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Polymeric derivatives of poly-N-vinylpyrrolidone containing different amounts of linker carboxylate ligands (partially hydrolyzed poly-N-vinylpyrrolidone with 5 mol% COOH groups and copolymers of N-vinylpyrrolidone with other monomers) were synthesized. The following copolymers were obtained: N-vinylpyrrolidone/crotonic acid and N-vinylpyrrolidone/N-vinylamidoanthanoic acid (containing 16 and 50 mol% COOH-groups). Metal-polymer complexes (MPC) with varying europium content were prepared through the interaction of the obtained polymers with equimolar amounts of hydroxocomplex Eu(Phen)2(OH)3 (Phen = 1,10-phenanthroline). The polymers and MPC were characterized by elemental analysis, IR, UV-vis spectroscopy and photoluminescence; their cytotoxicity toward living cells was estimated. All the obtained MPC exhibited photoluminescence with higher intensity than that of the reference complex Eu(Phen)2Br3. The dependence of luminescence intensity on the content of metallocenters in MPC was demonstrated. The relative quantum yield of luminescence was found to decrease with increasing europium content in MPC. It was shown that none of the polymers under investigation exhibited cytotoxicity. Furthermore, the presence of the polymeric anion in MPC contributed to a sharp decrease in the toxicity of metallocenter [Eu(Phen)2]3+solv. The MPC based on the N-vinylpyrrolidone/N-vinylamidoanthanoic acid copolymer exhibited no cytotoxicity within the entire investigated concentration range. [ABSTRACT FROM AUTHOR]

The aim of this study was to investigate the potential of upcycling Expanded Polystyrene (EPS) waste collected from food packaging into a membrane for microalgae harvesting, in which membrane filtration often challenges fouling and pore blocking. The target species is Spirulina platensis, with Chlorella vulgaris as a comparison agent. The membrane was fabricated from used Styrofoam, which typically ends up as single-use food packaging waste. In this study, PVP was used as an additive at varying concentrations, from 2 wt.% to 8 wt.%. The experimental results indicated that despite varying PVP concentrations, all EPS waste membranes exhibited near-complete recovery of Spirulina platensis biomass extraction. Despite the similar harvesting efficiency, EPS/PVP-8 exhibited the largest flux of 970.5 LMH/Bar, which is twice the value of the pristine EPS waste membrane. All membranes were hydrophilic; however, hydrophobicity increased with PVP concentration. SEM micrographs revealed that PVP enlarged the membrane surface pores and improved connectivity within the membrane's structure, ensuring efficient flow. The EPS waste membrane offers promising insights for sustainable materials and wastewater treatment. The upcycling of EPS waste into flat sheet membranes not only addresses the problem of Styrofoam waste accumulation but also paves the way to transform waste into valuable products. [ABSTRACT FROM AUTHOR]

This study synthesized chitosan-alginate-polyvinylpyrrolidone and applied it for Cr(VI) removal. Characterization was carried out using FTIR, TGA, N2 adsorption, 1H NMR, and FE-SEM. FTIR spectra show peaks at 1415 cm− 1, 1323 cm− 1, 1029 cm− 1, and 448 cm− 1, which are COO, C-N, C-O, and N-C = O groups. The surface area of CsAgPVP was 20.42 m2/g. The pore size of CsAgPVP was 5.36 nm. Field emission shows the C, O, N, and Na. The optimum conditions CsAgPVP dor adsorption Cr(VI) were 50 ppm, 360 min, and pH 4. It uses adsorption isotherm and kinetic to show the Langmuir model and pseudo-second-order. The CsAgPVP adsorption process is assumed homogeneous and considered as chemisorption. Adsorption capacity shows 208.67 mg/g. It uses a regeneration study of removal percentage up to 90% in the fourth cycle. The removal percentage in real sample mine wastewater and waste acid laboratories was 80% and 72%. [ABSTRACT FROM AUTHOR]

