Fabrication of honey-loaded ethylcellulose/gum tragacanth nanofibers as an effective antibacterial wound dressing

Electrospun composite membranes of ethyl cellulose and MXene (Ti3C2Tx): Biocompatible platforms for enhanced drug delivery and antibacterial wound healing

Ethyl cellulose (EC), a degradable cellulose derivative, served as a primary component in membranes fabricated by electrospinning for in vitro drug delivery applications. An effective strategy to enhance drug release was incorporating high-surface-area nanomaterials into polymeric drug carriers, which facilitated drug attachment to both the polymer matrix and additive surfaces, promoting release. MXene (Ti3C2Tx) demonstrated promising potential in improving tensile mechanical properties, antibacterial activity, and curcumin (Cur) release performance of EC membrane. Compared to Cur-loaded EC/MXene membranes, the toughness of Cur-loaded EC-based carriers significantly increased by 53.58 %, reaching 3.821 kJ/m3. This composite membrane exhibited exceptional antibacterial efficacy, notably reducing Staphylococcus aureus colonies by 52.4 × 107 CFU/mL after 168 h, through the dilution spread plate method. Using MTT assay, the composite membrane demonstrated biocompatibility, as evidenced by >70 % viability of mouse fibroblast L929 cells with observable cell attachment after 168 h. Importantly, the EC/MXene membrane achieved a Cur release amount of 69.82 % compared to 7.11 % from Cur-loaded EC membranes within 168 h, representing a 62.71 % enhancement in Cur release. The EC/MXene composite membrane is a promising drug delivery candidate, particularly for Cur, by utilizing the sustainability of EC as the primary drug carrier component.

Tannic acid-reinforced soy protein/oxidized tragacanth gum-based multifunctional hemostatic film for regulation of wound healing

With recent advances in the field of tissue engineering, composite films with biocompatibility, antimicrobial properties, and wound healing properties have gained potential applications in the field of wound dressings. In this research work, composite films of soy protein (S)/oxidized tragacanth gum (G) were successfully made using the solution casting process. The metal-organic framework containing curcumin (MOF) with concentrations of 5 and 10 wt% and tannic acid (TA) with concentrations of 6 and 12 wt% were entered into the polymer film. Surface morphology with scanning electron microscope (FE-SEM), thermal stability, mechanical properties, chemical structure, antioxidant, water absorption, cell viability, antibacterial activity, and biodegradability of the prepared films were investigated in laboratory conditions. In addition, the toxicity of the films in the cell environment was investigated, and the results showed that cell growth and proliferation improved in the presence of the prepared films, especially films SG/MOF10/TA6 and SG/MOF10/TA12 due to the presence of TA and MOF containing curcumin. Also, the antibacterial activity of the films showed that the presence of tannic acid and curcumin in the structure of the films increases their ability against pathogens. According to the obtained results, the newly produced nanocomposite film (SG/MOF10/TA12) has a high potential to be used for wound dressing due to its favorable characteristics and was considered the optimal film.

Synthesis and in vitro evaluation of cross-linked tragacanthin nanofibers as implants for delivery of cisplatin to hepatocellular carcinoma

There is growing interest in the use of electrospun polymeric nanofibers in drug delivery systems due to their remarkable surface-to-volume ratio, which enhances the processes of drug loading, specific cell binding and proliferation. The preferred polymers for drug delivery must be biocompatible and biodegradable. Gum tragacanth is one of the materials of choice for drug delivery. This work aimed at cross-linking the tragacanthin, the water-soluble fraction of gum tragacanth, with glutaraldehyde, synthesis of the cross-linked nanofibers and evaluating their properties to encapsulate and deliver a drug using caffeine as a model drug in the first place. The nanofibers were then loaded with cisplatin and evaluated against HepG2 cell line. The drug-loaded nanofibers (dia. 0.841 μm) were prepared by electrospinning using glutaraldehyde as the cross-linker and glycerol as a plasticizer and characterized by scanning electron microscopy, Fourier transform-infrared spectroscopy, electronic spectroscopy, 1HNMR, powder X-ray diffraction analysis, and thermogravimetric analysis. They released the encapsulated drugs in a sustained manner at pH 7.4 over 4.5 days (∼275 h with ∼80 % release) following Higuchi (cisplatin) and Hixon-Crowell (caffeine) kinetics. In a cytotoxicity assay against HepG2 cell line the cisplatin-loaded nanofibers exhibited enhanced activity compared to that with the standard cisplatin and in the caspase activity assay it activated caspase 3 to a higher extent and 8 and 9 to double the extent (4-fold) of cisplatin, suggesting a higher apoptotic activity by the nanoformulation than the standard cisplatin. Thus, nanoformulation appeared to be a potential candidate for treating hepatocellular carcinoma as an implant.

