Double membrane based on lidocaine-coated polymyxin-alginate nanoparticles for wound healing: In vitro characterization and in vivo tissue repair

Biopolymer based nanoparticles and their therapeutic potential in wound healing - A review

Nanoparticles (NPs) have been extensively investigated for their potential in nanomedicine. There is a significant level of enthusiasm about the potential of NPs to bring out a transformative impact on modern healthcare. NPs can serve as effective wound dressings or delivery vehicles due to their antibacterial and pro-wound-healing properties. Biopolymer-based NPs can be manufactured using various food-grade biopolymers, such as proteins, polysaccharides, and synthetic polymers, each offering distinct properties suitable for different applications which include collagen, polycaprolactone, chitosan, alginate, and polylactic acid, etc. Their biodegradable and biocompatible nature renders them ideal nanomaterials for applications in wound healing. Additionally, the nanofibers containing biopolymer-based NPs have shown excellent anti-bacterial and wound healing activity like silver NPs. These NPs represent a paradigm shift in wound healing therapies, offering targeted and personalized solutions for enhanced tissue regeneration and accelerated wound closure. The current review focuses on biopolymer NPs with their applications in wound healing.

Chitosan Hydrogel as Tissue Engineering Scaffolds for Vascular Regeneration Applications

Chitosan hydrogels have a wide range of applications in tissue engineering scaffolds, mainly due to the advantages of their chemical and physical properties. This review focuses on the application of chitosan hydrogels in tissue engineering scaffolds for vascular regeneration. We have mainly introduced these following aspects: advantages and progress of chitosan hydrogels in vascular regeneration hydrogels and the modification of chitosan hydrogels to improve the application in vascular regeneration. Finally, this paper discusses the prospects of chitosan hydrogels for vascular regeneration.

Alginate-Based Materials Loaded with Nanoparticles in Wound Healing

Alginate is a naturally derived polysaccharide widely applied in drug delivery, as well as regenerative medicine, tissue engineering and wound care. Due to its excellent biocompatibility, low toxicity, and the ability to absorb a high amount of exudate, it is widely used in modern wound dressings. Numerous studies indicate that alginate applied in wound care can be enhanced with the incorporation of nanoparticles, revealing additional properties beneficial in the healing process. Among the most extensively explored materials, composite dressings with alginate loaded with antimicrobial inorganic nanoparticles can be mentioned. However, other types of nanoparticles with antibiotics, growth factors, and other active ingredients are also investigated. This review article focuses on the most recent findings regarding novel alginate-based materials loaded with nanoparticles and their applicability as wound dressings, with special attention paid to the materials of potential use in the treatment of chronic wounds.

Biodegradable Biopolymeric Nanoparticles for Biomedical Applications-Challenges and Future Outlook

Biopolymers are polymers obtained from either renewable or non-renewable sources and are the most suitable candidate for tailor-made nanoparticles owing to their biocompatibility, biodegradability, low toxicity and immunogenicity. Biopolymeric nanoparticles (BPn) can be classified as natural (polysaccharide and protein based) and synthetic on the basis of their origin. They have been gaining wide interest in biomedical applications such as tissue engineering, drug delivery, imaging and cancer therapy. BPn can be synthesized by various fabrication strategies such as emulsification, ionic gelation, nanoprecipitation, electrospray drying and so on. The main aim of the review is to understand the use of nanoparticles obtained from biodegradable biopolymers for various biomedical applications. There are very few reviews highlighting biopolymeric nanoparticles employed for medical applications; this review is an attempt to explore the possibilities of using these materials for various biomedical applications. This review highlights protein based (albumin, gelatin, collagen, silk fibroin); polysaccharide based (chitosan, starch, alginate, dextran) and synthetic (Poly lactic acid, Poly vinyl alcohol, Poly caprolactone) BPn that has recently been used in many applications. The fabrication strategies of different BPn are also being highlighted. The future perspective and the challenges faced in employing biopolymeric nanoparticles are also reviewed.

