Electrospun Polymer Materials with Fungicidal Activity: A Review.

In recent years, there has been special interest in innovative technologies such as polymer melt or solution electrospinning, electrospraying, centrifugal electrospinning, coaxial electrospinning, and others. Applying these electrokinetic methods, micro- or nanofibrous materials with high specific surface area, high porosity, and various designs for diverse applications could be created. By using these techniques it is possible to obtain fibrous materials from both synthetic and natural biocompatible and biodegradable polymers, harmless to the environment. Incorporation of low-molecular substances with biological activity (e.g., antimicrobial, antifungal) is easily feasible. Moreover, biocontrol agents, able to suppress the development and growth of plant pathogens, have been embedded in the fibrous materials as well. The application of such nanotechnologies for the creation of plant protection products is an extremely promising new direction. This review emphasizes the recent progress in the development of electrospun fungicidal dressings and their potential to be applied in modern agriculture.

Еlectrospun сellulose acetate membranes decorated with curcumin-PVP particles: preparation, antibacterial and antitumor activities.

Curcumin (Curc) exhibits anti-inflammatory, antibacterial and antitumor activity. However, its clinical application is limited by its poor bioavailability related to its extremely low water solubility. Novel materials allowing enhanced release of Curc in aqueous medium were obtained. The new materials consisted of electrospun fibers from cellulose acetate (CA) (mean fiber diameter ca. 780 nm ± 110 nm) with electrosprayed Curc/polyvinylpyrrolidone (Curc/PVP) particles. Scanning electron microscopy (SEM) showed that separated and evenly distributed particles of Curc/PVP were deposited on the surface of the mats and on the inner layers of the mat. X-ray diffraction studies showed that Curc was in amorphous state. In vitro studies demonstrated that Curc release was facilitated from Curc/PVP-on-CA mats (ca. 78% for 24 h) compared with the materials in which Curc was incorporated in CA fibers (17% for 24 h). Moreover, the curcumin-containing materials exhibited antibacterial activity against Gram-positive bacteria Staphylococcus aureus (S. aureus) and Gram-negative bacteria Escherichia coli (E. coli). Curc/PVP-on-CA fibrous mats exhibited high in vitro cytotoxicity towards HeLa tumor cells. Therefore, the obtained materials are promising for antibacterial wound dressing applications as well as for application in local treatment of cervical tumors.

From design of bio-based biocomposite electrospun scaffolds to osteogenic differentiation of human mesenchymal stromal cells.

Electrospinning coupled with electrospraying provides a straightforward and robust route toward promising electrospun biocomposite scaffolds for bone tissue engineering. In this comparative investigation, four types of poly(3-hydroxybutyrate) (PHB)-based nanofibrous scaffolds were produced by electrospinning a PHB solution, a PHB/gelatin (GEL) mixture or a PHB/GEL/nHAs (hydroxyapatite nanoparticles) mixed solution, and by electrospinning a PHB/GEL solution and electrospraying a nHA dispersion simultaneously. SEM and TEM analyses demonstrated that the electrospun nHA-blended framework contained a majority of nHAs trapped within the constitutive fibers, whereas the electrospinning-electrospraying combination afforded fibers with a rough surface largely covered by the bioceramic. Structural and morphological characterizations were completed by FTIR, mercury intrusion porosimetry, and contact angle measurements. Furthermore, an in vitro investigation of human mesenchymal stromal cell (hMSC) adhesion and proliferation properties showed a faster cell development on gelatin-containing scaffolds. More interestingly, a long-term investigation of hMSC osteoblastic differentiation over 21 days indicate that hMSCs seeded onto the nHA-sprayed scaffold developed a significantly higher level of alkaline phosphatase activity, as well as a higher matrix biomineralization rate through the staining of the generated calcium deposits: the fiber surface deposition of nHAs by electrospraying enabled their direct exposure to hMSCs for an efficient transmission of the bioceramic osteoinductive and osteoconductive properties, producing a suitable biocomposite scaffold for bone tissue regeneration.

Chitosan/Hyaluronate Complex-Coated Electrospun Poly(3-hydroxybutyrate) Materials Containing Extracts from Melissa officinalis and/or Hypericum perforatum with Various Biological Activities: Antioxidant, Antibacterial and In Vitro Anticancer Effects.