Production and performance evaluation of chitosan/collagen/honey nanofibrous membranes for wound dressing applications

Persistent bacterial infections are the leading risk factor that complicates the healing of chronic wounds. In this work, we formulate mixtures of polyvinyl alcohol (P), chitosan (CH), collagen (C), and honey (H) to produce nanofibrous membranes with healing properties. The honey effect at concentrations of 0 % (PCH and PCHC), 5 % (PCHC-5H), 10 % (PCHC-10H), and 15 % (PCHC-15H) on the physicochemical, antibacterial, and biological properties of the developed nanofibers was investigated. Morphological analysis by SEM demonstrated that PCH and PCHC nanofibers had a uniform and homogeneous distribution on their surfaces. However, the increase in honey content increased the fiber diameter (118.11-420.10) and drastically reduced the porosity of the membranes (15.79-92.62 nm). The addition of honey reduces the water vapor transmission rate (WVTR) and the adsorption properties of the membranes. Mechanical tests revealed that nanofibers were more flexible and elastic when honey was added, specifically the PCHC-15H nanofibers with the lowest modulus of elasticity (15 MPa) and the highest elongation at break (220 %). Also, honey significantly improved the antibacterial efficiency of the nanofibers, mainly PCHC-15H nanofibers, which presented the best bacterial reduction rates against Staphylococcus aureus (59.84 %), Pseudomonas aeruginosa (47.27 %), Escherichia coli (65.07 %), and Listeria monocytogenes (49.58 %). In vitro tests with cell cultures suggest that nanofibers were not cytotoxic and exhibited excellent biocompatibility with human fibroblasts (HFb) and keratinocytes (HaCaT), since all treatments showed higher or similar cell viability as opposed to the cell control. Based on the findings, PVA-chitosan-collagen-honey nanofibrous membranes have promise as an antibacterial dressing substitute.

Current trend on preparation, characterization and biomedical applications of natural polysaccharide-based nanomaterial reinforcement hydrogels: A review

The tunable properties of hydrogels have led to their widespread use in various biomedical applications such as wound treatment, drug delivery, contact lenses, tissue engineering and 3D bioprinting. Among these applications, natural polysaccharide-based hydrogels, which are fabricated from materials like agarose, alginate, chitosan, hyaluronic acid, cellulose, pectin and chondroitin sulfate, stand out as preferred choices due to their biocompatibility and advantageous fabrication characteristics. Despite the inherent biocompatibility, polysaccharide-based hydrogels on their own tend to be weak in physiochemical and mechanical properties. Therefore, further reinforcement in the hydrogel is necessary to enhance its suitability for specific applications, ensuring optimal performance in diverse settings. Integrating nanomaterials into hydrogels has proven effective in improving the overall network and performance of the hydrogel. This approach also addresses the limitations associated with pure hydrogels. Next, an overview of recent trends in the fabrication and applications of hydrogels was presented. The characterization of hydrogels was further discussed, focusing specifically on the reinforcement achieved with various hydrogel materials used so far. Finally, a few challenges associated with hydrogels by using polysaccharide-based nanomaterial were also presented.