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The development of new catalytic systems based on cobalt and iron compounds for the production of oxygen-containing compounds is an urgent task of chemical technology. The purpose of this work is the synthesis of CoFe2O4 stabilized with polyvinylpyrrolidone (PVP), the study of the catalyst by physico-chemical research methods, and the determination of the effectiveness of the CoFe2O4/PVP catalyst in the phenol oxidation reaction. In this work, magnetic composites CoFe2O4 and CoFe2O4 stabilized with polyvinylpyrrolidone were synthesized by co-deposition. A comparison of the characteristics of the properties of the synthesized cobalt (II) ferrite (CoFe2O4) and the composite material CoFe2O4/PVP based on it is carried out. The obtained samples were examined using X-ray phase analysis (XRD), the Debye–Scherrer method, scanning electron microscopy (SEM), Mossbauer and IR Fourier spectroscopy, as well as thermogravimetric analysis (TGA). The textural properties were determined based on the analysis of nitrogen isotherms. The catalytic properties of the synthesized materials in the process of phenol oxidation in the presence of hydrogen peroxide are considered. The analysis of the reaction mixtures by HPLC obtained by the oxidation of phenol in the presence of a CoFe2O4/PVP catalyst showed a decrease in the concentration of phenol in the first 15 min of the process (by 55–60%), and then within 30 min, the concentration of phenol decreased to 21.83%. After 2 h of the process, the conversion of phenol was already more than 95%. The final sample after the reaction contained 28% hydroquinone and 50% benzoquinone. It was found that the synthesized magnetic composites exhibit catalytic activity in this process. [ABSTRACT FROM AUTHOR]

In the present study, electrospinning of polyvinylpyrrolidone (PVP) and polydiacetylene (PDA) with pomegranate peel (PG) extract was investigated for the preparation of smart and antibacterial nanofibers. Briefly, PDA-PVP solutions were firstly prepared at two different ratios and electrospun under different conditions. Based on the SEM results, the 1:3 ratio of PDA:PVP nanofibers, with an average fiber diameter of 130 ± 40 nm, electrospun at a voltage of 15 kV, feeding rate of 0.5 ml/h and collector distance of 15 cm was selected as the optimal conditions. The addition of PG resulted in an increase in the diameter of the fibers. The color of the electrospun fibers was altered from blue to red due to changes in either temperature or pH or exposure to different solvents. The antibacterial test showed high antimicrobial activity of the fibers loaded with PG extract against both S. aureus and E. coli. MTT assay and cell attachment also validated the biocompatibility of the fabricated nanofibers. Thus, the prepared smart PG-loaded nanofibers had a high potential to be used in wound dressing applications. [ABSTRACT FROM AUTHOR]

The recent progress in nanofiber research has demonstrated the potential for improving the physical properties of materials through the integration of graphene nanoplatelets (GNP). This study involves the synthesis and characterization of novel GNP-infused polyvinylpyrrolidone (PVP) electrospun nanofibers. The required precursor solution was prepared using dimethylformamide (DMF) as a solvent, and that included 1.5wt.% concentrations of GNP with 20 wt.% of PVP in 10mL of DMF solution. The investigation using scanning electron microscopy (SEM) and transmission electron microscopy (TEM) showed the morphology of the fibers with the distribution of graphene nanoplatelets. The zeta potential analysis demonstrates that the GNP/PVP nanofibers exhibit significant stability across a wide pH range, particularly in highly acidic and basic conditions. The thermogravimetric analysis (TGA) analysis showed exceptional thermal stability, with minimal weight loss until 300–400∘C. The degradation of the PVP matrix was observed beyond 400∘C. The results of the study show that GNP/PVP nanofibers have significant potential for specific applications in thermal management and energy storage under controlled temperature conditions. [ABSTRACT FROM AUTHOR]

