scholarly journals Elastin-Coated Biodegradable Photopolymer Scaffolds for Tissue Engineering Applications

2014 ◽  
Vol 2014 ◽  
pp. 1-9 ◽  
Author(s):  
Rossella Barenghi ◽  
Szabolcs Beke ◽  
Ilaria Romano ◽  
Paola Gavazzo ◽  
Balázs Farkas ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
Neointimal Hyperplasia ◽  
Polymer Surface ◽  
Polymeric Materials ◽  
Promising Candidate ◽  
Huvec Cell ◽  
New Material ◽  
Polymer Interaction ◽  
Open Issues

One of the main open issues in modern vascular surgery is the nonbiodegradability of implants used for stent interventions, which can lead to small caliber-related thrombosis and neointimal hyperplasia. Some new, resorbable polymeric materials have been proposed to substitute traditional stainless-steel stents, but so far they were affected by poor mechanical properties and low biocompatibility. In this respect, a new material, polypropylene fumarate (PPF), may be considered as a promising candidate to implement the development of next generation stents, due to its complete biodegradability, and excellent mechanical properties and the ease to be precisely patterned. Besides all these benefits, PPF has not been tested yet for vascular prosthesis, mainly because it proved to be almost inert, while the ability to elicit a specific biological function would be of paramount importance in such critical surgery applications. Here, we propose a biomimetic functionalization process, aimed at obtaining specific bioactivation and thus improved cell-polymer interaction. Porous PPF-based scaffolds produced by deep-UV photocuring were coated by elastin and the functionalized scaffolds were extensively characterized, revealing a stable bound between the protein and the polymer surface. Both 3T3 and HUVEC cell lines were used forin vitrotests displaying an enhancement of cells adhesion and proliferation on the functionalized scaffolds.

scholarly journals Anti-Inflammatory Properties of Injectable Betamethasone-Loaded Tyramine-Modified Gellan Gum/Silk Fibroin Hydrogels

Biomolecules ◽  
2020 ◽  
Vol 10 (10) ◽  
pp. 1456
Author(s):  
Isabel Matos Oliveira ◽  
Cristiana Gonçalves ◽  
Myeong Eun Shin ◽  
Sumi Lee ◽  
Rui Luis Reis ◽  
...  
Keyword(s):  
Rheumatoid Arthritis ◽  
Mechanical Properties ◽  
Silk Fibroin ◽  
Therapeutic Efficacy ◽  
Composite Structures ◽  
Gelation Time ◽  
Polymeric Materials ◽  
Gellan Gum ◽  
Traditional Use

Rheumatoid arthritis is a rheumatic disease for which a healing treatment does not presently exist. Silk fibroin has been extensively studied for use in drug delivery systems due to its uniqueness, versatility and strong clinical track record in medicine. However, in general, natural polymeric materials are not mechanically stable enough, and have high rates of biodegradation. Thus, synthetic materials such as gellan gum can be used to produce composite structures with biological signals to promote tissue-specific interactions while providing the desired mechanical properties. In this work, we aimed to produce hydrogels of tyramine-modified gellan gum with silk fibroin (Ty–GG/SF) via horseradish peroxidase (HRP), with encapsulated betamethasone, to improve the biocompatibility and mechanical properties, and further increase therapeutic efficacy to treat rheumatoid arthritis (RA). The Ty–GG/SF hydrogels presented a β-sheet secondary structure, with gelation time around 2–5 min, good resistance to enzymatic degradation, a suitable injectability profile, viscoelastic capacity with a significant solid component and a betamethasone-controlled release profile over time. In vitro studies showed that Ty–GG/SF hydrogels did not produce a deleterious effect on cellular metabolic activity, morphology or proliferation. Furthermore, Ty–GG/SF hydrogels with encapsulated betamethasone revealed greater therapeutic efficacy than the drug applied alone. Therefore, this strategy can provide an improvement in therapeutic efficacy when compared to the traditional use of drugs for the treatment of rheumatoid arthritis.