Monoolein-based nanodispersions for cutaneous co-delivery of methylene blue and metformin: Thermal and structural characterization and effects on the cutaneous barrier, skin penetration and cytotoxicity

This study evaluated the potential of monoolein (MO)-based nanodispersions to promote the cutaneous co-delivery of metformin (MET) and methylene blue (MB) for the treatment of non-melanoma skin cancer. MO-based nanodispersions were obtained using Kolliphor® P407 (KP) and/or sodium cholate (CH), and characterized concerning the structure, thermal stability, ability to disrupt the skin barrier, cutaneous permeation and retention of MB and MET. Additionally, the cytotoxic effect of MO nanodispersions-mediated combination therapy using MET and MB in A431 cells was evaluated. The nanodispersions exhibited nanometric size (<200 nm) and thermal and physical stability. Small angle X-ray scattering studies revealed multiple structures depending on composition. They were able to interact with stratum corneum lipid structure, increasing its fluidity. The effect of MO-nanodispersions on topical/transdermal delivery of MB and MET was composition-dependent. Nanodispersions with low MO content (5 %) and stabilized with KP and CH (0.05-0.10 %) were the most promising, enhancing the cutaneous delivery of MB and MET by 1.9 to 2.2-fold and 1.4 to 1.7-fold, respectively, compared to control. Cytotoxic studies revealed that the most promising MO nanodispersion-mediated combination therapy using MET and MB (1:1) reduced the IC₅₀ by 24-fold, compared to MB solution, and a further reduction (1.5-fold) was observed by MB photoactivation.

Cutaneous/Mucocutaneous Leishmaniasis Treatment for Wound Healing: Classical versus New Treatment Approaches

Cutaneous leishmaniasis (CL) and mucocutaneous leishmaniasis (ML) show clinical spectra that can range from a localized lesion (with a spontaneous healing process) to cases that progress to a generalized systemic disease with a risk of death. The treatment of leishmaniasis is complex since most of the available drugs show high toxicity. The development of an effective topical drug formulation for CL and ML treatment offers advantages as it will improve patient’s compliance to the therapy given the possibility for self-administration, as well as overcoming the first pass metabolism and the high costs of currently available alternatives. The most common dosage forms include solid formulations, such as membranes and semi-solid formulations (e.g., ointments, creams, gels, and pastes). Topical treatment has been used as a new route of administration for conventional drugs against leishmaniasis and its combinations, as well as to exploit new substances. In this review, we discuss the advantages and limitations of using topical drug delivery for the treatment of these two forms of leishmaniasis and the relevance of combining this approach with other pharmaceutical dosage forms. Emphasis will also be given to the use of nanomaterials for site-specific delivery.

Immobilization Systems of Antimicrobial Peptide Ib−M1 in Polymeric Nanoparticles Based on Alginate and Chitosan

The development of new strategies to reduce the use of traditional antibiotics has been a topic of global interest due to the resistance generated by multiresistant microorganisms, including Escherichia coli, as etiological agents of various diseases. Antimicrobial peptides are presented as an alternative for the treatment of infectious diseases caused by this type of microorganism. The Ib−M1 peptide meets the requirements to be used as an antimicrobial compound. However, it is necessary to use strategies that generate protection and resist the conditions encountered in a biological system. Therefore, in this study, we synthesized alginate and chitosan nanoparticles (Alg−Chi NPs) using the ionic gelation technique, which allows for the crosslinking of polymeric chains arranged in nanostructures by intermolecular interactions that can be either covalent or non-covalent. Such interactions can be achieved through the use of crosslinking agents that facilitate this binding. This technique allows for immobilization of the Ib−M1 peptide to form an Ib−M1/Alg−Chi bioconjugate. SEM, DLS, and FT-IR were used to determine the structural features of the nanoparticles. We evaluated the biological activity against E. coli ATCC 25922 and Vero mammalian cells, as well as the stability at various temperatures, pH, and proteases, of Ib−M1 and Ib−M1/Alg-Chi. The results showed agglomerates of nanoparticles with average sizes of 150 nm; an MIC of 12.5 µM, which was maintained in the bioconjugate; and cytotoxicity values close to 40%. Stability was maintained against pH and temperature; in proteases, it was only evidenced against pepsin in Ib−M1/Alg-Chi. The results are promising with respect to the use of Ib−M1 and Ib−M1/Alg−Chi as possible antimicrobial agents.