Co-Delivery of Dragon's Blood and Alkanna tinctoria Extracts Using Electrospun Nanofibers: In Vitro and In Vivo Wound Healing Evaluation in Diabetic Rat Model

The increasing prevalence of diabetic wounds presents a significant challenge due to the difficulty of natural healing and various obstacles. Dragon's blood (DB) and Alkanna tinctoria (AT) are well recognized for their potent healing abilities, which include potent antibacterial and anti-inflammatory activities. In this study, electrospun nanofibers (NFs) based on polyvinyl pyrrolidone (PVP) were co-loaded with both DB and AT, aiming to magnify their efficacy as wound-dressing applications for diabetic wound healing. The evaluation of these NFs as wound dressings was conducted using a streptozotocin-induced diabetic rat model. Electrospun NFs were prepared using the electrospinning of the PVP polymer, resulting in nanofibers with consistent, smooth surfaces. The loading capacity (LC) of AT and DB into NFs was 64.1 and 70.4 µg/mg, respectively, while in the co-loaded NFs, LC was 49.6 for AT and 57.2 µg/mg for DB. In addition, X-ray diffraction (XRD) revealed that DB and AT were amorphously dispersed within the NFs. The loaded NFs showed a dissolution time of 30 s in PBS (pH 7.4), which facilitated the release of AT and DB (25-38% after 10 min), followed by a complete release achieved after 180 min. The antibacterial evaluation demonstrated that the DB-AT mixture had potent activity against Pseudomonas aeruginosa (P. aeruginosa) and Staphylococcus aureus (S. aureus). Along with that, the DB-AT NFs showed effective growth inhibition for both P. aeruginosa and S. aureus compared to the control NFs. Moreover, wound healing was evaluated in vivo in diabetic Wistar rats over 14 days. The results revealed that the DB-AT NFs improved wound healing within 14 days significantly compared to the other groups. These results highlight the potential application of the developed DB-AT NFs in wound healing management, particularly in diabetic wounds.

Deciphering the crosstalk between inflammation and biofilm in chronic wound healing: Phytocompounds loaded bionanomaterials as therapeutics

In terms of the economics and public health, chronic wounds exert a significant detrimental impact on the health care system. Bacterial infections, which cause the formation of highly resistant biofilms that elude standard antibiotics, are the main cause of chronic, non-healing wounds. Numerous studies have shown that phytochemicals are effective in treating a variety of diseases, and traditional medicinal plants often include important chemical groups such alkaloids, phenolics, tannins, terpenes, steroids, flavonoids, glycosides, and fatty acids. These substances are essential for scavenging free radicals which helps in reducing inflammation, fending off infections, and hastening the healing of wounds. Bacterial species can survive in chronic wound conditions because biofilms employ quorum sensing as a communication technique which regulates the expression of virulence components. Fortunately, several phytochemicals have anti-QS characteristics that efficiently block QS pathways, prevent drug-resistant strains, and reduce biofilm development in chronic wounds. This review emphasizes the potential of phytocompounds as crucial agents for alleviating bacterial infections and promoting wound healing by reducing the inflammation in chronic wounds, exhibiting potential avenues for future therapeutic approaches to mitigate the healthcare burden provided by these challenging conditions.

Recent Progress and Trends in the Development of Electrospun and 3D Printed Polymeric-Based Materials to Overcome Antimicrobial Resistance (AMR)

Antimicrobial resistance (AMR) developed by microorganisms is considered one of the most critical public health issues worldwide. This problem is affecting the lives of millions of people and needs to be addressed promptly. Mainly, antibiotics are the substances that contribute to AMR in various strains of bacteria and other microorganisms, leading to infectious diseases that cannot be effectively treated. To avoid the use of antibiotics and similar drugs, several approaches have gained attention in the fields of materials science and engineering as well as pharmaceutics over the past five years. Our focus lies on the design and manufacture of polymeric-based materials capable of incorporating antimicrobial agents excluding the aforementioned substances. In this sense, two of the emerging techniques for materials fabrication, namely, electrospinning and 3D printing, have gained significant attraction. In this article, we provide a summary of the most important findings that contribute to the development of antimicrobial systems using these technologies to incorporate various types of nanomaterials, organic molecules, or natural compounds with the required property. Furthermore, we discuss and consider the challenges that lie ahead in this research field for the coming years.

