Promoting effect of nano hydroxyapatite and vitamin D3 on the osteogenic differentiation of human adipose-derived stem cells in polycaprolactone/gelatin scaffold for bone tissue engineering

Tissue engineering knowledge is a step towards the treatment of irreversible damages to human beings. In the present study, PCL/Gel, PCL/Gel/nHA, PCL/Gel/Vit D3 and PCL/Gel/nHA/Vit D3 (Polycaprolactone/Gelatin/Nanohydroxyapatite/Vitamin D3) composite scaffolds were successfully constructed using electrospinning method. The proliferation and differentiation of hADSCs into the bone phenotype were determined using MTT method, ALP activity, Von Kossa and Alizarin red staining, and qRT-PCR test. The simultaneous presence of nHA and vitamin D3 led to the increased activity of ALP in the early stages (on the 14th day) and increased mineralization in the late stages (on the 21st day) in differentiated hADSCs. Further, it was found that the use of nHA and vitamin D3 resulted in increased expression of BGLAP and COLL I and reduced expression of ALP and RUNX2 in hADSCs for 21 days. The results indicated that nHA and vitamin D3 have a synergistic effect on the osteogenic differentiation of hADSCs.Peer reviewe

Preparation and Evaluation of Blood Compatibility of NovelEpoxy-Modified Polyurethanes: Blood compatible polyurethanes

In order to prepare polyurethane elastomers with acceptable physical properties and good biocompatibility, novel polyurethane networks were synthesized via curing reaction of epoxy-terminated polyurethane prepolymers (EUPs) with hexamethylene diamine. EUPs were prepared from reaction of glycidol with NCO-terminated polyurethanes (ITPs). ITPs were also synthesized from reaction of one equivalent of either poly(tetramethylene ether)glycol or poly(ethylene glycol) with hexamethylene diisocyanate. Cytotoxcicity and blood compatibility were evaluated.All of the prepared polymers via this novel and simple method showed nontoxic behavior and acceptable blood compatibility

Solvothermal synthesis of magnetic spinel ferrites

At present, solvothermal fabrication method has widely been applied in the synthesis of spinel ferrite nanoparticles (SFNs), which is mainly because of its great advantages such as precise control over size, shape distribution, and high crystallinity that do not require postannealing treatment. Among various SFNs, Fe3O4nanoparticles have attracted tremendous attention because of their favorable physical and structural properties which are advantageous, especially in biomedical applications, among which the vast application of these materials as targeted drug delivery systems, hyperthermia, and imaging agents in cancer therapy can be mentioned. The main focus of this study is to present an introduction to solvothermal method and key synthesis parameters of SFNs through this synthesis route. Moreover, most recent progress on the potential applications of Fe3O4nanoparticles as the most important compound among the spinel ferrites family members is discussed

Comparison of the Effect of Hydrophilicity on Biocompatibilityand Platelet Adhesion of Two Different Kinds of Biomaterials: Effect of hydrophilicity on biocompatibility of biomaterialsRoswell

Determination of blood compatibility is an important problem in blood contactingdevices. In this study, two classes of materials including polyurethane (based onpolyethylene glycol and poly tetrametylene oxide) and polyvinyl alcohol samples,with different hydrophilicity properties were synthesized and their physico-chemicalproperties were compared. Water uptake ratio, FTIR spectroscopy, and contactangle measurement were conducted. In vitrobiocompatibility experiments wereundertaken using L-929 fibroblast cell lines which demonstrated desired cellviability for all samples after 7 days. The adhesion of platelets from human plasmawas studied by optical microscopy. Blood coagulation time were also determinedwhich revealed polyurethane based poly tetramethylene oxide has better interactionby blood elements among all samples

Synthesis and Characterization of Biodegradable HemostatGelatin Sponge forSurgery Application: Biodegradable hemostat gelatin sponge

Production and characterization of soft cross-linked gelatin sponge by using glutaraldehyde for blood hemostasis application, is the goal of this study.Biodegradable hydrogels were prepared through crosslinking of gelatin with glutaraldehyde followed by freeze drying. The effects of gelatin concentration, amount of crosslink agent and freeze drying temperature on mechanical properties andelasticity, stability and degradation rate, swelling and water absorption ability,hemostatic effect and cytotoxicity were investigated. As the freezing temperature was lowered, the density of freeze-dried sponges increased. Density of samples is strongly dependent on the freezing temperature before freeze-drying. The addition of GTAas cross linker agent changed density very slightly, but no direct relationship between the amount of cross linker and the density was observed. Gelatin sponges prepared by freeze-drying after freezing at -10 and -25 ºC had large pores. Network structure of heterogeneous pores. The rate of weight loss decreased with increasing degree of crosslinking of the samples, and the higher degree of cross-linking in gelatin sponges causes more resistance to degradation in PBS solution. Gelatin concentration increase had very sharp effect on raising the compression module, and freezing temperature changed inner structure of sponges and can affect mechanical behavior

Electrospun Polycaprolactone/lignin-based Nanocomposite as a Novel Tissue Scaffold for Biomedical Applications

