Hyaluronic Acid/Oxidized К-Carrageenan Electrospun Nanofibers Synthesis and Antibacterial Properties

Chitosan-carrageenan microbeads containing nano-encapsulated curcumin: Nano-in-micro hydrogels as alternative-therapeutics for resistant pathogens associated with chronic wounds

Antimicrobial resistance is an issue of global relevance for the treatment of chronic wound infections. In this study, nano-in-micro hydrogels (microbeads) of chitosan and κ-carrageenan (CCMBs) containing curcumin-loaded rhamnosomes (Cur-R) were developed. The potential of Cur-R-CCMBs for improving the antibacterial activity and sustained release of curcumin was evaluated. Curcumin-loaded rhamnosomes (rhamnolipids functionalized liposomes) had a mean particle size of 116 ± 7 nm and a surface-charge of -24.5 ± 9.4 mV. The encapsulation efficiency of curcumin increased from 42.83 % ± 0.69 % in Cur-R to 95.24 % ± 3.61 % respectively after their embedding in CCMBs. SEM revealed smooth surface morphology of Cur-R-CCMBs. FTIR spectroscopy confirmed the presence of weak electrostatic and hydrophobic interactions among curcumin, rhamnosomes, and microbeads. Cur-R-CCMBs had demonstrated significant antibacterial activity against multi-drug resistant chronic wound pathogens including Staphylococcus aureus and Pseudomonas aeruginosa. Cur-R-CCMBs also exhibited significantly higher anti-oxidant (76.85 % ± 2.12 %) and anti-inflammatory activity (91.94 % ± 0.41 %) as well as hemocompatibility (4.024 % ± 0.59 %) as compared to pristine microbeads. In vivo infection model of mice revealed significant reduction in the viable bacterial count of S. aureus (∼2.5 log CFU/mL) and P. aeruginosa (∼2 log CFU/mL) for Cur-R-CCMBs after 5 days. Therefore, nano-in-micro hydrogels can improve the overall efficacy of hydrophobic antimicrobials to develop effective alternative-therapeutics against resistant-pathogens associated with chronic wound infections.

Tailor-Made Polysaccharides for Biomedical Applications

Polysaccharides (PSAs) are carbohydrate-based macromolecules widely used in the biomedical field, either in their pure form or in blends/nanocomposites with other materials. The relationship between structure, properties, and functions has inspired scientists to design multifunctional PSAs for various biomedical applications by incorporating unique molecular structures and targeted bulk properties. Multiple strategies, such as conjugation, grafting, cross-linking, and functionalization, have been explored to control their mechanical properties, electrical conductivity, hydrophilicity, degradability, rheological features, and stimuli-responsiveness. For instance, custom-made PSAs are known for their worldwide biomedical applications in tissue engineering, drug/gene delivery, and regenerative medicine. Furthermore, the remarkable advancements in supramolecular engineering and chemistry have paved the way for mission-oriented biomaterial synthesis and the fabrication of customized biomaterials. These materials can synergistically combine the benefits of biology and chemistry to tackle important biomedical questions. Herein, we categorize and summarize PSAs based on their synthesis methods, and explore the main strategies used to customize their chemical structures. We then highlight various properties of PSAs using practical examples. Lastly, we thoroughly describe the biomedical applications of tailor-made PSAs, along with their current existing challenges and potential future directions.

Synthesis of biocomposites from microalgal peptide incorporated polycaprolactone/ κ- carrageenan nanofibers and their antibacterial and wound healing property