Preparation and Characterization of a Novel Tragacanth Gum/Chitosan/Sr-Nano-Hydroxyapatite Composite Membrane

It is a great challenge to obtain an ideal guided bone regeneration (GBR) membrane. In this study, tragacanth gum (GT) was introduced into a chitosan/nano-hydroxyapatite (CS/n-HA) system. The effects of different component ratios and strontium-doped nano-hydroxyapatite (Sr-HA) on the physical-chemical properties and degradation behavior of the CS/Sr-n-HA/GT ternary composite membrane were investigated using Fourier transform infrared spectroscopy (FT-IR), X-ray diffraction (XRD), scanning electron microscopy (SEM), contact angle, electromechanical universal tester and in vitro soaking in simulated body fluid (SBF). The results showed that CS could be ionically crosslinked with GT through electrostatic interaction, and Sr-n-HA was loaded via hydrogen bond, which endowed the GT/CS/n-HA composite membrane with good tensile strength and hydrophilicity. In addition, the results of immersion in SBF in vitro showed that CS/n-HA/GT composite membranes had different degradation rates and good apatite deposition by investigating the changes in pH value, weight loss, water absorption ratio, SEM morphology observation and tensile strength reduction. All results revealed that the CS/Sr-n-HA/GT (6:2:2) ternary composite membrane possessed the strongest ionic crosslinking of GT and CS, which was expected to obtain more satisfactory GBR membranes, and this study will provide new applications of GT in the field of biomedical membranes.

A bilayer biocompatible polycaprolactone/zinc oxide/Capparis spinosa L. ethyl acetate extract/polylactic acid nanofibrous composite scaffold for novel wound dressing applications

Capparis spinosa L. (CSL) is used in traditional medicinal purposes for wound dressing because it contains natural phenolic and flavonoid active compounds. In the current study, a bilayer of biocompatible and mechanically stable nanofiber scaffolds with polycaprolactone (PCL)/zinc oxide and Capparis spinosa L. ethyl acetate extract (CSLE)/polylactic acid (PLA) layers was successfully prepared by an electrostatic spinning technique. Microstructural observations carried out by scanning electron microscopy (SEM) have shown that the nanofibers with a smooth surface are continuous and bead-free, and that the size distribution is uniform, with an average diameter of 314.15 nm. The results of careful observation further suggested that polymers in the nanofibers have excellent compatibility with drugs. The results of Fourier transform infrared (FTIR) spectroscopy suggested that CSLE and zinc oxide nanoparticles (ZnO) were successfully loaded in the nanofiber membranes. Water contact angle measurements revealed that the bilayer nanofiber membranes exhibited satisfactory wettability (outside layer, 130°; inner layer, 72.4°). Tensile testing showed that the bilayer PCL/ZnO-CSLE/PLA nanofibers remained unbroken until reaching 10.69 MPa, which is much higher than the tensile strengths of the individual layers or the individual components. Moreover, agar disk diffusion assessment confirmed that the bilayer nanofiber membranes obviously hindered bacterial growth. Cytotoxicity studies showed that the bilayer nanofiber membranes effectively accelerated cell proliferation. The investigated PCL/ZnO-CSLE/PLA bilayer nanofibers have potential for use as membranes for wound dressing applications.

A review on tragacanth gum: A promising natural polysaccharide in drug delivery and cell therapy

Tragacanth is an abundant natural gum extracted from wounds created in some plants and is dried for use in various applications from industry to biomedicines. It is a cost-effective and easily accessible polysaccharide with desirable biocompatibility and biodegradability, drawing much attention for use in new biomedical applications such as wound healing and tissue engineering. Moreover, this anionic polysaccharide with a highly branched structure has been used as an emulsifier and thickening agent in pharmaceutical applications. In the following, this gum has been interested as an appealing biomaterial for producing engineering tools in drug delivery. Furthermore, the biological properties of tragacanth gum have made it a favorable biomaterial in cell therapies, especially for bone tissue engineering. This review aims to discuss the recent studies on this natural gum as a potential carrier for different drugs and cells.

