Stabilized core/shell PVA/SA nanofibers as an efficient drug delivery system for dexpanthenol

Cancer Treatment Using Nanofibers: A Review

Currently, the number of patients with cancer is expanding consistently because of a low quality of life. For this reason, the therapies used to treat cancer have received a lot of consideration from specialists. Numerous anticancer medications have been utilized to treat patients with cancer. However, the immediate utilization of anticancer medicines leads to unpleasant side effects for patients and there are many restrictions to applying these treatments. A number of polymers like cellulose, chitosan, Polyvinyl Alcohol (PVA), Polyacrylonitrile (PAN), peptides and Poly (hydroxy alkanoate) have good properties for the treatment of cancer, but the nanofibers-based target and controlled drug delivery system produced by the co-axial electrospinning technique have extraordinary properties like favorable mechanical characteristics, an excellent release profile, a high surface area, and a high sponginess and are harmless, bio-renewable, biofriendly, highly degradable, and can be produced very conveniently on an industrial scale. Thus, nanofibers produced through coaxial electrospinning can be designed to target specific cancer cells or tissues. By modifying the composition and properties of the nanofibers, researchers can control the release kinetics of the therapeutic agent and enhance its accumulation at the tumor site while minimizing systemic toxicity. The core-shell structure of coaxial electrospun nanofibers allows for a controlled and sustained release of therapeutic agents over time. This controlled release profile can improve the efficacy of cancer treatment by maintaining therapeutic drug concentrations within the tumor microenvironment for an extended period.

Macroporous, Highly Hygroscopic, and Leakage-Free Composites for Efficient Atmospheric Water Harvesting

Hygroscopic composites based on hygroscopic salts and hydrogels are promising for atmospheric water harvesting (AWH), but their relatively low water production and possible salt leakage hinder real applications. Here, we report highly hygroscopic and leakage-free composites from loading LiCl into emulsion-templated sodium alginate and poly(vinyl alcohol) hydrogels with macroporous structures and interpenetrating polymer networks. The resulting composites exhibited an enhanced moisture uptake (up to 3.4 g g-1) and leakage-free behavior even at an extremely high relative humidity (RH) of 90%. Moreover, the composites showed accelerated adsorption, with high adsorption (0.803 g g-1 water at 25 °C and 90% RH within 1 h) and desorption due to the emulsion-templated, highly interconnected macropores. The hygroscopic composites obtained 1.12 g g-1 water per adsorption-desorption collection cycle and showed high reusability, without obvious deterioration in adsorption, desorption, and collection after 10 cycles. With the presence of carbon nanotubes, solar-driven AWH could be realized, without the requirement of additional energy. The highly hygroscopic and leakage-free composites with enhanced and accelerated adsorption and desorption are excellent candidates for efficient AWH.

Antibacterial Surgical Sutures Developed Using Electrostatic Yarn Wrapping Technology

A significant amount of research has been conducted on applying functional materials as surgical sutures. Therefore, research on how to solve the shortcomings of surgical sutures through available materials has been given increasing attention. In this study, hydroxypropyl cellulose (HPC)/PVP/zinc acetate nanofibers were coated on absorbable collagen sutures using an electrostatic yarn winding technique. The metal disk of an electrostatic yarn spinning machine gathers nanofibers between two needles with positive and negative charges. By adjusting the positive and negative voltage, the liquid in the spinneret is stretched into fibers. The selected materials are toxicity free and have high biocompatibility. Test results indicate that the nanofiber membrane comprises evenly formed nanofibers despite the presence of zinc acetate. In addition, zinc acetate can effectively kill 99.9% of E. coli and S. aureus. Cell assay results indicate that HPC/PVP/Zn nanofiber membranes are not toxic; moreover, they improve cell adhesion, suggesting that the absorbable collagen surgical suture is profoundly wrapped in a nanofiber membrane that exerts antibacterial efficacy and reduces inflammation, thus providing a suitable environment for cell growth. The employment of electrostatic yarn wrapping technology is proven effective in providing surgical sutures with antibacterial efficacy and a more flexible range of functions.

Nanoemulsion-Based Hydrogels and Organogels Containing Propolis and Dexpanthenol: Preparation, Characterization, and Comparative Evaluation of Stability, Antimicrobial, and Cytotoxic Properties

Recently, nanoemulsion-based gels have become very popular for dermal drug delivery, overcoming the disadvantages of conventional semi-solid drug forms. The aim of this study is to prepare and characterize nanoemulsion-based hydrogels and organogels containing combined propolis and dexpanthenol, and to compare their stability, antimicrobial, and cytotoxicity properties. Within the scope of characterization studies, organoleptic properties, drug content, morphology, pH, gel-sol conversion temperature, spreadability, viscosity, FT-IR, and release properties were evaluated in hydrogels and organogels. The characterization studies carried out were subjected to short-term stability evaluation at room temperature and refrigerator for 3 months. While no phase separation was observed in any of the formulations kept in the refrigerator, phase separation was observed in four formulations kept at room temperature. The release study successfully obtained an extended release for propolis and dexpanthenol. In the antimicrobial susceptibility study, Hydrogel 1 showed activity against S. aureus, while Organogel 1 showed activity against both S. aureus and S. epidermidis. In the cytotoxicity study against HDFa cells, both Hydrogel 1 and Organogel 1 were found to be nontoxic at low doses. These hydrogels and organogels, which contain propolis and dexpanthenol in combination for the first time, are promising systems that can be used in wound and burn models in the future.