Antimicrobial peptides (AMPs) are promising novel agents for targeting a wide range of pathogens. In this study, microalgal peptides derived from native microalgae were incorporated into polycaprolactone (PCL) with ƙ-Carrageenan (ƙ-C) forming nanofibers using the electrospinning method. The peptides incorporated in the nanofibers were characterized by fourier infrared spectroscopy, thermogravimetric analysis, scanning electron microscopy (SEM), and contact angle measurement. The results showed that peptides with molecular weights < 10 kDa, when loaded into nanofibers, exhibited lower wettability. The SEM analysis revealed a thin, smooth, interconnected bead-like structures. The antimicrobial activity of the electrospun nanofibers was evaluated through disc diffusion, and minimum inhibitory activity against Escherichia coli (MTTC 443), and Staphylococcus aureus (MTTC 96), resulting in zones of inhibition of 24 ± 0.5 mm and 14 ± 0.5 mm, respectively. The in vitro biocompatibility of the synthesized nanofibers was confirmed using in HEK 293 cell lines with an increased cell viability. Interestingly, the fibers also exhibited a significant wound-healing properties when used in vitro scratch assays. In conclusion, algal peptides incorporated with PCL/ ƙ-C were found to exhibit antimicrobial and biocompatible biomaterials for wound healing applications.

Marine-derived polysaccharides and their therapeutic potential in wound healing application - A review

Polysaccharides originating from marine sources have been studied as potential material for use in wound dressings because of their desirable characteristics of biocompatibility, biodegradability, and low toxicity. Marine-derived polysaccharides used as wound dressing, provide several benefits such as promoting wound healing by providing a moist environment that facilitates cell migration and proliferation. They can also act as a barrier against external contaminants and provide a protective layer to prevent further damage to the wound. Research studies have shown that marine-derived polysaccharides can be used to develop different types of wound dressings such as hydrogels, films, and fibres. These dressings can be personalised to meet specific requirements based on the type and severity of the wound. For instance, hydrogels can be used for deep wounds to provide a moist environment, while films can be used for superficial wounds to provide a protective barrier. Additionally, these polysaccharides can be modified to improve their properties, such as enhancing their mechanical strength or increasing their ability to release bioactive molecules that can promote wound healing. Overall, marine-derived polysaccharides show great promise for developing effective and safe wound dressings for various wound types.

Polysaccharide-based antibacterial coating technologies

To tackle antimicrobial resistance, a global threat identified by the United Nations, is a common cause of healthcare-associated infections (HAI) and is responsible for significant costs on healthcare systems, a substantial amount of research has been devoted to developing polysaccharide-based strategies that prevent bacterial attachment and biofilm formation on surfaces. Polysaccharides are essential building blocks for life and an abundant renewable resource that have attracted much attention due to their intrinsic remarkable biological potential antibacterial activities. If converted into efficient antibacterial coatings that could be applied to a broad range of surfaces and applications, polysaccharide-based coatings could have a significant potential global impact. However, the ultimate success of polysaccharide-based antibacterial materials will be determined by their potential for use in manufacturing processes that are scalable, versatile, and affordable. Therefore, in this review we focus on recent advances in polysaccharide-based antibacterial coatings from the perspective of fabrication methods. We first provide an overview of strategies for designing polysaccharide-based antimicrobial formulations and methods to assess the antibacterial properties of coatings. Recent advances on manufacturing polysaccharide-based coatings using some of the most common polysaccharides and fabrication methods are then detailed, followed by a critical comparative overview of associated challenges and opportunities for future developments. STATEMENT OF SIGNIFICANCE: Our review presents a timely perspective by being the first review in the field to focus on advances on polysaccharide-based antibacterial coatings from the perspective of fabrication methods along with an overview of strategies for designing polysaccharide-based antimicrobial formulations, methods to assess the antibacterial properties of coatings as well as a critical comparative overview of associated challenges and opportunities for future developments. Meanwhile this work is specifically targeted at an audience focused on featuring critical information and guidelines for developing polysaccharide-based coatings. Including such a complementary work in the journal could lead to further developments on polysaccharide antibacterial applications.

