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Recurrent aphthous stomatitis (RAS) is a common condition that manifests as ulcerative lesions in the oral mucosa. In this study, bilayer, mucoadhesive nanofibers loaded with pomegranate flower extract (PFE) were prepared using thiolated gelatin (TGel) and thiolated chitosan (TCS) as the active layer and drug-free polycaprolactone (PCL) as the backing layer. Gelatin (Gel) and chitosan (CS) were successfully thiolated (proven by Ellman's assay, solubility, 1 H NMR, FTIR, Raman spectroscopy, and XRD) and electrospun into active nanofibrous layers with a diameter of 356.9 nm. The in vitro release assay showed extended release of PFE, reaching about 57 % drug release in 48 h, fitted to the Korsmeyer-Peppas kinetics. FTIR, Raman spectroscopy, and XRD also showed the characteristic peaks of the nanofibers and their components. The nanofibers also exhibited significant hydrophilicity (contact angle of 47-49°), mucoadhesion (432.7 Pa), antioxidant capabilities (93.3 ± 0.2 %), and antibacterial effects against Staphylococcus aureus and Pseudomonas aeruginosa. Furthermore, PFE-loaded thiolated nanofibers significantly accelerated wound healing and epithelial tissue regeneration in vivo, reducing the ulcer area from 187 ± 19 mm on the 1st day to 68 ± 6 on the 7th day. Overall, bilayer PFE-loaded nanofibers based on TCS and TGel showed promising potential for treating RAS., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Ltd. All rights reserved.)

Objective: The objective of this study was to evaluate the effect of lipid structure on physicochemical properties of chitosan-fatty acid nanomicelles and prepare an optimum ciprofloxacin-loaded formulation from these conjugates which could enhance the antibacterial effects of drug against some important pathogens like P. aeruginosa., Significance: Nowadays, resistance in infectious diseases is a growing worldwide concern. Nanocarriers can increase the therapeutic index and consequently reduce the antibiotic resistance. By site-specific delivery of drug, the adverse effects of broad-spectrum antibiotics such as ciprofloxacin would be reduced., Methods: Fatty acid grafted chitosan conjugates were synthetized in the presence of 1-ethyl-3-(3-dimethylaminopropyl) carbodiimide. The effects of fatty acid type (stearic acid, palmitic acid, and linoleic acid) on physicochemical properties of conjugates were investigated. Ciprofloxacin was encapsulated in nanomicelles by thin film hydration method. Also, the preparation process was optimized with a central composite design. The antibacterial effect of optimum formulation against P. aeruginosa, K. pneumoniae, and S. pneumoniae species was determined., Results: All conjugates were synthetized with high yield values and the substitution degrees ranged between 2.13 and 35.46%. Ciprofloxacin was successfully encapsulated in nanomicelles. The optimum formulation showed high drug loading (≈ 19%), with particle size of about 260 nm and a sustained release profile of ciprofloxacin. The minimum inhibitory concentrations of ciprofloxacin in optimum formulation against P. aeruginosa and K. pneumoniae species were 4 and 2 times lower in comparison with the free drug, respectively., Conclusions: The antibacterial effect of ciprofloxacin was improved by encapsulation of drug in chitosan nanomicelles.

The purpose of this study was to prepare and characterize a hybrid system of moxifloxacin loaded niosomes incorporated into chitosan gel as a potential carrier for topical antimicrobial delivery. The prepared system was characterized regarding entrapment efficiency, particle size, zeta potential, in vitro drug release kinetics, morphology, FTIR analysis, bioadhesive strength and rheological behavior. The effect of different formulation parameters (surfactant type, surfactant to drug ratio, cholesterol percentage and loading methodology) on moxifloxacin entrapment and drug release was evaluated. The antibacterial effectiveness of various formulations was also assessed by measuring the minimal inhibitory concentrations, minimal bactericidal concentrations and agar diffusion assay using Pseudomonas aeruginosa and Staphylococcus aureus as model pathogens. The optimized niosomal formulation showed 73% drug entrapment, 47% drug release in 8h and was ∼290 nm in particle diameter and negatively charged (ζ∼-23 mV). The gel-embedded niosomes exhibited pseudo-plastic flow behavior and more sustained drug release profile compared to niosomes. The niosomal formulation of moxifloxacin was the most efficient system against P. aeruginosa, while gel based formulations were superior against S. aureus. Taken together, moxifloxacin-in-niosomes-in-gels hold great promise for topical microbial infections., (Copyright © 2016 Elsevier B.V. All rights reserved.)