Control of drug release from cotton fabric by nanofibrous mat

A drug delivery system (DDSs) was developed in the present study based on textile substrates as drug carriers and electrospun nanofibers as a controller of release rate. Three types of drugs consisting of ciprofloxacin (CIP), clotrimazole (CLO), and benzalkonium chloride (BEN) were loaded into the cover glass (CG) and cotton fabrics (CF1 and CF2) separately. Then, the drug-loaded substrates were coated with polycaprolactone (PCL) and polycaprolactone/gelatin (PCL/Gel) nanofibers with various thicknesses. The morphology and hydrophilicity of the electrospun nanofibers and the release profile of drug-loaded samples were investigated. FTIR, XRD, and in vitro biodegradability analysis were analyzed to characterize the drug delivery system. A morphological study of electrospun fibers showed the mean diameter of the PCL and PCL/Gel nanofibers 127 ± 25 and 178 ± 38 nm, respectively. The drug delivery assay revealed that various factors affect the rate of drug releases, such as the type of drug, the type of drug carrier, and the thickness of the covered nanofibers. The study highlights the ability of drugs to load substrates with coated nanofibers as controlled drug delivery systems. In conclusion, it is shown that the obtained samples are excellent candidates for future wound dressing applications.

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.

Antibacterial Multi-Layered Nanocellulose-Based Patches Loaded with Dexpanthenol for Wound Healing Applications

Antibacterial multi-layered patches composed of an oxidized bacterial cellulose (OBC) membrane loaded with dexpanthenol (DEX) and coated with several chitosan (CH) and alginate (ALG) layers were fabricated by spin-assisted layer-by-layer (LbL) assembly. Four patches with a distinct number of layers (5, 11, 17, and 21) were prepared. These nanostructured multi-layered patches reveal a thermal stability up to 200 °C, high mechanical performance (Young's modulus ≥ 4 GPa), and good moisture-uptake capacity (240-250%). Moreover, they inhibited the growth of the skin pathogen Staphylococcus aureus (3.2-log CFU mL-1 reduction) and were non-cytotoxic to human keratinocytes (HaCaT cells). The in vitro release profile of DEX was prolonged with the increasing number of layers, and the time-dependent data imply a diffusion/swelling-controlled drug release mechanism. In addition, the in vitro wound healing assay demonstrated a good cell migration capacity, headed to a complete gap closure after 24 h. These results certify the potential of these multi-layered polysaccharides-based patches toward their application in wound healing.

Crosslinked-polyvinyl alcohol-carboxymethyl cellulose/ZnO nanocomposite fibrous mats containing erythromycin (PVA-CMC/ZnO-EM): Fabrication, characterization and in-vitro release and anti-bacterial properties

Recently, nanocomposite nanofibers have been extensively used for biomedical applications. It is expected that simultaneous incorporation of antibiotic drugs and ZnO nanoparticles into nanofiber resulted in providing the synergistic anti-bacterial effect. The main aim of the present study is to fabricate polyvinyl alcohol (PVA)/carboxymethyl cellulose (CMC)-ZnO nanocomposite fibrous mats containing erythromycin (EM) drug and crosslink them using 2% glutaraldehyde vapor and 3% AlCl₃ alcoholic solution. The fabricated nanofibers characterized via TGA, FTIR, TEM, and SEM, indicating that the addition of ZnO nanoparticles and EM molecules into the fabricated nanofibers resulted in changing their average diameter. Their anti-bacterial activity was studied against S. aureus and E. coli and found that PVA-CMC/ZnO-EM nanofibers show excellent antimicrobial activity. In-vitro release profile showed that EM release from PVA-CMC/ZnO-EM nanofibers was slowly increased. Sustained drug release profile and excellent anti-bacterial activity of PVA-CMC/ZnO-EM nanofiber indicated that it was an ideal biomaterial for wound dressings.

Synthesis and evaluation of water soluble pH sensitive poly (vinyl alcohol)-doxorubicin conjugates

The accuracy of spatiotemporal control cargo delivery and release are primordial to enhance the therapeutic efficiency and decrease the undesirable effects, in this context a novel prodrug were developed based on biocompatible polyvinyl alcohol (PVA) substrate. PVA was conjugated to doxorubicin (PVA-DOX) via an acid-labile hydrazone linkage. PVA was first functionalized with acidic groups, then reacted with hydrazine hydrate to form an amide bond. The amine group of PVA hydrazide was linked to carbonyl group (C = O) of DOX to form a pH sensitive hydrazone bond. The molecular structure of the PVA-DOX was confirmed by FTIR, XPS, and ¹H-NMR analysis methods. The degree of grafting were evaluated by TGA and confirmed by XPS, which reveals the successful bond attachment of DOX to PVA. Our findings confirm pH dependent DOX release from PVA-DOX prodrug with faster release rate in acidic environment (pH 5.0, pH 6.0) and slower release rate in neutral pH environment (pH 7.4). Compared to the primary DOX, our synthesized PVA-DOX conjugates could exhibit a promising therapeutic effect, high biocompatibility and zero premature release. The results prove the successful synthesis of PVA-DOX conjugates with high efficiency.