The present study aimed to fabricate innovative fibrous materials with various biological activities from poly(3-hydroxybutyrate), sodium hyaluronate (HA), chitosan (Ch), Melissa officinalis (MO), Hypericum perforatum (HP) extract, or a combination of both extracts. Electrospinning or electrospinning followed by dip coating and the subsequent formation of a polyelectrolyte complex were the methods used to prepare these materials. Scanning electron microscopy (SEM), transmission electron microscopy (TEM), thermogravimetric analysis (TGA), and attenuated total reflection-Fourier transform infrared spectroscopy (ATR-FTIR) were applied for investigating the morphology of materials, their thermal characteristics, and their surface chemical composition. The composition and design of the mats had an influence on the in vitro release behavior of the main bioactive compounds present in the MO and HP extracts incorporated in the materials. It was found that as-created materials comprising a combination of both extracts and a Ch/HA complex exerted higher antioxidant activity than that of (non-)coated MO-containing mats and Ch/HA-coated mats containing HP. The novel materials manifested antibacterial efficacy towards the pathogenic bacteria S. aureus and E. coli, as evidenced by the performed microbiological screening. Furthermore, the mats possessed a great growth inhibitory effect on HeLa cancer cells but had a less pronounced effect on the growth of normal mouse BALB/3T3 fibroblasts. The loading of both extracts in the mats and the formation of coating led to the enhancement of the in vitro anticancer and antibacterial activities of the materials. Thus, the novel materials have potential for use in local cancer therapy as well as for use as wound dressings.

5-Amino-8-hydroxyquinoline-containing Electrospun Materials Based on Poly(vinyl alcohol) and Carboxymethyl Cellulose and Their Cu2+ and Fe3+ Complexes with Diverse Biological Properties: Antibacterial, Antifungal and Anticancer.

Novel fibrous materials with diverse biological properties containing a model drug of the 8-hydroxyquinoline group-5-amino-8-hydroxyquinoline (5A8Q)-were fabricated using a one-pot method by electrospinning poly(vinyl alcohol) (PVA)/carboxymethyl cellulose (CMC)/5A8Q solutions. Experiments were performed to prepare Cu2+ (Fe3+) complexes of the crosslinked PVA/CMC/5A8Q materials. The formation of complexes was proven by using scanning electron microscopy (SEM), attenuated total reflection Fourier-transform infrared (ATR-FTIR) spectroscopy, energy-dispersive X-ray spectroscopy (EDX) and X-ray photoelectron spectroscopy (XPS). The release of 5A8Q and 5A8Q.Cu2+ (Fe3+) was studied and their in vitro release profiles were mostly impacted by the hydrophilic/hydrophobic properties of the materials. The performed microbiological assays revealed that fibrous materials containing 5A8Q and their complexes exhibited good antibacterial and antifungal efficacy. Their activity was stronger against bacteria S. aureus than against bacteria E. coli and fungi C. albicans. Cell viability tests using MTT showed that the presence of 5A8Q and its complexes in the fibrous materials resulted in a significant decrease in the HeLa and MCF-7 cancer cell viability for the various times of cell incubation. Moreover, the observed cytotoxicity of the mats against cancer cells was greater than that against non-cancer HaCaT keratinocytes. All these properties make the novel materials potential candidates for the design of wound healing materials and as drug delivery systems for local therapy of cervical and breast cancer.

Electrospun Fibers of Biocompatible and Biodegradable Polyesters, Poly(Ethylene Oxide) and Beeswax with Anti-Bacterial and Anti-Fungal Activities.

Fibrous materials composed of core-sheath fibers from poly(ethylene oxide) (PEO), beeswax (BW) and 5-nitro-8-hydroxyquinoline (NQ) were prepared via the self-organization of PEO and BW during the single-spinneret electrospinning of a homogeneous blend solution of the partners. Additionally, the application of the same approach enabled the preparation of fibrous materials composed of core-double sheath fibers from PEO, poly(L-lactide) (PLA) and NQ or 5-chloro-7-iodo-8-hydroxyquinoline (CQ), as well as from PEO, poly(ε-caprolactone) (PCL) and NQ. The consecutive selective extraction of BW and of the polyester with hexane and tetrahydrofuran, respectively, evidenced that core-double sheath fibers from PEO/polyester/BW/drug consisted of a PEO core, a polyester inner sheath and a BW outer sheath. In order to evaluate the possibility of the application of fibrous materials from PEO/BW/NQ, PEO/PLA/BW/NQ, PEO/PCL/BW/NQ and PEO/PLA/BW/CQ for plant protection, microbiological studies were performed using both phytopathogenic microorganisms (Pseudomonas corrugata, Fusarium graminearum and Fusarium avenaceum) and beneficial microorganisms (Pseudomonas chlororaphis, Bacillus amyloliquefaciens and Trichoderma asperellum). It was found that the fibrous materials had anti-bacterial and anti-fungal activity against both phytopathogenic and beneficial microorganisms. This is the first report on the activity of fibrous materials loaded with 8-hydroxyquinoline derivatives not only against phytopathogenic but also against beneficial microorganisms that are of importance in agriculture.