Mechanical Properties of Newly Developed Root Canal Sealers Containing Titanium Oxide

2007 ◽  
Vol 361-363 ◽  
pp. 845-848
Author(s):  
Ayami Nakamura ◽  
Harumasa Wanibe ◽  
Akihiro Iwama ◽  
Naritaka Kitamura ◽  
Naoki Shibata ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
Catalytic Activity ◽  
Titanium Oxide ◽  
Root Canal ◽  
Physical Characteristics ◽  
Clinical Use ◽  
Root Canal Sealer ◽  
New Material ◽  
Root Canal Sealers

Titanium oxide (TiO2) has lately attracted considerable attention as a new material in dentistry because of its catalytic activity and biocompatibility. In the present study, we developed a novel root canal sealer consisting of TiO2 and evaluated its mechanical properties in vitro. The newly developed root canal sealer containing TiO2 has satisfied the requirement of ISO formulation 6876. Our results suggest that the newly developed root canal sealer has excellent physical characteristics, which may make it suitable for clinical use as a root canal sealer material.

scholarly journals A Review on the Adaption of Alginate-Gelatin Hydrogels for 3D Cultures and Bioprinting

Materials ◽  
2021 ◽  
Vol 14 (4) ◽  
pp. 858
Author(s):  
Magdalena B. Łabowska ◽  
Karolina Cierluk ◽  
Agnieszka M. Jankowska ◽  
Julita Kulbacka ◽  
Jerzy Detyna ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
3D Printing ◽  
Cell Cultures ◽  
Polymeric Materials ◽  
Optimal Growth ◽  
Vital Functions ◽  
Wide Range ◽  
In Vitro Cell Cultures ◽  
Living Tissues

Sustaining the vital functions of cells outside the organism requires strictly defined parameters. In order to ensure their optimal growth and development, it is necessary to provide a range of nutrients and regulators. Hydrogels are excellent materials for 3D in vitro cell cultures. Their ability to retain large amounts of liquid, as well as their biocompatibility, soft structures, and mechanical properties similar to these of living tissues, provide appropriate microenvironments that mimic extracellular matrix functions. The wide range of natural and synthetic polymeric materials, as well as the simplicity of their physico-chemical modification, allow the mechanical properties to be adjusted for different requirements. Sodium alginate-based hydrogel is a frequently used material for cell culture. The lack of cell-interactive properties makes this polysaccharide the most often applied in combination with other materials, including gelatin. The combination of both materials increases their biological activity and improves their material properties, making this combination a frequently used material in 3D printing technology. The use of hydrogels as inks in 3D printing allows the accurate manufacturing of scaffolds with complex shapes and geometries. The aim of this paper is to provide an overview of the materials used for 3D cell cultures, which are mainly alginate–gelatin hydrogels, including their properties and potential applications.

In Vitro Mechanical Properties of Metallocene Linear Low Density Polyethylene (mLLDPE) Nanocomposites Incorporating Montmorillonite (MMT)

2015 ◽  
Vol 754-755 ◽  
pp. 24-28 ◽  
Author(s):  
Azlin Fazlina Osman ◽  
Abdulkader M. Alakrach ◽  
Hussein Kalo ◽  
Omar Sabbar Dahham ◽  
Mohd Mustafa Al Bakri Abdullah
Keyword(s):  
Mechanical Properties ◽  
Mechanical Property ◽  
Biomedical Application ◽  
Property Values ◽  
Low Density Polyethylene ◽  
Low Density ◽  
Linear Low Density Polyethylene ◽  
Organically Modified ◽  
New Material

The viability of metallocene linear low density polyethylene (mLLDPE) nanocomposites is being investigated as a new material for biomedical application. The effect of filler loadings on the ambient andin vitro(after being exposed in oxidizing condition, 37°C) mechanical properties was studied. We observed that, the mLLDPE nanocomposites have higher mechanical property values as compared to the neat mLLDPE. Furthermore, these properties were less affected by thein vitroconditions. The best ambient andin vitromechanical properties were achived when 3wt% of organically modified MMT (organo-MMT) was added into the mLLDPE. It was postulated that the presence of MMT layered structure introduced a more tortous path for the diffusing of oxidant molecules, thereby decreasing their permeability towards mLLDPE molecular chains. The smaller amount of oxidants entering the molecular chains resulted in greater retention of mechanical properties when testedin vitro. This preliminary biostability studies show promising properties of the mLLDPE nanocomposite which possess the potential to be further developed for biomedical devices.

