Analysis of the Degradation Process of Alginate-Based Hydrogels in Artificial Urine for Use as a Bioresorbable Material in the Treatment of Urethral Injuries

Hydrogels from natural polymers such as sodium alginate have great potential in regenerative medicine because of their biocompatibility, biodegradability, mechanical properties, bioresorption ability, and relatively low cost. Sodium alginate, a polysaccharide derived from brown seaweed, is the most widely investigated and used biomaterial in biomedical applications. Alginate dressings are also useful as a delivery platform in order to provide a controlled release of therapeutic substances (e.g., pain-relieving, antibacterial, and anti-inflammatory agents). In our work, we aimed to analyze process of degradation of alginate hydrogels. We also describe an original hybrid crosslinking process by using not one, as usual, but a mixture of two crosslinking agents (calcium chloride and barium chloride). We proved that different crosslinking agents allow producing hydrogels with a spectrum of mechanical properties, similar to the urethra tissue. Hydrogels were formed using a dip-coating technique, and then examined by mechanical testing, FTIR (Fourier-Transform Infrared Spectroscopy), and resorption on artificial urine. Obtained hydrogels have a different degradation rate in artificial urine, and they can be used as a material for healing of urethra injuries, especially urethra strictures, which significantly affect the quality of life of patients.

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A Review of Water-Resistant Cellulose-Based Materials in Pharmaceutical and Biomedical Application

Current Medicinal Chemistry ◽

10.2174/0929867328666210208113354 ◽

2021 ◽

Vol 28 ◽

Author(s):

Bei He ◽

Xinxin Liu ◽

Shi Qi ◽

Run Zheng ◽

Minmin Chang ◽

...

Keyword(s):

Mechanical Properties ◽

Biomedical Application ◽

Drug Loading ◽

Cellulose Fibers ◽

Dip Coating ◽

Wound Dressings ◽

Attractive Alternative ◽

Natural Polymers ◽

Insoluble Drugs ◽

Good Biocompatibility

Background: Cellulose, huge reserves of natural polymers, have been widely applied in pharmaceutical and biomedicine fields due to its good biocompatibility, biodegradability, non-toxicity and excellent mechanical properties. At present, water-resistant metal-based and petroleum-based materials applied in medical field exists obvious problems of poor biocompatibility and high cost. Therefore, water-resistant cellulose-based materials with good biocompatibility and low price will become an attractive alternative. This review aims to summarize the preparation of water-resistant cellulose-based materials and their potential application in pharmaceutical and biomedical in recent years. Methods: Common hydrophobic treatments of cellulose fibers or paper were overviewed. The preparation, properties and applications of water-resistant cellulose-based materials in the pharmaceutical and biomedical fields were summarized. Results: Common hydrophobic treatments of cellulose fibers or paper were divided into chemical modification (graft polymerization, crosslinking, solution casting or dip-coating), physico-chemical surface modifications (plasma treatments, surface patterning, electrostatic spraying and electrowetting) and physical processing (electrostatic spinning, SAS process and 3D EHD printing). These hydrophobically processed cellulose fibers or paper could be prepared into various water-resistant cellulose-based materials and applied in pharmaceutical excipients, drug-loaded amphiphilic micelles, drug-loaded composite fibers, hydrophobic biocomposite film/coatings and paper-based detectors. They presented excellent water resistance and biocompatibility, low cytotoxicity and high drug loading ability, and stable drug release rate, etc., which could be used for water-insoluble drugs carriers, wound dressings, and medical testing equipment. Conclusion: Currently, water-resistant cellulose-based materials were mainly applied in water-insoluble drugs delivery carriers, wound dressing and medical diagnosis and presented great application prospects. However, the contradiction between hydrophobicity and mechanical properties of these reported water-resistant cellulose-based materials limited their wider application in biomedicine such as tissue engineering. In the future, attention will be focused on the higher hydrophobicity of water-resistant cellulose-based materials with excellent mechanical properties. In addition, clinical medical research of water-resistant cellulose-based materials should be strengthened.