Cashew Gum: A Review of Brazilian Patents and Pharmaceutical Applications with a Special Focus on Nanoparticles

Natural polysaccharides are structures composed of highly diversified biological macromolecules whose properties have been exploited by a diversity of industries. Until 2018, the polysaccharides market raised more than US $ 12 billion worldwide, while an annual growth forecast of 4.8% is expected by 2026. The food industry is largely responsible for the consumption of this plant-source material, produced by microbiological fermentation. Among the used polysaccharides, gums are hydrocolloids obtained from a variety of sources and in different forms, being composed of salts of calcium, potassium, magnesium and sugar monomers. Their non-toxicity, hydrophilicity, viscosity, biodegradability, biocompatibility and sustainable production are among their main advantages. Although Brazil is amongst the largest producers of cashew gum, reaching 50 tons per year, the polysaccharide is not being used to its full potential, in particular, with regard to its uses in pharmaceuticals. Cashew gum (CG), obtained from Anacardium occidentale L., caught the attention of the industry only in 1970; in 1990, its production started to grow. Within the Brazilian academy, the groups from the Federal University of Ceará and Piauí are devoting the most efforts to the study of cashew gum, with a total of 31 articles already published. The number of patents in the country for innovations containing cashew tree gum has reached 14, including the technological process for the purification of cashew tree gum, comparison of physical and chemical methods for physicochemical characterizations, and optimum purification methodology. This scenario opens a range of opportunities for the use of cashew gum, mainly in the development of new pharmaceutical products, with a special interest in nanoparticles.

How Effective are Nano-Based Dressings in Diabetic Wound Healing? A Comprehensive Review of Literature

Chronic wound caused by diabetes is an important cause of disability and seriously affects the quality of life of patients. Therefore, it is of great clinical significance to develop a wound dressing that can accelerate the healing of diabetic wounds. Nanoparticles have great advantages in promoting diabetic wound healing due to their antibacterial properties, low cytotoxicity, good biocompatibility and drug delivery ability. Adding nanoparticles to the dressing matrix and using nanoparticles to deliver drugs and cytokines to promote wound healing has proven to be effective. This review will focus on the effects of diabetes on wound healing, introduce the properties, preparation methods and action mechanism of nanoparticles in wound healing, and describe the effects and application status of various nanoparticle-loaded dressings in diabetes-related chronic wound healing.

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.

Biosurfactants: Properties and Applications in Drug Delivery, Biotechnology and Ecotoxicology

Surfactants are amphiphilic compounds having hydrophilic and hydrophobic moieties in their structure. They can be of synthetic or of microbial origin, obtained respectively from chemical synthesis or from microorganisms’ activity. A new generation of ecofriendly surfactant molecules or biobased surfactants is increasingly growing, attributed to their versatility of applications. Surfactants can be used as drug delivery systems for a range of molecules given their capacity to create micelles which can promote the encapsulation of bioactives of pharmaceutical interest; besides, these assemblies can also show antimicrobial properties. The advantages of biosurfactants include their high biodegradability profile, low risk of toxicity, production from renewable sources, functionality under extreme pH and temperature conditions, and long-term physicochemical stability. The application potential of these types of polymers is related to their properties enabling them to be processed by emulsification, separation, solubilization, surface (interfacial) tension, and adsorption for the production of a range of drug delivery systems. Biosurfactants have been employed as a drug delivery system to improve the bioavailability of a good number of drugs that exhibit low aqueous solubility. The great potential of these molecules is related to their auto assembly and emulsification capacity. Biosurfactants produced from bacteria are of particular interest due to their antibacterial, antifungal, and antiviral properties with therapeutic and biomedical potential. In this review, we discuss recent advances and perspectives of biosurfactants with antimicrobial properties and how they can be used as structures to develop semisolid hydrogels for drug delivery, in environmental bioremediation, in biotechnology for the reduction of production costs and also their ecotoxicological impact as pesticide alternative.