Physico-Chemical, Mechanical, and Biological Properties of Polylactide/Portulaca oleracea Extract Electrospun Fibers.

Electrospinning was used to create fibrous polylactide (PLA) materials loaded with Portulaca oleracea (P. oleracea) plant extract obtained by supercritical carbon dioxide. Morphological, physico-chemical, mechanical, and biological characteristics of the fibers were studied. According to the SEM results, the diameters of smooth and defect-free fibers fabricated by a one-pot electrospinning method were at micron scale. All the obtained materials possess good mechanical properties. Additionally, it was found that the composite fibers exhibited considerable antioxidant activity. The antimicrobial activity of the fibrous materials against Gram-positive and Gram-negative bacteria was determined as well. In vitro studies showed that the electrospun biomaterials had no cytotoxic effects and that the combination of PLA and the P. oleracea extract in the fiber structure promoted cell survival and proliferation of normal mouse fibroblasts. The obtained results reveal that microfibrous mats containing the polyester-PLA and the plant extract-P. oleracea can be suitable for applications in wound healing.

Electrospun PLA-Based Biomaterials Loaded with Melissa officinalis Extract with Strong Antioxidant Activity.

In the present study, the plant extract Melissa officinalis (M. officinalis) was successfully loaded in polymer fibrous materials on the basis of a biodegradable polyester-poly(L-lactide) (PLA) and biocompatible polyether-polyethylene glycol (PEG) by applying the electrospinning method. The optimal process conditions for the preparation of hybrid fibrous materials were found. The extract concentration was varied-0, 5 or 10 wt% in respect of the polymer weight, in order to study its influence on the morphology and the physico-chemical properties of the obtained electrospun materials. All the prepared fibrous mats were composed of defect-free fibers. The mean fiber diameters of the PLA, PLA/M. officinalis (5 wt%) and PLA/M. officinalis (10 wt%) were 1370 ± 220 nm, 1398 ± 233 nm and 1506 ± 242 nm, respectively. The incorporation of the M. officinalis into the fibers resulted in slight increase of the fiber diameters and in increase of the water contact angle values to 133°. The presence of the polyether in the fabricated fibrous material assisted the wetting of the materials imparting them with hydrophilicity (the value of the water contact angle become 0°). Extract-containing fibrous materials displayed strong antioxidant activity as determined by the 2,2-diphenyl-1-picryl-hydrazyl-hydrate free radical method. The DPPH solution color changed to yellow and the absorbance of the DPPH radical dropped by 88.7% and 91% after being in contact with PLA/M. officinalis and PLA/PEG/M. officinalis mats, respectively. These features revealed the M. officinalis-containing fibrous biomaterials promising candidates for pharmaceutical, cosmetic and biomedical use.

Innovative Fibrous Materials Loaded with 5-Nitro-8-hydroxyquinoline via Electrospinning/Electrospraying Demonstrate Antioxidant, Antimicrobial and Anticancer Activities.

