier transform infrared, X‐ray diffraction, and thermogravimetric analysis measurements, we found that surface‐modified HA nanocrystals prepared with an ethylene glycol mediated coupling method showed a higher degree of coupling (%) than those prepared via a direct coupling method. HA/PCL hybrid scaffolds with a well‐controlled porous architecture were fabricated with a gas‐blowing/particle‐leaching process. All HA/PCL scaffold samples exhibited approximately 80–85% porosity. As the HA concentration within the HA/PCL scaffolds increased, the porosity of the HA/PCL scaffolds gradually decreased. The homogeneous immobilization of biotin‐conjugated HA nanocrystals on a three‐dimensional, porous scaffold was observed with confocal microscopy. According to an in vitro cytotoxicity study, all scaffold samples exhibited greater than 80% cell viability, regardless of the HA/PCL composition or preparation method. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011     

Biocompatible scaffolds composed of chemically crosslinked chitosan and gelatin for tissue engineering

Chitosan‐based scaffolds are widely studied in tissue regeneration because of their biocompatibility and biodegradability. Scaffolds are obtained by different techniques and can be modified with other polymers allowing controlling their properties. This article discusses the assembling of three‐dimensional chitosan porous scaffolds blended with gelatin. Gelatin was used to enhance cells attachment due to the presence of cell adhesion motifs, while improving mechanical strength. 2,5‐dimethoxy‐2,5‐dihydrofurane (DHF) was used as the crosslinking agent, because it allowed to control the reaction kinetics through temperature, time and DHF concentration. The results indicate that scaffolds morphology, pore sizes and distribution, compressive moduli and biodegradation in vitro with lysozyme, can be customized with variations of gelatin content and crosslinking degree. Scaffolds were neither cytotoxic nor genotoxic for human keratinocytes, exhibiting cell–substrate interactions. Our findings demonstrated that chitosan–gelatin scaffolds crosslinked with DHF, as a new crosslinking agent, are suitable in tissue engineering applications. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016 , 133, 43814.     

Construction and evaluation of co-electrospun poly (butylene succinate)/gelatin materials as potential vascular grafts

In this study, a series of poly (butylene succinate) (PBSU)/gelatin composites were prepared by electrospinning. The morphology, physicochemical analysis, biomechanical properties, biocompatibility, and biodegradability of the materials were evaluated. The results showed that the ultimate tensile stress of the vascular PBSU/gelatin grafts at (95/5), (90/10), (85/15), and (80/20) was (4.17±0.54) MPa, (3.81±0.44) MPa, 2.94±0.69 MPa and 2.11±0.72 MPa respectively, and the burst pressure was (282.7±22.3) kPa, (295.3±3.9) kPa, (306.8±13.9) kPa and (307.6±9.0) kPa respectively, which met the requirements of tissue-engineered blood vessels. Furthermore, the addition of gelatin improved the hydrophilicity and degradation properties of PBSU, thus enhancing cell adhesion and promoting the inward growth of vascular smooth muscle cells. In summary, the research in this paper provides a useful reference for the preparation and optimization of vascular scaffolds.     

Preparation of chitosan-sodium alginate/bioactive glass composite cartilage scaffolds with high cell activity and bioactivity

Chitosan-sodium alginate/bioactive glass (CSB) composite cartilage scaffold with outstanding in vitro mineralization property and cytocompatibility is synthesized by freeze drying method. The effect of bioactive glass (BG) addition on the microstructure, porosity, swelling/degradation ratio, in vitro mineralization property and cytocompatibility of CSB scaffold is investigated by the characterization techniques of SEM, XRD, FTIR and BET. Results showed that CSB composite cartilage scaffold had a three-dimensional (3D) porous structure, and both porosity and average pore size met the requirements of cartilage tissue repair. Among, the typical CSB-1.0 had the largest overall pore size and lowest compressive modulus (1.083 ± 0.002 MPa). As the amount of BG increased, pore volume and porosity of CSB scaffolds gradually decreased, and the swelling and degradation ratios gradually reduced. After immersing in SBF for 3 d, cauliflower like hydroxyapatite (HA) was formed on CSB surface, indicating that the scaffold had good in vitro mineralization property. Moreover, the introduction of BG into the composite scaffold can improve the relative cell viability of MC3T3-E1 cells, and CSB-1.0 has the strongest ability to promote the proliferation of cells. Therefore, the as-obtained CSB scaffold can be used as a strong candidate for cartilage tissue engineering scaffold to meet clinical needs.     

Synthesis and characterization of poly(caprolactone triol succinate) elastomer for tissue engineering application

A novel polymer poly(caprolactone triol succinate) (PPCLSu) was synthesized from monomers polycaprolactone triol and succinic acid by direct polycondensation. The tensile strength of PPCLSu was found to be 0.33 ± 0.03 MPa with an elongation of 47.8 ± 1.9%. These elastomers lost about 7% of their original mass in an in vitro degradation study conducted in phosphate‐buffered saline (PBS) at 37°C up to 10 weeks. Three‐dimensional (3D) porous scaffolds were created by a porogen‐leaching method and these constructs were evaluated for primary rat osteoblast (PRO) proliferation and phenotype development in vitro. This elastomer promoted primary rat osteoblast adhesion, proliferation and increased expression of alkaline phosphatase, an early marker of osteoblastic phenotype. These preliminary results suggest that PPCLSu may be a good candidate material for scaffolding applications in tissue regeneration. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 130: 3770–3777, 2013     

Effect of nanocrystalline cellulose addition on needleless alternating current electrospinning and properties of nanofibrous polyacrylonitrile meshes

Needleless alternating current (AC)‐electrospinning is capable of achieving high nanofiber generation rates while adding more flexibility to the process development when compared to common direct current (DC)‐electrospinning. However, AC‐electrospinning process may produce very different results than DC‐electrospinning when using the same precursors. This study demonstrated that stable AC‐electrospinning of uniform and mechanically strong polyacrylonitrile (PAN) nanofibrous meshes can be achieved at 30 ± 5 kV rms voltage when 0.75–6.0 wt % of nanocrystalline cellulose‐II with respect to PAN is added to a typical PAN precursor solution. Efficient generation (up to 2 g/h rate or 0.7 g h^?1 cm^?2 mass flux) of nanofibers with 250–500 nm fiber diameters has been observed when using flat fiber‐generating electrodes with diameters up to 25 mm. Depending on the amount of nanocellulose, nanofibrous nanocellulose/PAN meshes revealed large variations in tensile modulus (90–273 MPa) and yield strength (1.0–2.5 MPa), whereas the fiber diameter, air permeability, air resistance, mesh porosity, and water absorption were less affected. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018 , 135, 45772.