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Biodegradable plastic modification from durian seed starch and shrimp chitosan with the addition of plasticiziers glycerol and polyglycerol using microwaves

Jurnal Pendidikan Kimia ◽

10.24114/jpkim.v13i3.29017 ◽

2021 ◽

Vol 13 (3) ◽

pp. 180-192

Author(s):

Saud Salomo ◽

◽

Astri Devi Br Pakpahan ◽

Dea Gracella Siagian ◽

Grecy Kristina Tampubolon ◽

...

Keyword(s):

Mechanical Properties ◽

Degradation Process ◽

Biodegradable Plastics ◽

Biodegradable Plastic ◽

Natural Polymers ◽

Speed Up ◽

Plastic Degradation ◽

Durian Seed ◽

Biodegradation Test

Plastic waste takes up to 450 years to decompose. These problems can be overcome by creating other alternatives, one of which is by using biodegradable plastic. Biodegradable plastics are plastics made from natural polymers that are easily degraded by microorganisms. This study aims to examine the effect of the amount of plasticizer on the length of the degradation process and the effect of using microwaves on the length of time for molding biodegradable plastic. This biodegradable plastic is made by combining durian seed starch, shrimp chitosan and plasticizers in the form of glycerol and polyglycerol with volume variations of 1 mL, 2 mL, 3 mL, 4 mL, and 5 mL. This polymerization was carried out using a microwave with a power of 100 watts for 60 minutes. The resulting biodegradable plastics were characterized using the FTIR test, the Mechanical Properties test, the Absorbency test, and the Biodegradation test to determine the quality of the biodegradable plastic. The results of this study indicate the greatest tensile strength value is 1.9768 MPa, the largest elongation value is 21.2772%, the smallest water absorption is 45.40% for 5 minutes, and the largest degraded mass is 0.908 grams for 7 days. Based on this research, it can be concluded that the use of polyglycerol can accelerate the plastic degradation process. In addition, the use of microwaves can speed up the molding time of biodegradable plastics.

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Sodium Alginate/Gelatine Hydrogels for Direct Bioprinting—The Effect of Composition Selection and Applied Solvents on the Bioink Properties

Materials ◽

10.3390/ma12172669 ◽

2019 ◽

Vol 12 (17) ◽

pp. 2669 ◽

Cited By ~ 7

Author(s):

Dorota Bociaga ◽

Mateusz Bartniak ◽

Jacek Grabarczyk ◽

Karolina Przybyszewska

Keyword(s):

Mechanical Properties ◽

Tissue Engineering ◽

Sodium Alginate ◽

Medical Devices ◽

Degradation Rate ◽

Culture Medium ◽

Biological Response ◽

Degradation Process ◽

Biological Properties ◽

Proliferation Ability

Hydrogels tested and evaluated in this study were developed for the possibility of their use as the bioinks for 3D direct bioprinting. Procedures for preparation and sterilization of hydrogels and the speed of the bioprinting were developed. Sodium alginate gelatine hydrogels were characterized in terms of printability, mechanical, and biological properties (viability, proliferation ability, biocompatibility). A hydrogel with the best properties was selected to carry out direct bioprinting tests in order to determine the parameters of the bioink, adapted to print with use of the designed and constructed bioprinter and provide the best conditions for cell growth. The obtained results showed the ability to control mechanical properties, biological response, and degradation rate of hydrogels through the use of various solvents. The use of a dedicated culture medium as a solvent for the preparation of a bioink, containing the predicted cell line, increases the proliferation of these cells. Modification of the percentage of individual components of the hydrogel gives the possibility of a controlled degradation process, which, in the case of printing of temporary medical devices, is a very important parameter for the hydrogels’ usage possibility—both in terms of tissue engineering and printing of tissue elements replacement, implants, and organs.