The progression of membrane technology fundamentally depends on a deep understanding of the rheological properties of polymeric solutions, particularly for producing high-performance membranes. This research investigates the rheological behavior of polyphenylsulfone (PPSU) solutions containing organic additives – namely polyethylene glycol (PEG) and polyvinylpyrrolidone (PVP) – in N-Methyl-2-pyrrolidone (NMP) solvent, and their crucial role in membrane manufacturing. Using a rheometer, we analyzed the impact of different PPSU concentrations (10 to 30 wt.%), shear rates (0 to 100 1/s), and temperatures (20°C to 50°C) on the solutions’ rheological properties. The study also evaluated the effects of adding 5 wt.% PEG and PVP to PPSU solutions. Findings indicated that pure PPSU solutions had lower viscosities compared to those modified with PVP, while PEG addition resulted in even higher viscosities. A rise in temperature significantly lowered viscosities across all solutions, highlighting the importance of temperature in controlling polymer solution fluidity. Shear stress consistently demonstrated a linear relationship with shear rate, indicating shear-thinning behavior. This study illuminates how polymer concentration, organic additives, and temperature critically influence the rheological properties of PPSU solutions, emphasizing their importance in enhancing membrane fabrication for improved performance and efficiency. [ABSTRACT FROM AUTHOR]

Silver nanowires (AgNWs) have excellent flexibility, unique optical transmittance and high conductivity. The polyol process is appropriate for preparing AgNWs due to its simplicity, effectiveness, low cost, and high yield. This work aims to investigate the effect of preparation parameters of the polyol process on the silver nanowires properties. The parameters include the controlling agent, molecular weight of the polyvinylpyrrolidone (PVP), the temperature, and the reducing agent. The amount of silver nanoparticles formed during preparation was used to determine the optimum preparation conditions. The transmission electron microscope (TEM) images showed minimal amount of Ag nanoparticles when using mixed molecular weight of PVP-40K, and PVP-1.3M at 150 °C with the assistance of copper chloride as a controlling agent. The prepared AgNWs had an average length of 3.7 µm and aspect ratio of 15.3. The fabricated electrodes were characterized using a scanning electron microscope (SEM) and four probe resistivity measurements. The electrical measurement of the AgNWs electrodes indicated that the surfactant thickness is a critical parameter in having low sheet resistance electrodes. Also, the optical transmission was affected by the amount of nanoparticles. The prepared electrode with high concentration of AgNWs and a minimal amount of nanoparticles exhibited 80% optical transmission. [ABSTRACT FROM AUTHOR]

The recyclable paper based on photochromic materials not only reduces the pollution in the paper manufacture process, but also reduces the pollution caused by the use of ink, which receives wide attention. In this paper, a series of phosphomolybdic acid–phosphotungstic acid/ZnO/polyvinylpyrrolidone (PMoA-PWA/ZnO/PVP) hybrid films, which had different ratio of PMoA/PWA, was prepared by the ultrasonic composite method. The results indicated that the hybrid film prepared when the ratio of PMoA to PWA was 3 had the best photochromic performance. In this system, ZnO was the photosensitizer, while PMoA/PWA was the chromophore. The photochromic mechanism of the PMoA-PWA/ZnO/PVP hybrid film was based on the photogenerated electron transfer mechanism. ZnO generated photoelectron under the excitation of visible light, then PMoA and PWA obtained the photoelectron and produced photoreduction reaction to generate heteropolyblue. The visible light photochromic paper was prepared by loaded PMoA-PWA/ZnO/PVP hybrid film (A3) on A4 paper. Application tests showed that the prepared paper had extremely stable, excellent and reversible visible light photochromic properties, whether it was printing patterns or words, and could replace ordinary paper to realize the reuse of paper. [ABSTRACT FROM AUTHOR]