Since 1980 after introducing the concept of live cell encapsulation by Lim et al., this technology has received enormous attention. Several studies have been conducted to improve this technique; different polymers, either natural or synthetic, have been used as microcapsules' making materials and different substances as coating layers. Literature review leads us to the conclusion that alginate (Alg) multilayer microcapsules and, in particular, alginate-poly l-lysine (PLL)-alginate (APA) are the most used structures for live cell encapsulation. Although, disadvantages of PLL (e.g., weak mechanical strength and low biocompatibility) made researchers work on other cationic polymers to find an alternative. This review aims to discuss more popularly suggested cationic polymers such as poly l-ornithine (PLO), chitosan, etc. As alternatives for PLL and, more importantly, we want to take a closer look to see which one of these systems are closer to clinical applications. [ABSTRACT FROM AUTHOR]

Many herbs and spices have been recommended traditionally as galactagogues and several commercial formulations prepared using herbs. Due to the presence of various compounds such as polyphenols, flavonoids, isoflavones, and terpenes, bitter and stringent taste is elicited that make the consumption of these herbal preparations unpleasant. Moreover, these compounds are unstable when exposed to environmental conditions. In this regard, different approaches are used for taste masking such as microencapsulation. In the present study, microcapsules containing herbal galactagogue extract were developed through emulsification/ external gelation and Box-Behnken design was used to investigate the effects of independent variables (sodium alginate: 1-1.5%, calcium chloride: 0.2-1% and extract concentrations: 1-5%) on encapsulation efficiency (EE%). Following evaluation of the model, the optimum condition of encapsulation process was selected as 1.49% sodium alginate, 0.84 CaCl2, and 1.58% extract with EE% of 77.97%. Microcapsules had an acceptable spherical morphology and the results of Fourier transform-infrared spectroscopy (FTIR) revealed the presence of the extract within the microcapsules. The mean diameters of the uncoated and chitosan-coated microcapsules were 52 and 123 µm and encapsulation yield was 50.21 and 69.7%, respectively. The polydispersity index of 0.45 and 0.48 were an indicative of polydisperse nature of the microcapsules. The loss of flavonoids in microcapsules stored at two different temperatures was insignificant. The in-vitro release in simulated gastric fluid (SGF; pH 1.2) and simulated intestinal fluid (SIF; pH 7.4) were 48.1% and 80.11%, respectively during 24 h. The prepared extract-loaded microcapsules have potential to be used in matrices with neutral pH. [ABSTRACT FROM AUTHOR]

Chitosan-carboxymethyl cellulose (CMC) full polysaccharide membrane was prepared by cross-linking of chitosan with CMC dialdehyde and subsequent reductive amination. CMC dialdehyde molecule was prepared by periodate oxidation of CMC and then applied as a cross-linking agent to form a new membrane network. The properties of oxidized CMC were investigated by various methods such as Fourier transform infrared (FT-IR) spectroscopy, 1H NMR spectroscopy, and viscosity test. Then, novel chitosan-CMC silver nanocomposite was prepared using chitosan-CMC as a carrier. The structure of the chitosan-CMC membrane and the silver nanocomposite were confirmed by FT-IR spectroscopy, scanning electron microscopy (SEM), transmission electron microscopy (TEM), and thermogravimetric analysis (TGA). TEM images indicate that the chitosan-CMC nanocomposite comprises silver nanoparticles with diameters in the range of about 5-20 nm. The antibacterial studies of the nanocomposite were also evaluated. The chitosan-CMC silver nanocomposite demonstrates good antibacterial activity against Staphylococcus aureus, Pseudomonas aeruginosa, and Escherichia coli. Copyright © 2016 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Prolonged and impaired wound healing is a serious complication, and there is an emerging demand for strategies to overcome this problem. In this study, we developed electrospun bilayer nanofibers consisting of a chitosan/PVA active layer loaded with pomegranate flower extract (PFE) and a PCL inactive back layer. Structural, morphological, and physicochemical properties of nanofibers were characterized and wound healing effects of PFE-loaded nanofibers were assessed by in vitro and in vivo experiments, including antibacterial tests, wound closure measurements, and histological and immunohistochemical (IHC) analyses. Nanofibers with optimum formulation showed good hydrophilicity, a mean diameter of 404 nm, and an average roughness of 217 nm. TGA and FTIR studies exhibited typical absorption characteristics of PFE, PCL, and PVA and the compatibility of PFE with the components of bilayer nanofibers. The cumulative amount of PFE released from the monolayer and bilayer fibers after 6 h was measured to be 100% and 64%, respectively, indicating the more sustained release of PFE from bilayer scaffolds. Based on mechanical studies, a more ductile behavior was observed for bilayer fibers than monolayer fibers. The antibacterial assay for PFE-loaded nanofibers exhibited an inhibition zone with a diameter of 19.0 ± 0.5 mm and 15.8 ± 0.3 mm for S. aureus and P. aeruginosa , respectively. PFE-loaded nanofiber exposure contributed to faster wound closure (88% in 14 days) and a significant rise in the expression of α-SMA, CD31, collagen I, and vimentin, indicating a higher tissue regeneration rate for PFE - loaded nanofibers over other treatment groups. In conclusion, bilayer nanofibers containing PFE have a promising potential for wound healing acceleration. [Display omitted] • Pomegranate flower extract-loaded chitosan/PVA/PCL nanofibers were fabricated. • Bilayer nanofibers proposed a ductile behavior and a sustained drug release. • Nanofibers showed antibacterial effects against S. aureus and P. aeruginosa. • In vivo exposure led to improved wound closure and increased tissue regeneration. • Pomegranate flower extract-loaded nanofibers can accelerate wound healing process. [ABSTRACT FROM AUTHOR]