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Physical and Mechanical Properties of Natural Leaf Fiber-Reinforced Epoxy Polyester Composites

Polymers ◽

10.3390/polym13091369 ◽

2021 ◽

Vol 13 (9) ◽

pp. 1369

Author(s):

Sanjeev Kumar ◽

Lalta Prasad ◽

Vinay Kumar Patel ◽

Virendra Kumar ◽

Anil Kumar ◽

...

Keyword(s):

Mechanical Properties ◽

Composite Materials ◽

Synthetic Fibre ◽

Low Cost ◽

Fibre Length ◽

Physical And Mechanical Properties ◽

Natural Fibres ◽

Risk Environment ◽

Insulation Property ◽

Natural Leaf

In recent times, demand for light weight and high strength materials fabricated from natural fibres has increased tremendously. The use of natural fibres has rapidly increased due to their high availability, low density, and renewable capability over synthetic fibre. Natural leaf fibres are easy to extract from the plant (retting process is easy), which offers high stiffness, less energy consumption, less health risk, environment friendly, and better insulation property than the synthetic fibre-based composite. Natural leaf fibre composites have low machining wear with low cost and excellent performance in engineering applications, and hence established as superior reinforcing materials compared to other plant fibres. In this review, the physical and mechanical properties of different natural leaf fibre-based composites are addressed. The influences of fibre loading and fibre length on mechanical properties are discussed for different matrices-based composite materials. The surface modifications of natural fibre also play a crucial role in improving physical and mechanical properties regarding composite materials due to improved fibre/matrix adhesion. Additionally, the present review also deals with the effect of silane-treated leaf fibre-reinforced thermoset composite, which play an important role in enhancing the mechanical and physical properties of the composites.

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The brown seaweed Cystoseira schiffneri as a source of sodium alginate: Chemical and structural characterization, and antioxidant activities

Food Bioscience ◽

10.1016/j.fbio.2020.100873 ◽

2020 ◽

pp. 100873

Author(s):

Abdelkarim Benslima ◽

Sabrine Sellimi ◽

Marwa Hamdi ◽

Rim Nasri ◽

Mourad Jridi ◽

...

Keyword(s):

Sodium Alginate ◽

Structural Characterization ◽

Antioxidant Activities ◽

Brown Seaweed

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Preparation and Antimicrobial Activity of Chitosan and Its Derivatives: A Concise Review

Molecules ◽

10.3390/molecules26123694 ◽

2021 ◽

Vol 26 (12) ◽

pp. 3694

Author(s):

Luminita Georgeta Confederat ◽

Cristina Gabriela Tuchilus ◽

Maria Dragan ◽

Mousa Sha’at ◽

Oana Maria Dragostin

Keyword(s):

Antimicrobial Activity ◽

Low Cost ◽

Hydroxyl Groups ◽

Pharmacological Properties ◽

Natural Polymers ◽

Economic Sectors ◽

Physico Chemical ◽

Long Time ◽

Resistant Strains ◽

Strength And Durability

Despite the advantages presented by synthetic polymers such as strength and durability, the lack of biodegradability associated with the persistence in the environment for a long time turned the attention of researchers to natural polymers. Being biodegradable, biopolymers proved to be extremely beneficial to the environment. At present, they represent an important class of materials with applications in all economic sectors, but also in medicine. They find applications as absorbers, cosmetics, controlled drug delivery, tissue engineering, etc. Chitosan is one of the natural polymers which raised a strong interest for researchers due to some exceptional properties such as biodegradability, biocompatibility, nontoxicity, non-antigenicity, low-cost and numerous pharmacological properties as antimicrobial, antitumor, antioxidant, antidiabetic, immunoenhancing. In addition to this, the free amino and hydroxyl groups make it susceptible to a series of structural modulations, obtaining some derivatives with different biomedical applications. This review approaches the physico-chemical and pharmacological properties of chitosan and its derivatives, focusing on the antimicrobial potential including mechanism of action, factors that influence the antimicrobial activity and the activity against resistant strains, topics of great interest in the context of the concern raised by the available therapeutic options for infections, especially with resistant strains.