Although titanium and its alloys are widely used as dental implants, they cannot induce the formation of new bone around the implant, which is a basis for the functional integrity and long-term stability of implants. This study focused on the functionalization of the titanium/titanium oxide surface as the gold standard for dental implants, with electrospun composite fibers consisting of polyvinylpyrrolidone and Ca2+ ions. Polymer fibers as carriers of Ca2+ ions should gradually dissolve, releasing Ca2+ ions into the environment of the implant when it is immersed in a model electrolyte of artificial saliva. Scanning electron microscopy, energy dispersive X-ray spectroscopy and attenuated total reflectance Fourier transform infrared spectroscopy confirmed the successful formation of a porous network of composite fibers on the titanium/titanium oxide surface. The mechanism of the formation of the composite fibers was investigated in detail by quantum chemical calculations at the density functional theory level based on the simulation of possible molecular interactions between Ca2+ ions, polymer fibers and titanium substrate. During the 7-day immersion of the functionalized titanium in artificial saliva, the processes on the titanium/titanium oxide/composite fibers/artificial saliva interface were monitored by electrochemical impedance spectroscopy. It can be concluded from all the results that the composite fibers formed on titanium have application potential for the development of osteoinductive and thus more biocompatible dental implants. [ABSTRACT FROM AUTHOR]

Cannabigerol's (CBG) therapeutic effects are limited by its poor water solubility and low dissolution rate. To improve these properties, supercritical CO2-assisted atomization (SAA) was applied to produce coprecipitates, i.e., CBG nanoparticles coprecipitated in polyvinylpyrrolidone (PVP) microparticles. The experiments were performed by varying the CBG/PVP mass ratio (R) and the overall concentration of solutes CBG+PVP to study the influence of these parameters on particle morphology, particle size, and size distribution. Periodic dynamic light scattering (DLS) analysis was performed at regular time intervals to measure the size of CBG nanoparticles in PVP microparticles. It showed that CBG nanoparticles down to 105 nm were successfully produced through SAA. Dissolution tests were used to verify that a reduction of CBG particle size significantly increased its dissolution rate. In the liquid medium adopted, untreated CBG powder was released in 210 min, whereas CBG nanoparticles of 105 nm were completely dissolved in only 15 min. [ABSTRACT FROM AUTHOR]

• Using PVP for size and stability modulation for the formation of ZIF-67. • Development of a hybrid coating by utilizing MAO, LDH, and PVP-mediated ZIF-67. • The coating showed incredible multifunctional properties, with excellent stability. • Superior corrosion resistance was achieved (R p = 6.47 × 108). • Remarkable photocatalytic degradation of rhodamine b dye was also observed. Modulating metal-organic framework's (MOF) crystallinity and size using a polymer, in conjunction with a high surface area of layered double hydroxide, yields an effective strategy for concurrently enhancing the electrochemical and photocatalytic performance. In this study, we present the development of an optimized nanocomposite, denoted as 0.5PVP/ZIF-67, developed on AZ31 magnesium alloy, serving as an efficient and durable multifunctional coating. This novel strategy aims to enhance the overall performance of the porous coating through the integration of microarc oxidation (MAO), ZnFe LDH backbone, and ZIF-67 formation facilitated by the addition of polyvinylpyrrolidone (PVP), resulting in a three-dimensional, highly efficient, and multifunctional material. The incorporation of 0.5 g of PVP proved to be effective in the size modulation of ZIF-67, which formed a corrosion-resistant top layer, improving the total polarization resistance (R p = 8.20 × 108). The dual functionality exhibited by this hybrid architecture positions it as a promising candidate for mitigating environmental pollution, degrading 97.93 % of Rhodamine B dye in 45 min. Moreover, the sample displayed exceptional degradation efficiency (96.17 %) after 5 cycles. This study illuminates the potential of nanocomposites as electrochemically stable and photocatalytically active materials, laying the foundation for the advancements of next-generation multifunctional frameworks. [Display omitted] [ABSTRACT FROM AUTHOR]