A Review of Chitosan and Chitosan Nanofiber: Preparation, Characterization, and Its Potential Applications

Chitosan is produced by deacetylating the abundant natural chitin polymer. It has been employed in a variety of applications due to its unique solubility as well as its chemical and biological properties. In addition to being biodegradable and biocompatible, it also possesses a lot of reactive amino side groups that allow for chemical modification and the creation of a wide range of useful derivatives. The physical and chemical characteristics of chitosan, as well as how it is used in the food, environmental, and medical industries, have all been covered in a number of academic publications. Chitosan offers a wide range of possibilities in environmentally friendly textile processes because of its superior absorption and biological characteristics. Chitosan has the ability to give textile fibers and fabrics antibacterial, antiviral, anti-odor, and other biological functions. One of the most well-known and frequently used methods to create nanofibers is electrospinning. This technique is adaptable and effective for creating continuous nanofibers. In the field of biomaterials, new materials include nanofibers made of chitosan. Numerous medications, including antibiotics, chemotherapeutic agents, proteins, and analgesics for inflammatory pain, have been successfully loaded onto electro-spun nanofibers, according to recent investigations. Chitosan nanofibers have several exceptional qualities that make them ideal for use in important pharmaceutical applications, such as tissue engineering, drug delivery systems, wound dressing, and enzyme immobilization. The preparation of chitosan nanofibers, followed by a discussion of the biocompatibility and degradation of chitosan nanofibers, followed by a description of how to load the drug into the nanofibers, are the first issues highlighted by this review of chitosan nanofibers in drug delivery applications. The main uses of chitosan nanofibers in drug delivery systems will be discussed last.

Effects of carboxymethyl cellulose on the emulsifying, gel and digestive properties of myofibrillar protein-soybean oil emulsion

Improving the qualities of vegetable oil replaced animal fat meat products is particularly fascinating for the development of healthy meat products. This work was designed to investigate the effects of different carboxymethyl cellulose (CMC) concentrations (0.01 %, 0.05 %, 0.1 %, 0.2 %, and 0.5 %) on the emulsifying, gelation, and digestive properties of myofibrillar protein (MP)-soybean oil emulsions. The changes in MP emulsion characteristics, gelation properties, protein digestibility, and oil release rate were determined. Results demonstrated that CMC addition decreased the average droplet size and increased the apparent viscosity, storage modulus, and loss modulus of MP emulsions, and a 0.5 % CMC addition significantly increased the storage stability during 6 weeks. Lower CMC addition (0.01 % to 0.1 %) increased the hardness, chewiness, and gumminess of emulsion gel especially for the 0.1 % CMC addition, while higher CMC (0.5 %) content decreased the texture properties and water holding capacity of emulsion gels. The addition of CMC decreased protein digestibility during the gastric stage, and 0.01 % and 0.05 % CMC addition significantly decreased the free fatty acid release rate. In summary, the addition of CMC could improve the stability of MP emulsion and the texture properties of the emulsion gels, and decrease protein digestibility during the gastric stage.

Biodegradable wound dressing-based collagen/hyaluronic acid loaded antibacterial agents for wound healing application

Three biodegradable wound dressing based on binary Collagen (COL), Hyaluronic acid (HA) crosslinked loaded with silver nanoparticles (AgNPs), Gentamicin (GENT) and AgNPs/GENT successfully prepared using freeze drying technique. Chemical evaluations for synthesized membranes were carried out using FTIR- ATR. While physical properties were evaluated through swelling and degradation percent. Antibacterial activity was evaluated against G+, G-, yeast and fungi. Finally, cytotoxicity and wound healing evaluations were carried out against skin fibroblast normal cell line, while anti-inflammatory evaluated using RAW 264.7 macrophage cell line. The three produced membrane showed physically interaction between polymer network and the loaded antibiotic. Swelling properties showed superior results for three membranes. Degradability of prepared sheets was rapidly no more than three days. Toxicity evaluations and anti-inflammatory showed superior results for all examined samples except mixed with AgNPs and Gentamicin (GENT). Antibacterial activity showed resistance to G+, G- and yeast. All prepared sheet showed safe towards cell except COL/HA/AgNPs/GENT. Wound healing studied showed efficient of both COL/HA/AgNPs and COL/HA/GENT compared to blank and mixed membrane COL/HA/AgNPs/GENT. The obtained results recommended COL/HA loaded individually either AgNPs or Gentamicin (GENT) as antibacterial and wound healing sheet rather than mixed prepared membrane.