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Fabrication and Compressive Behavior of a Micro-Lattice Composite by High Resolution DLP Stereolithography

Polymers ◽

10.3390/polym13050785 ◽

2021 ◽

Vol 13 (5) ◽

pp. 785

Author(s):

Chow Shing Shin ◽

Yu Chia Chang

Keyword(s):

High Resolution ◽

Lattice Structure ◽

Low Cost ◽

Hierarchical Structures ◽

Dip Coating ◽

Unit Cell ◽

Digital Light Processing ◽

Unit Cell Size ◽

Wide Range ◽

And Performance

Lattice structures are superior to stochastic foams in mechanical properties and are finding increasing applications. Their properties can be tailored in a wide range through adjusting the design and dimensions of the unit cell, changing the constituent materials as well as forming into hierarchical structures. In order to achieve more levels of hierarchy, the dimensions of the fundamental lattice have to be small enough. Although lattice size of several microns can be fabricated using the two-photon polymerization technique, sophisticated and costly equipment is required. To balance cost and performance, a low-cost high resolution micro-stereolithographic system has been developed in this work based on a commercial digital light processing (DLP) projector. Unit cell lengths as small as 100 μm have been successfully fabricated. Decreasing the unit cell size from 150 to 100 μm increased the compressive stiffness by 26%. Different pretreatments to facilitate the electroless plating of nickel on the lattice structure have been attempted. A pretreatment of dip coating in a graphene suspension is the most successful and increased the strength and stiffness by 5.3 and 3.6 times, respectively. Even a very light and incomplete nickel plating in the interior has increase the structural stiffness and strength by more than twofold.

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Three-Dimensional Printable Hydrogel Using a Hyaluronic Acid/Sodium Alginate Bio-Ink

Polymers ◽

10.3390/polym13050794 ◽

2021 ◽

Vol 13 (5) ◽

pp. 794 ◽

Cited By ~ 1

Author(s):

Su Jeong Lee ◽

Ji Min Seok ◽

Jun Hee Lee ◽

Jaejong Lee ◽

Wan Doo Kim ◽

...

Keyword(s):

Tissue Engineering ◽

Hyaluronic Acid ◽

Sodium Alginate ◽

Three Dimensional ◽

Fibroblast Cell ◽

Chemical Crosslinking ◽

Fibroblast Cell Line ◽

Engineering Applications ◽

Encapsulated Cells ◽

Crosslinking Agents

Bio-ink properties have been extensively studied for use in the three-dimensional (3D) bio-printing process for tissue engineering applications. In this study, we developed a method to synthesize bio-ink using hyaluronic acid (HA) and sodium alginate (SA) without employing the chemical crosslinking agents of HA to 30% (w/v). Furthermore, we evaluated the properties of the obtained bio-inks to gauge their suitability in bio-printing, primarily focusing on their viscosity, printability, and shrinkage properties. Furthermore, the bio-ink encapsulating the cells (NIH3T3 fibroblast cell line) was characterized using a live/dead assay and WST-1 to assess the biocompatibility. It was inferred from the results that the blended hydrogel was successfully printed for all groups with viscosities of 883 Pa∙s (HA, 0% w/v), 1211 Pa∙s (HA, 10% w/v), and 1525 Pa∙s, (HA, 30% w/v) at a 0.1 s−1 shear rate. Their structures exhibited no significant shrinkage after CaCl2 crosslinking and maintained their integrity during the culture periods. The relative proliferation rate of the encapsulated cells in the HA/SA blended bio-ink was 70% higher than the SA-only bio-ink after the fourth day. These results suggest that the 3D printable HA/SA hydrogel could be used as the bio-ink for tissue engineering applications.

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