Abstract Electrospinning is a specialized processing technique for the formation of submicron diameter fibers of polymeric and ceramic materials using an electrostatic field. The process has multiple advantages over other nano- and micro- fiber synthesis methods; however, generally suffers from very low fabrication speeds, making it undesirable for scalability. This work assesses the performance of a needle-less, self-contained, high throughput electrospinning system. It further compares the fiber fabrication rates obtained versus two single needle setups with different collectors: (i) a conventional single needle and flat plate geometry, and (ii) a single needle with a rotating collector geometry. Polyvinylpyrrolidone (PVP) in ethanol was used as the model material. The fabrication rate of the high throughput system “HTES” was measured at about 2.6 g/h and was about 15 times that collected of the flat plate. Comparing it to other systems reported in the literature also proved it to be a viable option for high throughput, lab scale electrospinning.

Modulating metal-organic framework's (MOF) crystallinity and size using a polymer, in conjunction with a high surface area of layered double hydroxide, yields an effective strategy for concurrently enhancing the electrochemical and photocatalytic performance. In this study, we present the development of an optimized nanocomposite, denoted as 0.5PVP/ZIF-67, developed on AZ31 magnesium alloy, serving as an efficient and durable multifunctional coating. This novel strategy aims to enhance the overall performance of the porous coating through the integration of microarc oxidation (MAO), ZnFe LDH backbone, and ZIF-67 formation facilitated by the addition of polyvinylpyrrolidone (PVP), resulting in a three-dimensional, highly efficient, and multifunctional material. The incorporation of 0.5 g of PVP proved to be effective in the size modulation of ZIF-67, which formed a corrosion-resistant top layer, improving the total polarization resistance (Rp = 8.20 × 108). The dual functionality exhibited by this hybrid architecture positions it as a promising candidate for mitigating environmental pollution, degrading 97.93 % of Rhodamine B dye in 45 min. Moreover, the sample displayed exceptional degradation efficiency (96.17 %) after 5 cycles. This study illuminates the potential of nanocomposites as electrochemically stable and photocatalytically active materials, laying the foundation for the advancements of next-generation multifunctional frameworks.

Abstract Silver nanowires (AgNWs) have excellent flexibility, unique optical transmittance and high conductivity. The polyol process is appropriate for preparing AgNWs due to its simplicity, effectiveness, low cost, and high yield. This work aims to investigate the effect of preparation parameters of the polyol process on the silver nanowires properties. The parameters include the controlling agent, molecular weight of the polyvinylpyrrolidone (PVP), the temperature, and the reducing agent. The amount of silver nanoparticles formed during preparation was used to determine the optimum preparation conditions. The transmission electron microscope (TEM) images showed minimal amount of Ag nanoparticles when using mixed molecular weight of PVP-40K, and PVP-1.3M at 150 °C with the assistance of copper chloride as a controlling agent. The prepared AgNWs had an average length of 3.7 µm and aspect ratio of 15.3. The fabricated electrodes were characterized using a scanning electron microscope (SEM) and four probe resistivity measurements. The electrical measurement of the AgNWs electrodes indicated that the surfactant thickness is a critical parameter in having low sheet resistance electrodes. Also, the optical transmission was affected by the amount of nanoparticles. The prepared electrode with high concentration of AgNWs and a minimal amount of nanoparticles exhibited 80% optical transmission.

