Preparation Of Wound Dressings Research Articles

Bioactive Curcuma aromatica-stabilized silver nanoparticles embedded chitosan dressing with improved antibacterial, anti-inflammatory, and wound healing properties

Chronic wounds, particularly those infected with multidrug-resistant (MDR) pathogens, present significant challenges for effective healing. Silver nanoparticles (CAAgNPs) were synthsized using aqueous rhizome extract of Curcuma aromatica (CA), known for its wound-healing properties. CAAgNPs were incorporated in a chitosan (CS) dressing (CAAgNPs/CS) and tested for their wound healing potential, expecting synergistic action of AgNPs and phytochemicals capped on it. The porous nature of the CAAgNPs was confirmed using Field emission scanning electron microscopy. Fourier-transform infrared spectroscopy demonstrated a shift in peak intensity from 1589.06 to 1575.54 cm-1 for CAAgNPs/CS dressing confirming crosslinking with glutaraldehyde. Antibacterial activity of the dressings was cofirmed against isolates of Pseudomonas aeruginosa and Staphylococcus aureus. Wound healing studies were carried out using Wistar rats (six groups)- wound control, CS, CAAgNPs256/CS, CAAgNPs512/CS, CAAgNPs1024/CS, and commercial dressings. Histological examination and direct red-80 staining demonstrated maximum epithelization and collagen deposition (58.02%) within CAAgNPs1024/CS groups on day 10. Increased hydroxyproline levels (76.51 µg/mL) on day 7 for CAAgNPs1024/CS indicated maximum collagen formation. Reduced levels of inflammatory cytokines IL-6 (17.38 pg/mL) and TNF-α (80.38 pg/mL) on day 10 indicated quick wound healing without scar formation and damaging effects. The present study highlights the antibacterial and anti-inflammatory properties of CAAgNPs1024/CS dressings with a potential for wound healing applications.

Bletilla striata Polysaccharide-/Chitosan-Based Self-Healing Hydrogel with Enhanced Photothermal Effect for Rapid Healing of Diabetic Infected Wounds via the Regulation of Microenvironment.

The management of diabetic ulcers poses a significant challenge worldwide, and persistent hyperglycemia makes patients susceptible to bacterial infections. Unfortunately, the overuse of antibiotics may lead to drug resistance and prolonged infections, contributing to chronic inflammation and hindering the healing process. To address these issues, a photothermal therapy technique was incorporated in the preparation of wound dressings. This innovative solution involved the formulation of a self-healing and injectable hydrogel matrix based on the Schiff base structure formed between the oxidized Bletilla striata polysaccharide (BSP) and hydroxypropyltrimethylammonium chloride chitosan. Furthermore, the introduction of CuO nanoparticles encapsulated in polydopamine imparted excellent photothermal properties to the hydrogel, which promoted the release of berberine (BER) loaded on the nanoparticles and boosted the antibacterial performance. In addition to providing a reliable physical protection to the wound, the developed hydrogel, which integrated the herbal components of BSP and BER, effectively accelerated wound closure via microenvironment regulation, including alleviated inflammatory reaction, stimulated re-epithelialization, and reduced oxidative stress based on the promising results from cell and animal experiments. These impressive outcomes highlighted their clinical potential in safeguarding the wound against bacterial intrusion and managing diabetic ulcers.

Bacterial nanocelullose in biomedical applications: a review

AbstractThis review reports recent advances in the application of bacterial nanocellulose (BNC) in biomedical fields. BNC has attracted both academic and industrial attention as it shows interesting properties for both biomedical and cosmetic applications. Herein, the structure, properties and selected applications of BNC in the preparation of wound dressings and artificial skin are discussed in general, and detailed examples are also drawn from the scientific literature. In this review the most common applications are presented in detail together with issues related to regenerative medicine and biomedicine, skin tissue engineering, auricular cartilage reconstruction, bone regeneration and the treatment of traumatic tympanic membrane perforation. © 2019 Society of Chemical Industry

A novel gentamicin-releasing wound dressing prepared from freshwater fish Cyprinus carpio collagen cross-linked with carbodiimide

Our study presents a novel collagen wound dressing prepared from freshwater fish skin ( Cyprinus Carpio) collagen type I. Half of the sponges were cross-linked with carbodiimide. The cross-linked and non-cross-linked collagen sponges were subsequently impregnated with gentamicin and lyophilized thus allowing for the attainment of the appropriate gentamicin content without the removal thereof during the cross-linking stage. The structure was evaluated via micro-CT and infrared spectrometry and the structural stability and gentamicin release properties were evaluated in phosphate buffer solution. The sponges were further tested via a rat model of an infected wound with Pseudomonas aeruginosa inoculation and compared with a reference commercial product. The sponges thus prepared provided a degree of open porosity that was comparable to or higher than that of the reference commercial product. Spectrometry analysis revealed that the cross-linked collagen sponge and reference commercial product sponge preserved their secondary collagen structure after 168 h while early accelerated degradation was observed with respect to the non-cross-linked collagen sponge. Gentamicin was released rapidly from all the sponges. Compared to those animals with gentamicin-containing sponges or gentamicin administered intramuscularly, the animals with the cross-linked collagen sponge without gentamicin exhibited marked clinical and laboratory infection signs. Both the administration routes (intramuscular and via gentamicin-containing sponges) provided similar gentamicin plasma levels. The resulting highly homogeneous product which was characterized by excellent structural and clinical properties proved effective in terms of the treatment of a surgical wound infection in a rat model. We demonstrated that all the gentamicin was released from the sponge and was absorbed in the systemic circulation. This is the first time that Cyprinus Carpio collagen has been used in the preparation of wound dressings. Thus, gentamicin-containing sponges provide a promising tool for the treatment and prevention of surgical site infections.

Human neutrophil elastase and collagenase sequestration with phosphorylated cotton wound dressings

The design and preparation of wound dressings that redress the protease imbalance in chronic wounds is an important goal of wound healing and medical materials science. Chronic wounds contain high levels of tissue and cytokine-destroying proteases including matrix metalloprotease and neutrophil elastase. Thus, the lowering of excessive protease levels in the wound environment by wound dressing sequestration prevents the breakdown of extracellular matrix proteins and growth factors necessary for wound healing. Phosphorylated cotton wound dressings were prepared to target sequestration of proteases from chronic wound exudate through a cationic uptake binding mechanism involving salt bridge formation of the positively charged amino acid side chains of proteases with the phosphate counterions of the wound dressing fiber. Dressings were prepared by applying sodium hexametaphosphate and diammonium phosphate in separate formulations to cotton gauze by pad/dry/cure methods. Phosphorylated cotton dressings were assessed for their ability to lower elastase and collagenase activity. The phosphorylated cotton dressings lowered elastase and collagenase activity 40-80% more effectively than the untreated cotton wound dressings under conditions that mimic chronic wound exudate. Efficacy of the phosphorylated cotton was found to be related to the level of phosphorylation and a lower pH due to protonated phosphate at the surface of the dressing. The capacity of the modified gauze to sequester continued elastase secretions similar to that found in a chronic wound over a 24-h period was retained within a 80% retention of elastase sequestration and was dose-dependent.