Cell Interactions With Polymers

2004 ◽  
Author(s):  
W. Mark Saltzman
Keyword(s):  
Cell Viability ◽  
Biomedical Applications ◽  
Polymer Surface ◽  
Polymeric Materials ◽  
Cell Interactions ◽  
Cell Culture Techniques ◽  
Culture Techniques ◽  
Wide Range

Synthetic and natural polymers are an important element in new strategies for producing engineered tissue. Polymers are currently used in a wide range of biomedical applications, including applications in which the polymer remains in intimate contact with cells and tissues for prolonged periods. As discussed in Chapter 1, several classes of polymers have proven to be most useful in biomedical applications and, therefore, might be appropriate for tissue engineering applications. To produce tissue-engineered materials composed of polymers and cells, however, it is first necessary to understand the influence of these polymeric materials on cell viability, growth, and function. Cell interactions with polymers are usually studied using cell culture techniques. While in vitro studies do not reproduce the wide range of cellular responses observed following implantation of materials, the culture environment provides a level of control and quantification that cannot usually be obtained in vivo. Cells in culture are generally plated over a polymer surface and the extent of cell adhesion and spreading on the surface can be measured. By maintaining the culture for longer periods the influence of the substrate on cell viability, function, and motility can also be determined. Since investigators use different techniques to assess cell interactions with polymers, and because the differences between techniques are critically important for interpretation of interactions, some of the most frequently used in vitro methods are reviewed in this section. Before any measurement of cell interaction with a polymer substrate can be attempted, the polymeric material and the cells must come into contact. Preferably, this contact should be controlled (or at least understood) by the experimentalist. This is a critical, and often overlooked, aspect of all of these measurements. Some materials are easily fabricated in a format suitable for study; polystyrene films, for example, are transparent, durable, and strong. Other materials must be coated onto a rigid substrate (such as a glass coverslip) prior to study. Cell function is sensitive to chemical, morphological, and mechanical properties of the surface; therefore, almost every aspect of material preparation can introduce variables that are known to influence cell interactions.

Binding of Tissue Plasminogen Activator to Vascular Grafts

1989 ◽  
Vol 61 (01) ◽  
pp. 131-136 ◽  
Author(s):  
Richard A Harvey ◽  
Hugh C Kim ◽  
Jonathan Pincus ◽  
Stanley Z Trooskin ◽  
Josiah N Wilcox ◽  
...  
Keyword(s):  
Plasminogen Activator ◽  
Tissue Plasminogen Activator ◽  
Fibrinolytic Activity ◽  
Polymer Surface ◽  
Enzymic Activity ◽  
Vascular Prostheses ◽  
Chemically Modified ◽  
Insoluble Surfactant ◽  
Tissue Plasminogen

SummaryTissue plasminogen activator labeled with radioactive iodine (125I-tPA) was immobilized on vascular prostheses chemically modified with a thin coating of water-insoluble surfactant, tridodecylmethylammonium chloride (TDM AC). Surfactant- treated Dacron, polytetrafluoroethylene (PTFE), silastic, polyethylene and polyurethane bound appreciable amounts of 125I- tPA (5-30 μg 125I-tPA/cm2). Upon exposure to human plasma, the amount of 125I-tPA bound to the surface shows an initial drop during the first hour of incubation, followed by a slower, roughly exponential release with a t½ of appoximately 75 hours. Prostheses containing bound tPA show fibrinolytic activity as measured both by lysis of clots formed in vitro, and by hydrolysis of a synthetic polypeptide substrate. Prior to incubation in plasma, tPA bound to a polymer surface has an enzymic activity similar, if not identical to that of the native enzyme in buffered solution. However, exposure to plasma causes a decrease in the fibrinolytic activity of both bound tPA and enzyme released from the surface of the polymer. These data demonstrate that surfactant-treated prostheses can bind tPA, and that these chemically modified devices can act as a slow-release drug delivery system with the potential for reducing prosthesis-induced thromboembolism.