A new type of fibrous mat based on a cellulose derivative-cellulose acetate (CA) or CA and water-soluble polymers (polyvinylpyrrolidone, PVP or poly(vinyl alcohol), PVA)-loaded with the model drug 5-nitro-8-hydroxyquinoline (5N) was fabricated via electrospinning or electrospinning in conjunction with electrospraying. Scanning electron microscopy (SEM), X-ray diffraction analysis (XRD), Fourier-transform infrared spectroscopy (FTIR), water contact angle measurements and ultraviolet-visible spectroscopy (UV-Vis) were used for the complex characterization of the obtained novel material. The decoration of CA fibers with a water-soluble polymer containing the drug resulted in the facilitation of wetting and fast drug release. The 5N-containing fibrous material showed antioxidant activity. Moreover, the proposed materials' antibacterial and antifungal properties were tested against S. aureus, E. coli, P. aeruginosa and C. albicans. Well-distinguished, sterile zones with diameters above 3.5 cm were observed around all 5N-containing mats. The mats' cytotoxicity toward HeLa carcinoma cells and normal mouse BALB/c 3T3 fibroblasts was assessed. The 5N-in-CA, PVP,5N-on-(5N-in-CA) and PVA,5N-on-(5N-in-CA) fibrous mats possessed anticancer efficacies and much lower levels of toxicity against normal cells. Therefore, the as-created novel electrospun materials, which are based on polymers loaded with the drug 5N via electrospinning/electrospraying, can potentially be applied for topical wound healing and for local cancer therapy.

Eco-Friendly Hybrid PLLA/Chitosan/Trichoderma asperellum Nanomaterials as Biocontrol Dressings against Esca Disease in Grapevines.

Fungi constitute the largest number of plant pathogens and are responsible for a range of serious plant diseases. Phaeomoniella chlamydospora (P. chlamydospora) and Phaeoacremonium aleophilum (P. aleophilum) are the main fungal pathogens causing esca disease in grapevines. On the other hand, there are beneficial microorganisms such as Trichoderma spp., which are able to control the growth of many phytopathogens. In the present study, innovative, eco-friendly hybrid nanomaterials were created by electrospinning PLLA, followed by the formation of a film of chitosan/Trichoderma asperellum (T. asperellum) spores on the fibers. The polymer carrier used in this study plays an active role in ensuring the viability of the biological agent during storage and, when placed in contact with moisture, ensures the agent's normal development. Oligochitosan, as well as low molecular weight and high molecular weight chitosan, were used. The effects of chitosan molecular weight on the dynamic viscosity of chitosan solutions, film formation, mechanical properties, spore incorporation and growth were studied. The morphology of the prepared nanomaterials, and the presence of a film based on the formation of chitosan/T. asperellum spores on the PLLA fibers, were examined using scanning electron microscopy (SEM). The surface chemical compositions of the fibrous materials were studied using attenuated total reflection Fourier transform infrared spectroscopy (ATR-FTIR). The mechanical properties of the obtained materials were also tested. The microbiological screening that was performed revealed that the eco-friendly hybrid nanomaterials incorporated with the beneficial microorganism, T. asperellum, to hamper the growth of the pathogenic P. chlamydospora and P. aleophilum fungi. The suppression rate depended on the viscosity of the chitosan solution used for the film formation. The use of oligochitosan resulted in the most effective infection of the material with T. asperellum spores. The environmentally friendly hybrid nanomaterials obtained in this study-in which the bioagent was embedded-are promising bioactive dressings for protecting grapevines against esca disease.

Core/Double-Sheath Composite Fibers from Poly(ethylene oxide), Poly(L-lactide) and Beeswax by Single-Spinneret Electrospinning.

The conventional approach for preparation of core-sheath fibers is coaxial electrospinning. Single-spinneret electrospinning of emulsions is a much less common method to obtain core-sheath fibers. Core-sheath structure may be generated by electrospinning of homogeneous blend solutions; however, reports on such cases are still scarce. Herein, the preparation of nanofibrous composites from poly(ethylene oxide) (PEO), poly(L-lactide) (PLA) and beeswax (BW) by single-spinneret electrospinning of their homogeneous blend solutions in chloroform is reported. The produced fibers had core/double-sheath structure with a PEO core, PLA inner sheath and BW outer sheath. This original fiber structure was evidenced by transmission electron microscopy, selective extraction of BW or PEO, and X-ray photoelectron spectroscopy. The PLA/BW double sheath led to hydrophobicity of the PEO/PLA/BW mats. The tensile tests revealed that PEO/PLA/BW mats had substantially improved mechanical behavior as compared to PEO, PLA and PEO/BW mats. PEO/PLA/BW mats can be used as drug carriers as evidenced by the one-pot incorporation of the model drug 5-nitro-8-hydroxyquinoline (NQ) into the fibrous materials. Microbiological tests showed that PEO/PLA/BW/NQ had antimicrobial activity. Therefore, the new materials are promising for wound healing applications.