Antioxidant Biomaterials in Cutaneous Wound Healing and Tissue Regeneration: A Critical Review

Natural-based biomaterials play an important role in developing new products for medical applications, primarily in cutaneous injuries. A large panel of biomaterials with antioxidant properties has revealed an advancement in supporting and expediting tissue regeneration. However, their low bioavailability in preventing cellular oxidative stress through the delivery system limits their therapeutic activity at the injury site. The integration of antioxidant compounds in the implanted biomaterial should be able to maintain their antioxidant activity while facilitating skin tissue recovery. This review summarises the recent literature that reported the role of natural antioxidant-incorporated biomaterials in promoting skin wound healing and tissue regeneration, which is supported by evidence from in vitro, in vivo, and clinical studies. Antioxidant-based therapies for wound healing have shown promising evidence in numerous animal studies, even though clinical studies remain very limited. We also described the underlying mechanism of reactive oxygen species (ROS) generation and provided a comprehensive review of ROS-scavenging biomaterials found in the literature in the last six years.

PDDA/Honey Antibacterial Nanofiber Composites for Diabetic Wound-Healing: Preparation, Characterization, and In Vivo Studies

In this paper, Poly (diallyldimethylammonium chloride) (PDDA)/honey nanofiber wound dressing composites were prepared and their effects on the diabetic wound-healing was evaluated using in vivo experiments. The release of effective compounds and the solubility of nanofibers were controlled through the crosslinking process by glutaraldehyde. The crosslinked nanofibers (crosslinking time was 3 h) showed an absorption capacity at a maximum value of 989.54%. Interestingly, the resultant composites were able to prevent 99.9% of Staphylococcus aureus and Escherichia coli bacteria. Furthermore, effective compounds were continuously released from nanofibers for up to 125 h. In vivo evaluation indicated that the use of PDDA/honey (40/60) significantly enhanced wound-healing. On the day 14th, the average healing rate for samples covered by conventional gauze bandage, PDDA, PDDA/honey (50/50), and PDDA/honey (40/60) were 46.8 ± 0.2, 59.4 ± 0.1, 81.7 ± 0.3, and 94.3 ± 0.2, respectively. The prepared nanofibers accelerated the wound-healing process and reduced the acute and chronic inflammation. Hence, our PDDA/honey wound dressing composites open up new future treatment options for diabetic wound diseases.

Fabrication of antibacterial and biocompatible 3D printed Manuka-Gelatin based patch for wound healing applications

Development of multifunctional 3D patches with appropriate antibacterial and biocompatible properties is needed to deal with wound care regeneration. Combining gelatin-based hydrogel with a well-known natural antibacterial honey (Manuka honey, MH) in a 3D patch can provide improved printability and at the same time provide favourable biological effects that may be useful in regenerative wound treatment. In this study, an antibacterial Manuka-Gelatin 3D patches was developed by an extrusion-based printing process, with controlled porosity, high shape fidelity, and structural stability. It was demonstrated the antibacterial activity of Manuka-Gelatin 3D patches against both gram-positive bacteria (S. epidermidis and S. aureus) and gram-negative (E. coli), common in wound infection. The 3D Manuka-Gelatin base patches demonstrated antibacterial activity, and moreover enhanced the proliferation of human dermal fibroblasts and human epidermal keratinocytes, and promotion of angiogenesis. Moreover, the ease of printing achieved by the addition of honey, coupled with the interesting biological response obtained, makes this 3D patch a good candidate for wound healing applications.