The recyclable paper based on photochromic materials not only reduces the pollution in the paper manufacture process, but also reduces the pollution caused by the use of ink, which receives wide attention. In this paper, a series of phosphomolybdic acid–phosphotungstic acid/ZnO/polyvinylpyrrolidone (PMoA-PWA/ZnO/PVP) hybrid films, which had different ratio of PMoA/PWA, was prepared by the ultrasonic composite method. The results indicated that the hybrid film prepared when the ratio of PMoA to PWA was 3 had the best photochromic performance. In this system, ZnO was the photosensitizer, while PMoA/PWA was the chromophore. The photochromic mechanism of the PMoA-PWA/ZnO/PVP hybrid film was based on the photogenerated electron transfer mechanism. ZnO generated photoelectron under the excitation of visible light, then PMoA and PWA obtained the photoelectron and produced photoreduction reaction to generate heteropolyblue. The visible light photochromic paper was prepared by loaded PMoA-PWA/ZnO/PVP hybrid film (A3) on A4 paper. Application tests showed that the prepared paper had extremely stable, excellent and reversible visible light photochromic properties, whether it was printing patterns or words, and could replace ordinary paper to realize the reuse of paper.

AbstractA flexible formaldehyde sensor with high sensitivity was successfully fabricated by integrating palladium (Pd) nanoparticles, polyvinylpyrrolidone (PVP), multi-walled carbon nanotubes (MWCNTs) and nanocellulose (NC) into composite films. The flexible composite films were fabricated via vacuum filtration. The morphology, structure, composition, crystallinity, and functional group of as-fabricated sensing materials were characterized by scanning electron microscopy, transmission electron microscopy, electron probe microanalyzer, Raman spectroscopy, and Fourier transform infrared spectrometer. Pd nanoparticles-PVP-MWCNTs-NC (Pd-PVP-MWCNTs-NC) composite films exhibited an 11-fold increase in formaldehyde sensitivity compared to MWCNTs-NC composite films. The excellent sensing performances of Pd-PVP-MWCNTs-NC sensors were attributed to the combination of Pd nanoparticles and PVP. The enhanced sensitivity is attributed to the synergistic effect of the high electron transfer from formaldehyde molecule to Pd nanoparticles and swelling of PVP due to sorption of formaldehyde molecule. Pd-PVP-MWCNTs-NC sensors still maintained good response under bending angle up to 30° and 300 bending cycles. The results demonstrate that the Pd-PVP-MWCNTs-NC composite films are highly promising in terms of sensitivity and flexibility for sub-ppm level formaldehyde detection at room temperature. [ABSTRACT FROM AUTHOR]

Poor water solubility of drugs is a limiting factor for their bioavailability and pharmacological activity. Many approaches are known to improve drug solubility, and among them, the physical method, solid dispersions (SDs), is applied. SDs are physical mixtures of a drug and a carrier, sometimes with the addition of a surfactant, which can be obtained by milling, cryomilling, spray-drying, or lyophilization processes. In this study, solid dispersions with etodolac (ETD-SDs) were prepared by the milling method using different carriers, such as hypromellose, polyvinylpyrrolidone, copovidone, urea, and mannitol. Solubility studies, dissolution tests, morphological assessment, thermal analysis, and FTIR imaging were applied to evaluate the SD properties. It was shown that the ball-milling process can be applied to obtain SDs with ETD. All designed ETD-SDs were characterized by higher water solubility and a faster dissolution rate compared to unprocessed ETD. SDs with amorphous carriers (HPMC, PVP, and PVP/VA) provided greater ETD solubility than dispersions with crystalline features (urea and mannitol). FTIR spectra confirmed the compatibility of ETD with tested carriers. [ABSTRACT FROM AUTHOR]

Mesoporous hydroxyapatite (HA) is widely used in various applications, such as the biomedical field, as a catalytic, as a sensor, and many others. The aim of this work was to obtain HA powders by means of chemical precipitation in a medium containing a polymer—polyvinyl alcohol or polyvinylpyrrolidone (PVP)—with concentrations ranging from 0 to 10%. The HA powders were characterized by X-ray diffraction, Fourier transform infrared spectroscopy, atomic emission spectroscopy with inductively coupled plasma, electron paramagnetic resonance, scanning electron microscopy (SEM), and transmission electron microscopy (TEM). The specific surface area (SSA), pore volume, and pore size distributions were determined by low-temperature nitrogen adsorption measurements, and the zeta potential was established. The formation of macropores in powder agglomerates was determined using SEM and TEM. The synthesis in 10% PVP increased the SSA from 101.3 to 158.0 m2/g, while the ripening for 7 days led to an increase from 112.3 to 195.8 m2/g, with the total pore volume rising from 0.37 to 0.71 cm3/g. These materials could be classified as meso-macroporous HA. Such materials can serve as the basis for various applications requiring improved textural properties and may lay the foundation for the creation of bulk 3D materials using a technique that allows for the preservation of their unique pore structure. [ABSTRACT FROM AUTHOR]