Background: Biopolymer scaffolds have received great interest in academic and industrial environment because of their supreme characteristics like biological, mechanical, chemical, and cost saving in the biomedical science. There are various attempts for incorporation of biopolymers with cheap natural micro- or nanoparticles like lignin (Lig), alginate, and gums to prepare new materials with enhanced properties. Methods: In this work, the electrospinning (ELS) technique as a promising cost-effective method for producing polymeric scaffold fibers was used, which mimics extracellular matrix structure for soft tissue engineering applications. Nanocomposites of Lig and polycaprolactone (PCL) scaffold produced with ELS technique. Nanocomposite containings (0, 5, 10, and 15 wt.%) of Lig were prepared with addition of Lig powder into the PCL solution while stirring at the room temperature. The bioactivity, swelling properties, morphological and mechanical tests were conducted for all the samples to investigate the nanocomposite scaffold features. Results: The results showed that scaffold with 10 wt.% Lig have appropriate porosity, biodegradation, minimum fiber diameter, optimum pore size as well as enhanced tensile strength, and young modulus compared with pure PCL. Degradation test performed through immersion of samples in the phosphate-buffer saline showed that degradation of PCL nanocomposites could accelerate up to 10% due to the addition of Lig. Conclusions: Electrospun PCL-Lig scaffold enhanced the biological response of the cells with the mechanical signals. The prepared nanocomposite scaffold can choose for potential candidate in the biomedical science

Osteogenic Differentiation of Adipose-Derived Mesenchymal Stem Cells Using 3D-Printed PDLLA/ β-TCP Nanocomposite Scaffolds

Designing bone scaffolds containing both organic and inorganic composites simulating the architecture of the bone is the most important principle in bone tissue engineering. The objective of this study was to fabricate a composite scaffold containing poly (D, l)-lactide (PDLLA) and β-tricalcium phosphate (β-TCP) as a platform for osteogenic differentiation of adipose-derived mesenchymal stem cells. In this study, PDLLA/β-TCP scaffolds were fabricated using three-dimensional printing (3D) technology through melt excursion technique. The physicomechanical characteristics, including microstructure, mechanical properties, of the customized scaffolds were investigated. Further, the in vitro biological characteristics of manufactured scaffolds were evaluated in conjugation with buccal fat pad derived mesenchymal stem cells in terms of cell attachment, viability, proliferation, and osteogenic differentiation capacity. The 3D printed customized scaffold in this study showed proper pore size, porosity, mechanical strength, material composition, biocompatibility, and osteogenic differentiation capacity. The obtained results converge to reveal the promising features of the nanocomposite 3D printed platform for personalized bone tissue engineering

Polyurethane-Nanolignin Composite Foam Coated with Propolis as a Platform for Wound Dressing: Synthesis and Characterization

This piece of research explores porous nanocomposite polyurethane (PU) foam synthesis, containing nanolignin (NL), coated with natural antimicrobial propolis for wound dressing. PU foam was synthesized using polyethylene glycol, glycerol, NL, and 1, 6-diisocyanato-hexane (NCO/OH ratio: 1.2) and water as blowing agent. The resultant foam was immersed in ethanolic extract of propolis (EEP). PU, NL-PU, and PU-NL/EEP foams were characterized from mechanical, morphological, and chemical perspectives. NL Incorporation into PU increased mechanical strength, while EEP coating showed lower strength than PU-NL/EEP. Morphological investigations confirmed an open-celled structure with a pore diameter of 150–200 μm, a density of nearly 0.2 g/cm3,, and porosity greater than 85%, which led to significantly high water absorption (267% for PU-NL/EEP). The hydrophilic nature of foams, measured by the contact angle, proved to be increased by NL addition and EEP coating. PU and PU-NL did not show important antibacterial features, while EEP coating resulted in a significant antibacterial efficiency. All foams revealed high biocompatibility toward L929 fibroblasts, with the highest cell viability and cell attachment for PU-NL/EEP. In vivo wound healing using Wistar rats’ full-thickness skin wound model confirmed that PU-NL/EEP exhibited an essentially higher wound healing efficacy compared with other foams. Hence, PU-NL/EEP foam could be a promising wound dressing candidate

A 3D Nanostructured Calcium-Aluminum-Silicate Scaffold with Hierarchical Meso-Macroporosity for Bone Tissue Regeneration: Fabrication, Sintering Behavior, Surface Modification and in Vitro Studies

This is a comprehensive study reporting the fabrication of highly porous Gehlenite scaffold (Ca2Al2SiO7)—both with and without surface modification—for the first time. The sintering temperature of Gehlenite scaffolds was optimized. Next, the optimized Gehlenite scaffold was coated by polycaprolactone (PCL)-Forsterite (Mg2SiO4) nanocomposite to improve the scaffold’s brittleness and biological properties. 1375 °C was found to be the optimized sintering temperature by which the Gehlenite scaffold was consolidated. Different PCL and Forsterite concentrations were separately applied on the optimized scaffold to yield a complete nanocomposite coating without clogging the macroporous structure. The bioactivity, degradation rate, cell viability, attachment and proliferation of three different scaffolds—non-coated (sintered at 1375 °C), PCL-coated and PCL/Forsterite nanocomposite-coated—were scrutinized and compared to each other in vitro. Based on our results, it is concluded that the PCL-Forsterite nanocomposite-coated scaffold with desired physical, chemical and biological-related properties has a great potential for bone tissue regeneration