Lipid-Polymeric Films: Composition, Production and Applications in Wound Healing and Skin Repair

The use of lipids in the composition of polymeric-based films for topical administration of bioactive ingredients is a recent research topic; while few products are commercially available, films containing lipids represent a strategic area for the development of new products. Some lipids are usually used in polymeric-based film formulations due to their plasticizing action, with a view to improving the mechanical properties of these films. On the other hand, many lipids have healing, antimicrobial, anti-inflammatory, anti-aging properties, among others, that make them even more interesting for application in the medical-pharmaceutical field. This manuscript discusses the production methods of these films both on a laboratory and at industrial scales, the properties of the developed biopolymers, and their advantages for the development of dermatologic and cosmetic products.

Histological Evidence of Wound Healing Improvement in Rats Treated with Oral Administration of Hydroalcoholic Extract of Vitis labrusca

Plant extracts rich in phenolic compounds have been demonstrated to accelerate wound healing, but their use by oral route has been poorly studied. The leaves of Vitis labrusca are rich in phenolic acids and flavonoids. The goal of this study was to assess the healing properties of the oral administration of hydroalcoholic extract of V. labrusca leaves (HEVL) in a murine model. HEVL was obtained by Soxhlet and dynamic maceration, and their yield and phenolic acids and flavonoid contents were determined. For the wound healing assay, 8 mm wounds were performed on the back of 48 Wistar rats, assigned into four groups (n = 12): CTR (distilled water), HEVL100, HEVL200, and HEVL300 (HEVL at 100, 200, and 300 mg/kg, respectively). On days 7 and 14, wound closure rates were assessed, and the healing wounds were subjected to histological analysis. Soxhlet-obtained extract was selected for the wound healing assay because it provided a higher yield and phenolic acid and flavonoid contents. HEVL significantly reduced leukocytosis in the peripheral blood (p < 0.05), accelerated wound closure (p < 0.05), and improved collagenization (p < 0.05) on day 7, as well as enhanced the epidermal tissue thickness (p < 0.001) and elastic fiber deposition on day 14 (p < 0.01). Furthermore, HEVL promoted an increase in the histological grading of wound healing on both days 7 and 14 (p < 0.01). The doses of 200 and 300 mg/kg provided better results than 100 mg/Kg. Our data provide histological evidence that the oral administration of HEVL improves wound healing in rodents. Therefore, the extract can be a potential oral medicine for healing purposes.

The Potential Role of Polyelectrolyte Complex Nanoparticles Based on Cashew Gum, Tripolyphosphate and Chitosan for the Loading of Insulin

Polyelectrolytic complexation has stood out due to its application in the development of drug delivery systems using biopolymers as raw materials. The formation of complexes between cashew gum and chitosan can be intermediated by cross-links, mediated by the action of the sodium tripolyphosphate crosslinking agent. These polymers have been used in the nanotechnological development of formulations to protect peptide drugs, such as insulin, allowing their oral administration. In this work, we describe the development of polyelectrolytic complexes from cashew gum and chitosan as biopolymers for oral administration of insulin. The obtained complexes showed a mean particle size of 234 nm and polydispersity index of 0.2. The complexes were 234 nm in size, PDI 0.2, zeta potential −4.5 mV and 22% trapping. The obtained complexes demonstrated considerable and promising characteristics for use as oral insulin delivery systems.