This study presents the biosynthesis of a novel polyvinylpyrrolidone (PVP)-modified Fe2O3/Fe3O4 nanocomposite (NC) using an olive leaf extract. The synthesized nanocomposites exhibit dual functionality, highlighting enhanced photocatalysis and antioxidant activity, offering promising applications in environmental remediation and therapeutics. The process involves meticulous biosynthesis and PVP-mediated surface modification, confirmed by X-ray diffraction (XRD), transmission electron microscopy (TEM), Fourier transform infrared spectroscopy (FTIR), and UV–vis analysis. Both Fe2O3/Fe3O4 NC and Fe2O3/Fe3O4@PVP NC show spherical morphologies with average sizes of 21.7 nm and 30.1 nm, and optical bandgap energies of 1.8 eV and 1.34 eV, respectively. Photocatalytic activity assessments against amoxicillin antibiotic degradation under solar irradiation highlight the superior performance of PVP-modified nanocomposites, achieving an impressive 99% removal efficiency in 50 min compared to 84% for Fe2O3/Fe3O4 NC. Kinetic investigations reveal rate constants of 0.021 min− 1 and 0.0025 min− 1 for PVP-modified and unmodified nanocomposites, respectively, emphasizing the enhanced degradation rates. Optimization studies showcase the mass-dependent efficiency, with PVP-modified nanocomposites achieving a remarkable 91% removal rate of amoxicillin with a 7.5 mg catalyst. The recycling performance demonstrates sustained efficacy over five consecutive cycles, with only a slight decline from 99 to 97.5%. Moreover, the nanocomposites exhibited significant antioxidant activity, with Total Antioxidant Activity (TAC) values of 5.5 and 6.86 mg GAE/mg sample for Fe2O3/Fe3O4 NC and Fe2O3/Fe3O4@PVP NC, respectively. The environmentally synthesized PVP-modified Fe2O3/Fe3O4 NC showcases promising dual functionality, making them versatile candidates for efficient pollutant degradation and antioxidant applications in environmental and therapeutic domains. [ABSTRACT FROM AUTHOR]

Uveitis comprises a cluster of intraocular inflammatory disorders characterized by uncontrolled autoimmune responses and excessive oxidative stress leading to vision loss worldwide. In the present study, curcumin (CUR) was conjugated with polyvinylpyrrolidone (PVP) to form PVP-CUR nanoparticles with significantly elevated solubility and outstanding multiple radical scavenging abilities. In vitro studies revealed that PVP-CUR nanoparticles markedly mitigated oxidative stress and reduced apoptosis in a H 2 O 2 -induced human retinal pigment epithelial cell line (ARPE-19) and promoted phenotypic polarization from M1 to M2 in an LPS-induced human microglial cell line (HMC3). Further in vivo studies demonstrated the prominent therapeutic effects of PVP-CUR nanoparticles on experimental autoimmune uveitis (EAU), which relieved clinical and pathological progression, improved perfusion and tomographic manifestations of retinal vessels, and reduced blood–retinal barrier (BRB) leakage; these effects may be mediated by mitigating oxidative stress and attenuating macrophage/microglia-elicited inflammation. Notably, treatment with PVP-CUR nanoparticles was shown to regulate metabolite alterations in EAU rats, providing novel insights into the underlying mechanisms involved. Additionally, the PVP-CUR nanoparticles showed great biocompatibility in vivo. In summary, our study revealed that PVP-CUR nanoparticles may serve as effective and safe nanodrugs for treating uveitis and other oxidative stress- and inflammation-related diseases. [Display omitted] [ABSTRACT FROM AUTHOR]