Cytocompatibility and Material Properties of Poly-carbonate Urethane/Carbon Nanofiber Composites for Neural Applications

2003 ◽  
Vol 774 ◽  
Author(s):  
Janice L. McKenzie ◽  
Michael C. Waid ◽  
Riyi Shi ◽  
Thomas J. Webster
Keyword(s):  
Mechanical Properties ◽  
Carbon Nanofibers ◽  
Material Properties ◽  
Carbon Nanofiber ◽  
Scar Tissue ◽  
Tissue Response ◽  
Positive Interactions ◽  
Weight Percentage ◽  
Poly Carbonate

AbstractCarbon nanofibers possess excellent conductivity properties, which may be beneficial in the design of more effective neural prostheses, however, limited evidence on their cytocompatibility properties exists. The objective of the present in vitro study was to determine cytocompatibility and material properties of formulations containing carbon nanofibers to predict the gliotic scar tissue response. Poly-carbonate urethane was combined with carbon nanofibers in varying weight percentages to provide a supportive matrix with beneficial bulk electrical and mechanical properties. The substrates were tested for mechanical properties and conductivity. Astrocytes (glial scar tissue-forming cells) were seeded onto the substrates for adhesion. Results provided the first evidence that astrocytes preferentially adhered to the composite material that contained the lowest weight percentage of carbon nanofibers. Positive interactions with neurons, and, at the same time, limited astrocyte functions leading to decreased gliotic scar tissue formation are essential for increased neuronal implant efficacy.

Possibilities of using biodegradable polymeric materials in the agricultural sector

2020 ◽  
Vol 67 (2) ◽  
pp. 115-120
Author(s):  
Raisa A. Alekhina ◽  
Victoriya E. Slavkina ◽  
Yuliya A. Lopatina
Keyword(s):  
Mechanical Properties ◽  
Biodegradable Polymers ◽  
Biodegradable Polymer ◽  
Agricultural Sector ◽  
Polymeric Materials ◽  
Polymer Materials ◽  
Limiting Factors ◽  
Research Purpose ◽  
Biodegradable Materials ◽  
Advantages And Disadvantages

The article presents options for recycling polymers. The use of biodegradable materials is promising. This is a special class of polymers that can decompose under aerobic or anaerobic conditions under the action of microorganisms or enzymes forming natural products such as carbon dioxide, nitrogen, water, biomass, and inorganic salts. (Research purpose) The research purpose is in reviewing biodegradable materials that can be used for the manufacture of products used in agriculture. (Materials and methods) The study are based on open information sources containing information about biodegradable materials. Research methods are collecting, studying and comparative analysis of information. (Results and discussion) The article presents the advantages and disadvantages of biodegradable materials, mechanical properties of the main groups of biodegradable polymers. The article provides a summary list of agricultural products that can be made from biodegradable polymer materials. It was found that products from the general group are widely used in agriculture. Authors have found that products from a special group can only be made from biodegradable polymers with a controlled decomposition period in the soil, their use contributes to increasing the productivity of crops. (Conclusions) It was found that biodegradable polymer materials, along with environmental safety, have mechanical properties that allow them producing products that do not carry significant loads during operation. We have shown that the creation of responsible products (machine parts) from biodegradable polymers requires an increase in their strength properties, which is achievable by creating composites based on them. It was found that the technological complexity of their manufacture and high cost are the limiting factors for the widespread use of biodegradable polymers at this stage.

Sign in / Sign up

Export Citation Format

Share Document