Investigation of wound healing efficiency of multifunctional eudragit/soy protein isolate electrospun nanofiber incorporated with ZnO loaded halloysite nanotubes and allantoin

One significant aspect of the current therapeutic agents employed in wound healing involves the engineering of nano polymeric scaffolds to mimic the properties of extracellular matrix (ECM). The present work aimed to prepare and evaluate Eudragit® L100 (EU) nanofibers in combination with soy protein isolate (SPI). Allantoin (Ala) with a 2 wt% was encapsulated as a model drug renowned for its anti-inflammatory and antioxidant agents. Moreover, the synthesized ZnO-halloysite nanotubes (ZHNTs) with different concentrations of 1, 3, and 5 wt% were incorporated into the EU/SPI/Ala nanofiber as a reinforcing filler and a remarkable antibacterial agent. The scanning electron microscope (SEM) analysis showed that by increasing the weight percentage of SPI from 1 % to 2.5 %, the average diameter of nanofibers decreased from 132.3 ± 51.3 nm to 126.7 ± 47.2 nm. It was 223.5 ± 95.6 nm for nanofibers containing 5 wt% ZHNTs (the optimal sample). The evaluation of in vitro release kinetics of Ala for 24 h, showed a burst release during the first 2 h and a sustained release during the subsequent times. Moreover, the structure, crystallinity, and thermal stability of synthesized nanofibers were characterized by Fourier Transform Infrared Spectrometry (FTIR), X-ray diffraction (XRD), and Thermo gravimetric analysis (TGA), respectively. In vitro degradation and mechanical characteristics of these nanofibers were studied. Furthermore, the capability of the nanofibers for cell proliferation was revealed through the MTT test and field emission scanning electron microscopy (FESEM) images of cell attachment. The antimicrobial activity of EU/SPI/Ala/ZHNTs showed that this sample with high ZHNTs content (5 w%t) had the most remarkable antibacterial activity against S. aureus. The results revealed that EU/SPI/Ala/ZHNTs mats could be promising potential wound dressings.

Honey-Loaded Reinforced Film Based on Bacterial Nanocellulose/Gelatin/Guar Gum as an Effective Antibacterial Wound Dressing

Recently, the use of bacterial nanocellulose (BNC) produced by Acetobacter, which has suitable properties for tissue engineering application as a perfect wound dressing, has attracted considerable attention. For this purpose, we successfully developed honey loaded BNC-reinforced gelatin/dialdehyde-modified guar gum films (H/BNC/Ge/D-GG). Prepared films were studied for their morphological, thermal stability, mechanical, water solubility and degradability properties. The physicochemical properties of the developed films with or without honey loading were studied. The results indicated that by enhancing the honey content of the film, the degradation behavior, adhesion and proliferation of NIH-3T3 fibroblast cells were improved. The films with 15 wt% of honey revealed inhibition activity against S. aureus (13.0±0.1 mm) and E. coli (15.0±1.0 mm) bacteria. Cell culture results demonstrated that the prepared films had good cytocompatibility. Based on the results, the prepared H/BNC/Ge/D-GG films appear to have high potential for antibacterial wound dressings.

Recent Advances in Honey-Based Nanoparticles for Wound Dressing: A Review

Wounds with impaired healing, including delayed acute injuries and chronic injuries, generally fail to progress through normal healing stages. A deeper understanding of the biochemical processes involved in chronic wound cures is necessary to correct the microenvironmental imbalances in the wound treatment designs of products. The therapeutic benefits of honey, particularly its antimicrobial activity, make it a viable option for wound treatment in a variety of situations. Integration with nanotechnology has opened up new possibilities not only for wound healing but also for other medicinal applications. In this review, recent advances in honey-based nanoparticles for wound healing are discussed. This also covers the mechanism of the action of nanoparticles in the wound healing process and perspectives on the challenges and future trends of using honey-based nanoparticles. The underlying mechanisms of wound healing using honey are believed to be attributed to hydrogen peroxide, high osmolality, acidity, non-peroxide components, and phenols. Therefore, incorporating honey into various wound dressings has become a major trend due to the increasing demand for combination dressings in the global wound dressing market because these dressings contain two or more types of chemical and physical properties to ensure optimal functionality. At the same time, their multiple features (low cost, biocompatibility, and swelling index) and diverse fabrication methods (electrospun fibres, hydrogels, etc.) make them a popular choice among researchers.