An antibacterial and self-healing hydrogel from aldehyde-carrageenan for wound healing applications

This study aimed to develop and characterize a novel antibacterial, self-healing hydrogel made from aldehyde-carrageenan. Thus, carrageenan (CA) was first oxidized using different amounts of sodium periodate (NaIO₄), and the highest concentration of aldehyde was obtained when the ratio of NaIO₄ to CA was 1.5:1. Using dopamine (PDA) and zinc ions (Zn²⁺), various hydrogels were synthesized from oxidized carrageenan (O-CA). The effects of dopamine and zinc ions on the properties of O-CA hydrogel were examined. According to Fourier Transform Infrared Spectroscopy (FTIR) studies, the hydrogel's components are linked by Schiff bases, hydrogen bonds, and ion complexes. The rheological tests confirmed that hydrogels were elastic gels, not viscous sol, and were able to recover rapidly. Adding zinc to the hydrogel reduced weight loss (38 %) and provided extra antibacterial properties, particularly against E. coli. In addition, collagen secretion and cell attachment to Zn-containing hydrogels were significantly increased, and fibroblast viability reached 118 %. Overall, a hybrid O-CA/PDA/Zn hydrogel has excellent potential for wound healing applications.

Free Salt Dyeing by Treatment of Cotton Fabric Using Carboxyethyl Chitosan and Synthesized Direct Dyes to Enhance Dyeing Properties and Antibacterial Activity

AIM

The purpose of this paper is to synthesize and characterize two new direct dyes based on chromenes derivatives.

BACKGROUND

The synthesis of carboxyethyl chitosan (CECS) by the reaction of chitosan and acrylic acid via Michael's addition reaction was conducted. Cotton fabrics were treated with CECS to enhance the exhaustion of dye, fastness properties, and antimicrobial activity of dyed fabric.

METHODS

Chitosan (CS) and acrylic acid were combined in Michael's addition process to successfully produce N-carboxyethylchitosan (CECS). Then, the cotton was treated with different concentrations of carboxyethyl chitosan (0.5-5 wt.%) and then dyed by synthesized mono azo and diazo direct dyes based on chromene derivatives.

RESULTS AND DISCUSSION

The results regarding dyeing and antibacterial activity indicated highquality dyeing properties, However, direct dyes showed higher exhaustion and fixation values, fastness properties, and the colorimetric CIE L*a*b* C*h° data of the dyed cotton fabric.

CONCLUSION

Cotton fabrics treated with carboxyethyl chitosan and dyed with direct dyes were found to have higher antibacterial activity upon a concentration of 2.5 wt.%. In addition, the antibacterial activity towards Gram-positive bacteria was reported to be more than Gram-negative bacteria.

Hyaluronic acid-based nanofibers: Electrospun synthesis and their medical applications; recent developments and future perspective

Hyaluronan is a biodegradable, biopolymer that represents a major part of the extracellular matrix and has the potential to be fabricated in a fibrous form conjugated with other polymers via electrospinning. Unique physicochemical features such as viscoelasticity, conductivity, and biological activity mainly affected by molecular weight attracted the attention of biomedical researchers to utilize hyaluronan for designing novel HA-based nano-devices. Particularly HA-based nanofibers get focused on a diverse range of applications in medical like tissue implants for regeneration of damaged tissue or organ repair, wound dressings, and drug delivery carriers to treat various disorders. Currently, electrospinning represents an effective available method for designing highly porous, 3D, HA-based nanofibers with features similar to that of the extra-cellular matrix making them a promising candidate for designing advanced regenerative medicines. This review highlights the structural and physicochemical features of HA, recently cited protocols in literature for HA production via microbial fermentation with particular focus on electrospun fabrication of HA-based nanofibers and parameters affecting its synthesis, current progress in medical applications of these electrospun HA-based nanofibers, their limitations and future perspective about the potential of these HA-based nanofibers in medical field.