Quercetin- and Rutin-Containing Electrospun Cellulose Acetate and Polyethylene Glycol Fibers with Antioxidant and Anticancer Properties.

Innovative fibrous materials from cellulose derivative, cellulose acetate (CA) and water-soluble polyether, polyethylene glycol (PEG) loaded with natural biologically active compounds (BAC), quercetin (QUE) and rutin (RUT), have been successfully fabricated by blend electrospinning and dual electrospinning. Scanning electron microscopy revealed that the mean fiber diameters of all the obtained fibers were in the nanometer range. QUE and RUT incorporated in the fibrous mats were in the amorphous state, as evidenced by the performed differential scanning calorimetry (DSC) and X-ray diffraction (XRD) analysis. The presence of the polyether in the developed fibrous material assisted the in vitro release of the biologically active compounds by improving the hydrophilicity and wettability of the mats. Rutin-containing fibrous materials manifest the highest antioxidative activity, as determined by the 2,2-diphenyl-1-picryl-hydrazyl-hydrate free radical method. The cytotoxicity of the fabricated novel materials was evaluated using a tumor cell line and normal mouse fibroblast cells. The mats containing QUE and QUE/RUT independent of the applied spinning method show a higher cytotoxic effect against cancer cells and 3 to 4.5 times lower cytotoxicity to a noncancer cell line. These features make the quercetin- and rutin-containing fibrous materials promising candidates for pharmaceutical, cosmetic, and biomedical use.

Core-Sheath-Like Poly(Ethylene Oxide)/Beeswax Composite Fibers Prepared by Single-Spinneret Electrospinning. Antibacterial, Antifungal, and Antitumor Activities.

Composite fibrous materials are prepared from poly(ethylene oxide) (PEO) and beeswax (BW) by single-spinneret electrospinning using chloroform as a common solvent. The obtained fibers have core-sheath-like structure, as evidenced by the water contact angle values and corroborated by the results on the elemental composition of the fiber's surface determined by X-ray photoelectron spectroscopy (XPS) and by analyses with scanning electron microscopy of fibers before and after selective extraction of PEO or BW. Furthermore, the core-sheath-like structure is proven by transmission electron microscopy. This is attributed to self-assembly of BW molecules on the surface of the formed fibers driven by the incompatibility between PEO and BW. 5-Nitro-8-hydroxyquinoline (NQ) is embedded as a model drug with antibacterial, antifungal, and anticancer properties in the PEO/BW fibrous materials. XPS analyses reveal that NQ is present on the surface of the PEO/BW/NQ materials. Using a purposely designed cell for fixation of the fibrous materials the NQ release in phosphate buffer solution with рН 7.4 is followed. The new PEO/BW/NQ fibrous materials exhibit antibacterial activity against S. aureus and E. coli, antifungal effect against C. albicans, and selective anticancer activity against HeLa (human cervical adenocarcinoma cells) and SH-4 (human melanoma cells) cell lines.

Electrospun 5-Chloro-7-iodo-8-hydroxyquinoline (Clioquinol)-Containing Poly(3-hydroxybutyrate)/Polyvinylpyrrolidone Antifungal Materials Prospective as Active Dressings against Esca.

Esca is a grapevine disease known for centuries which pertains to the group of so-called vine trunk diseases. Phaeomoniella chlamydospora (P. chlamydospora) and Phaeoacremonium aleophilum (P. aleophilum) are the two main fungal pathogens associated with esca. Novel fibrous materials with antifungal properties based on poly(3-hydroxybutyrate) (PHB), polyvinylpyrrolidone (PVP) and 5-chloro-7-iodo-8-hydroxyquinoline (clioquinol, CQ) were developed. One-pot electrospinning ("in" strategy) or electrospinning in conjunction with electrospraying ("on" strategy) were applied to obtain the materials. The materials' morphology and their surface chemical composition were examined using scanning electron microscopy (SEM), X-ray photoelectron spectroscopy (XPS) and attenuated total reflection Fourier transform infrared spectroscopy (ATR-FTIR). CQ incorporated in the bulk of the fibers or in PVP particles deposited on the fibers was in the amorphous phase, which was confirmed by differential scanning calorimetry (DSC) and X-ray diffraction analysis (XRD). The in vitro release of CQ depended on the composition of the electrospun materials and on their design. The performed microbiological screening revealed that, unlike the non-loaded mats, the fibrous mats loaded with CQ were effective in inhibiting the growth of the pathogenic P. chlamydospora and P. aleophilum fungi. Therefore, the created materials are promising as active dressings for grapevine protection against esca.