Sustained dual release of ciprofloxacin and lidocaine from ionic exchange responding film based on alginate and hyaluronate for wound healing

This study presents a new antibiotic-anesthetic film (AA-film) based on natural polyelectrolytes ionically complexed with lidocaine and ciprofloxacin to manage pain associated with infected wounds. The rational selection of the components resulted in the AA-films being transparent, compatible with wound skin pH and highly water vapor permeable. The drug release properties evaluated in saline solution and water revealed an ionic exchange mechanism for the release of both drugs and showed that ciprofloxacin acts as a cross-linker, as was confirmed by rheological evaluation. The in vitro antimicrobial efficacy against S. aureus and P. aeruginosa was demonstrated. Furthermore, AA-films exhibit a high fluid absorption capacity and act as a physical barrier for microorganisms. This work highlights the great potential of this smart system as an attractive dressing for skin wounds, surpassing currently available treatments.

Polymeric Nanoparticles for Antimicrobial Therapies: An Up-To-Date Overview

Despite the many advancements in the pharmaceutical and medical fields and the development of numerous antimicrobial drugs aimed to suppress and destroy pathogenic microorganisms, infectious diseases still represent a major health threat affecting millions of lives daily. In addition to the limitations of antimicrobial drugs associated with low transportation rate, water solubility, oral bioavailability and stability, inefficient drug targeting, considerable toxicity, and limited patient compliance, the major cause for their inefficiency is the antimicrobial resistance of microorganisms. In this context, the risk of a pre-antibiotic era is a real possibility. For this reason, the research focus has shifted toward the discovery and development of novel and alternative antimicrobial agents that could overcome the challenges associated with conventional drugs. Nanotechnology is a possible alternative, as there is significant evidence of the broad-spectrum antimicrobial activity of nanomaterials and nanoparticles in particular. Moreover, owing to their considerable advantages regarding their efficient cargo dissolving, entrapment, encapsulation, or surface attachment, the possibility of forming antimicrobial groups for specific targeting and destruction, biocompatibility and biodegradability, low toxicity, and synergistic therapy, polymeric nanoparticles have received considerable attention as potential antimicrobial drug delivery agents. In this context, the aim of this paper is to provide an up-to-date overview of the most recent studies investigating polymeric nanoparticles designed for antimicrobial therapies, describing both their targeting strategies and their effects.

Development and Characterization of Biointeractive Gelatin Wound Dressing Based on Extract of Punica granatum Linn

Punica granatum Linn (pomegranate) extracts have been proposed for wound healing due to their antimicrobial, antioxidant, and anti-inflammatory properties. In this work, we designed biointeractive membranes that contain standard extracts of P. granatum for the purpose of wound healing. The used standard extract contained 32.24 mg/g of gallic acid and 41.67 mg/g of ellagic acid, and it showed high antioxidant activity (the concentration of the extract that produces 50% scavenging (IC50) 1.715 µg/mL). Compared to the gelatin-based membranes (GEL), membranes containing P. granatum extracts (GELPG) presented a higher maximal tension (p = 0.021) and swelling index (p = 0.033) and lower water vapor permeability (p = 0.003). However, no difference was observed in the elongation and elastic modulus of the two types of membranes (p > 0.05). Our wound-healing assay showed that a GELPG-treated group experienced a significant increase compared to that of the control group in their wound contraction rates on days 3 (p < 0.01), 7 (p < 0.001), and on day 14 (p < 0.001). The GELPG membranes promoted major histological changes in the dynamics of wound healing, such as improvements in the formation of granular tissue, better collagen deposition and arrangement, and earlier development of cutaneous appendages. Our results suggest that a biointeractive gelatin-based membrane containing P. granatum extracts has a promising potential application for dressings that are used to treat wounds.