Production and application of biomaterials based on polyvinyl alcohol (PVA) as wound dressing: A mini review

The development of ideal wound dressing with excellent properties, such as exudate absorption capacity, drug release control ability, and increased wound healing, is currently a major requirement for wound healing. Polyvinyl alcohol (PVA) is a biodegradable semi-crystalline synthetic polymer that has been used in the field of biotechnology such as tissue regeneration, wound dressing, and drug delivery systems. In recent years, PVA-based wound dressing materials have received considerable attention due to their excellent properties such as biodegradability, biocompatibility, non-toxicity and low cost. PVA can be used as a wound dressing material to create the necessary moist wound environment, improve the physical properties of the dressing, and increase the wound healing rates. In addition, PVA can also be mixed with other organic and inorganic materials and can be used for drug delivery and wound healing. This review article addresses the role of biomaterials based on PVA mixed with other ingredients for wound dressing. It also focuses on its recent use in wound dressings as carriers of active substances.

Carrageenan-Based Compounds as Wound Healing Materials

The following review is focused on carrageenan, a heteroglycan-based substance that is a very significant wound healing biomaterial. Every biomaterial has advantages and weaknesses of its own, but these drawbacks are typically outweighed by combining the material in various ways with other substances. Carrageenans' key benefits include their water solubility, which enables them to keep the wound and periwound damp and absorb the wound exudate. They have low cytotoxicity, antimicrobial and antioxidant qualities, do not stick to the wound bed, and hence do not cause pain when removed from the wounded region. When combined with other materials, they can aid in hemostasis. This review emphasizes the advantages of using carrageenan for wound healing, including the use of several mixes that improve its properties.

Marine Biopolymers as Bioactive Functional Ingredients of Electrospun Nanofibrous Scaffolds for Biomedical Applications

Marine biopolymers, abundantly present in seaweeds and marine animals, feature diverse structures and functionalities, and possess a wide range of beneficial biological activities. Characterized by high biocompatibility and biodegradability, as well as unique physicochemical properties, marine biopolymers are attracting a constantly increasing interest for the development of advanced systems for applications in the biomedical field. The development of electrospinning offers an innovative technological platform for the production of nonwoven nanofibrous scaffolds with increased surface area, high encapsulation efficacy, intrinsic interconnectivity, and structural analogy to the natural extracellular matrix. Marine biopolymer-based electrospun nanofibrous scaffolds with multifunctional characteristics and tunable mechanical properties now attract significant attention for biomedical applications, such as tissue engineering, drug delivery, and wound healing. The present review, covering the literature up to the end of 2021, highlights the advancements in the development of marine biopolymer-based electrospun nanofibers for their utilization as cell proliferation scaffolds, bioadhesives, release modifiers, and wound dressings.

Synthesis and characterization of polystyrene with embedded silver nanoparticle nanofibers to utilize as antibacterial and wound healing biomaterial

Herein, silver nanoparticles (Ag) embedded in polystyrene (PS) nanofiber composites have been prepared by an electrospinning technique using N, N-dimethylformamide (DMF) as a solvent and safe reducing agent. Electrospinning of polystyrene (PS) solutions is conducted using different electrospinning parameters such as polymer concentration in the electrospinning solution; solution feed rate, and electrical field strength. Then silver nanoparticles (AgNPs) were embedded into PS nanofibers to obtain an AgNPs-PS nanofiber composite as a powerful, cheap, and nontoxic bioactive material. PS nanofibers and AgNPs-PS nanofibers composite were characterized by using thermogravimetric analysis (TGA), X-ray diffraction, and scanning electron microscopy (SEM). Also, AgNPs were characterized by UV-vis spectroscopy, transmission electron microscopy (TEM), and EDX analysis. Results showed that PS nanofibers were obtained with concentrations ranging from 10–30 wt.% in DMF solvent. Also, an AgNPs-PS nanofiber composite has been produced from its solutions by using DMF at the optimum value. The prepared AgNPs have a 21–40 nm particle size and a semi-spherical shape. In addition, the antibacterial activity of AgNPs-PS nanofibers towards both Gram-positive and Gram-negative bacteria has been increased. Therefore, this nanocomposite can be used as a powerful bioactive material in biomedical fields.