Bio-Based Electrospun Fibers from Chitosan Schiff Base and Polylactide and Their Cu2+ and Fe3+ Complexes: Preparation and Antibacterial and Anticancer Activities.

The Schiff base derivative (Ch-8Q) of chitosan (Ch) and 8-hydroxyquinoline-2-carboxaldehyde (8QCHO) was prepared and fibrous mats were obtained by the electrospinning of Ch-8Q/polylactide (PLA) blend solutions in trifluoroacetic acid (TFA). Complexes of the mats were prepared by immersing them in a solution of CuCl2 or FeCl3. Electron paramagnetic resonance (EPR) analysis was performed to examine the complexation of Cu2+(Fe3+) in the Ch-8Q/PLA mats complexes. The morphology of the novel materials and their surface chemical composition were studied by scanning electron microscopy (SEM), attenuated total reflection Fourier transform infrared spectroscopy (ATR-FTIR) and X-ray photoelectron spectroscopy (XPS). The performed microbiological screening demonstrated that in contrast to the neat PLA mats, the Ch-8Q-containing mats and their complexes were able to kill all S. aureus bacteria within 3 h of contact. These fibrous materials had efficiency in suppressing the adhesion of pathogenic bacteria S. aureus. In addition, Ch-8Q/PLA mats and their complexes exerted good anticancer efficacy in vitro against human cervical HeLa cells and human breast MCF-7 cells. The Ch-8Q-containing fibrous materials had no cytotoxicity against non-cancer BALB/c 3T3 mouse fibroblast cells. These properties render the prepared materials promising as wound dressings as well as for application in local cancer treatment.

Pegylated Curcumin Derivative: Water-Soluble Conjugates with Antitumor and Antibacterial Activity.

During the past years, the synthesis of polymer prodrug structures, based on natural phytochemical compounds with a great range of valuable biological properties, has become a promising solution in cancer prevention, imaging, and detection. Curcumin (Curc) remains one of the most studied natural products, due to the impressive palette of biological properties and the possibility to be easily loaded in various micro- and nanostructures and chemically modified. In this study, pegylated curcumin derivatives were prepared by a direct esterification reaction between poly(ethylene glycol)diacid (PEG of 600 g/mol molar mass, PEG600) and Curc in the presence of N,N'-dicyclohexylcarbodiimide (PEG600-Curc). The successful reaction resulted in a water-soluble stable product that was characterized by infrared spectroscopy (Fourier transform infrared (FT-IR)) and proton (1H) and carbon (13C) NMR. The effect of the pH values of buffer solutions on PEG600-Curc spectral properties (absorption and photoluminescence) was investigated by UV-vis and fluorescence spectrophotometry. Based on the biological tests, it was confirmed that PEG600-Curc exhibits cytotoxic activity against Graffi cell lines, as a function of the Curc concentration in the conjugate and the incubation time. PEG600-Curc antibacterial activity was validated in microbiological tests against pathogenic microorganisms such as Staphylococcus aureus. Most importantly, despite the covalent attachment of Curc to PEG and the slight reduction in the therapeutic index of the conjugate, both the anticancer and antimicrobial activities remain the highest reported, thus opening the gate for further, more clinically oriented studies.

Electrospun Poly(methyl methacrylate)/TiO2 Composites for Photocatalytic Water Treatment.

Electrospinning was successfully used for the one-step fabrication of poly(methyl methacrylate) (PMMA) fibers loaded with an inorganic photocatalyst-titanium oxide (TiO2). By tuning the PMMA/TiO2 ratio and the electrospinning conditions (applied voltage, needle tip-to-collector distance, and flow rates), PMMA/TiO2 composites with selected organic/inorganic ratios, tailored designs, and targeted properties were obtained. The morphology of the electrospun composites was affected by the amount of TiO2 incorporated into the PMMA fibers. In addition, the inorganic photocatalyst had an impact on the wettability, thermal stability, and optical properties of the electrospun composites. In particular, the surface wettability of the composites was strongly influenced by UV light irradiation and from hydrophobic became superhydrophilic. Moreover, PMMA/TiO2 composites had enhanced tensile strength in comparison with those of bare PMMA mats. The electrospun PMMA/TiO2 composites showed excellent photocatalytic efficiency against the model organic pollutant-methylene blue-which is very promising for the future development of membranes that are highly efficacious for photocatalytic water treatment.