Novel Technologies in Chronic Wound Care

In Israel, 20% of wounds do not progress to full healing under treatment with conservative technologies of which 1 to 2% are eventually defined as chronic wounds. Chronic wounds are a complex health burden for patients and pose considerable therapeutic and budgetary burden on health systems. The causes of chronic wounds include systemic and local factors. Initial treatment involves the usual therapeutic means, but as healing does not progress, more advanced therapeutic technologies are used. Undoubtedly, advanced means, such as negative pressure systems, and advanced technologies, such as oxygen systems and micrografts, have vastly improved the treatment of chronic wounds. Our service specializes in treating ulcers and difficult-to-heal wounds while providing a multiprofessional medical response. Herein, we present our experience and protocols in treating chronic wounds using a variety of advanced dressings and technologies.

An Overview on the Recent Advances in the Treatment of Infected Wounds: Antibacterial Wound Dressings

A wound can be surgical, cuts from an operation or due to accident and trauma. The infected wound, as a result of bacteria growth within the damaged skin, interrupts the natural wound healing process and significantly impacts the quality of life. Wound dressing is an important segment of the skincare industry with its economic burden estimated at $ 20.4 billion (in 2021) in the global market. The results of recent clinical trials suggest that the use of modern dressings can be the easiest, most accessible, and most cost-effective way to treat chronic wounds and, hence, holds significant promise. With the sheer number of dressings in the market, the selection of correct dressing is confusing for clinicians and healthcare workers. The aim of this research was to review widely used types of antibacterial wound dressings, as well as emerging products, for their efficiency and mode of action. In this review, we focus on introducing antibiotics and antibacterial nanoparticles as two important and clinically widely used categories of antibacterial agents. The perspectives and challenges for paving the way for future research in this field are also discussed. This article is protected by copyright. All rights reserved.

Advances in Nanostructures for Antimicrobial Therapy

Microbial infections caused by a variety of drug-resistant microorganisms are more common, but there are fewer and fewer approved new antimicrobial chemotherapeutics for systemic administration capable of acting against these resistant infectious pathogens. Formulation innovations of existing drugs are gaining prominence, while the application of nanotechnologies is a useful alternative for improving/increasing the effect of existing antimicrobial drugs. Nanomaterials represent one of the possible strategies to address this unfortunate situation. This review aims to summarize the most current results of nanoformulations of antibiotics and antibacterial active nanomaterials. Nanoformulations of antimicrobial peptides, synergistic combinations of antimicrobial-active agents with nitric oxide donors or combinations of small organic molecules or polymers with metals, metal oxides or metalloids are discussed as well. The mechanisms of actions of selected nanoformulations, including systems with magnetic, photothermal or photodynamic effects, are briefly described.

An Overview of Cellulose Derivatives-Based Dressings for Wound-Healing Management

Presently, notwithstanding the progress regarding wound-healing management, the treatment of the majority of skin lesions still represents a serious challenge for biomedical and pharmaceutical industries. Thus, the attention of the researchers has turned to the development of novel materials based on cellulose derivatives. Cellulose derivatives are semi-synthetic biopolymers, which exhibit high solubility in water and represent an advantageous alternative to water-insoluble cellulose. These biopolymers possess excellent properties, such as biocompatibility, biodegradability, sustainability, non-toxicity, non-immunogenicity, thermo-gelling behavior, mechanical strength, abundance, low costs, antibacterial effect, and high hydrophilicity. They have an efficient ability to absorb and retain a large quantity of wound exudates in the interstitial sites of their networks and can maintain optimal local moisture. Cellulose derivatives also represent a proper scaffold to incorporate various bioactive agents with beneficial therapeutic effects on skin tissue restoration. Due to these suitable and versatile characteristics, cellulose derivatives are attractive and captivating materials for wound-healing applications. This review presents an extensive overview of recent research regarding promising cellulose derivatives-based materials for the development of multiple biomedical and pharmaceutical applications, such as wound dressings, drug delivery devices, and tissue engineering.