Electrospun Polymer-Fungicide Nanocomposites for Grapevine Protection.

Nowadays, diseases in plants are a worldwide problem. Fungi represent the largest number of plant pathogens and are responsible for a range of serious plant diseases. Esca is a grapevine disease caused mainly by fungal pathogens Phaeomoniella chlamydospora (P. chlamydospora) and Phaeoacremonium aleophilum (P. aleophilum). The currently proposed methods to fight esca are not curative. In this study, polymer composites based on biodegradable polymer containing chemical fungicides with antifungal activity were successfully prepared by electrospinning. The obtained materials were hydrophobic with good mechanical properties. In vitro studies demonstrated that the fungicide release was higher from PLLA/K5N8Q fibrous mats (ca. 72% for 50 h) compared to the released drug amount from PLLA/5-Cl8Q materials (ca. 52% for 50 h), which is due to the better water-solubility of the salt. The antifungal activity of the fibrous materials against P. chlamydospora and P. aleophilum was studied as well. The incorporation of the fungicide in the biodegradable fibers resulted in the inhibition of fungal growth. The obtained materials are perspective candidates for the protection of vines from the penetration and growth of fungal pathogens.

Cellulose Acetate-Based Electrospun Materials with a Variety of Biological Potentials: Antibacterial, Antifungal and Anticancer.

Novel eco-friendly fibrous materials with complex activities from cellulose acetate and cellulose acetate/polyethylene glycol (CA,PEG) containing 5-chloro-8-hydroxyquinoline as a model drug were obtained by electrospinning. Several methods, including scanning electron microscopy, X-ray diffraction analysis, ultraviolet-visible spectroscopy, water contact angle measurements, and mechanical tests, were utilized to characterize the obtained materials. The incorporation of PEG into the fibers facilitated the drug release. The amounts of the released drug from CA/5-Cl8Q and CA,PEG/5-Cl8Q were 78 ± 3.38% and 86 ± 3.02%, respectively (for 175 min). The antibacterial and antifungal activities of the obtained materials were studied. The measured zones of inhibition of CA/5-Cl8Q and CA,PEG/5-Cl8Q mats were 4.0 ± 0.18 and 4.5 ± 0.2 cm against S. aureus and around 4.0 ± 0.15 and 4.1 ± 0.22 cm against E. coli, respectively. The complete inhibition of the C. albicans growth was detected. The cytotoxicity of the obtained mats was tested toward HeLa cancer cells, SH-4 melanoma skin cells, and mouse BALB/c 3T3 fibroblasts as well. The CA/5-Cl8Q and CA,PEG/5-Cl8Q materials exhibited anticancer activity and low normal cell toxicity. Thus, the obtained fibrous materials can be suitable candidates for wound dressing applications and for application in local cancer treatment.

8-Hydroxyquinoline-5-Sulfonic Acid-Containing Poly(Vinyl Alcohol)/Chitosan Electrospun Materials and Their Cu2+ and Fe3+ Complexes: Preparation, Antibacterial, Antifungal and Antitumor Activities.

Novel poly(vinyl alcohol) (PVA)/chitosan (Ch)-based fibrous materials containing an ionizable model drug, 8-hydroxyquinoline-5-sulfonic acid (SQ), were successfully fabricated by electrospinning. Complexes between the components of the crosslinked PVA/Ch/SQ mats and Cu2+ and Fe3+ ions were formed. The coordination of these ions in the mats was examined by electron paramagnetic resonance spectroscopy (EPR). The microbiological screening against S. aureus and C. albicans revealed that both the incorporation of SQ in the mats and the complexation with Cu2+ and Fe3+ imparted to these materials antibacterial and antifungal activities. Moreover, the SQ-containing mats and their complexes displayed good cytotoxicity against human cervical HeLa tumor cells. The most prominent was the cytotoxicity of the Cu2+ complex of the mats. The combined antibacterial, antifungal and in vitro antitumor activities render these novel materials promising candidates for wound dressing applications and for application in the local treatment of cervical tumors.