A lightweight water-soluble core mold material for hollow shell composites was prepared by hot drying process with polyvinylpyrrolidone (PVP) aqueous solution as the adhesive and hollow glass microspheres as the matrix material. The effects of the content of adhesive and different treatment methods on the flexural strength, compressive strength and dissolution rate of the core mold were studied, and the microstructure of the core mold material was observed by scanning electron microscope. The results show that adhesive dosage of 40%, the flexural strength and compressive strength could reach up to 3.346 MPa and 3.499 MPa, with a water solubilization rate of 0.238 g/s. After the coupling agent treatment and high temperature treatment, the core mold strength and dissolution rate are improved, and the modification effect is good; small filler sizes can effectively fill the gap formed by matrix materials accumulation, improve the mechanical strength and affect the water solubility rate. The properties of water-soluble core can meet the requirements of resin transfer molding (RTM) and vacuum bag molding, which provides a solution for the integrated molding of profiled hollow profiles. [ABSTRACT FROM AUTHOR]

Gold nanoparticles (AuNPs) have great potential as biosensors for glucose detection due to their high sensitivity, as well as their extraordinary physical and chemical properties that improve compatibility with different biorecognition molecules, such as glucose oxidase (GOx). In this work the D-glucose quantification was determined by using the traditional technique based on biochemical reaction of GOx and AuNPs functionalized with polyvinylpirrolidone (PVP) polymer and the enzyme. The AuNPs-PVP-GOx nanocomplexes were characterized by ultraviolet-visible (UV-Visible), Infrared (FTIR), and Raman spectroscopies, as well as scanning electron microscopy (SEM), Z potential, dynamic light scattering (DLS), and thermogravimetry analysis (TGA). In general, these techniques showed significant differences after each functionalization stage with PVP and GOx, for instance it was observed: the presence of different functional groups, an increase of hydrodynamic diameter from 48.60 to 198.77 nm, a shift of the band absorption to larger wavelength, a change in the surface potential and weight loss, and in the morphology of the nanocomplex, which confirm the functionalization. In addition, the enzymatic activity of the AuNPs-PVP-GOx was confirmed through the detection of triiodide ions by UV-Visible spectrophotometry, coming from the oxidation reaction of iodide ions in the presence of H2O2. Furthermore, the nanocomplex synthesized by passive adsorption was evaluated as a possible biosensor for the quantification of D-glucose using a colorimetric assay, obtaining greater sensitivity than the traditional method. These findings indicate that PVP can be used as a linkage medium between AuNPs and GOx, which in turn can be used as a biosensor for the detection of D-glucose at low concentrations in biological fluids. [ABSTRACT FROM AUTHOR]

This paper presents the first scanning electron microscopy (SEM)‐based DNA imaging in biological samples. This novel approach incorporates a metal‐free electro‐stain reagent, formulated by combining DNA‐binding proteins and synthetic polymers to enhance the visibility of 2‐nm‐thick DNA under SEM. Notably, DNA molecules stain with proteins and polymers appear as dark lines under SEM. The resulting DNA images exhibit a thickness of 15.0±4.0 nm. As SEM is the primary platform, it integrates seamlessly with various chemically functionalized large surfaces with the aid of microfluidic devices. The approach allows high‐resolution imaging of various DNA structures including linear, circular, single‐stranded DNA and RNA, originating from nuclear and mitochondrial genomes. Furthermore, quantum dots are successfully visualized as bright labels that are sequence‐specifically incorporated into DNA molecules, which highlights the potential for SEM‐based optical DNA mapping. In conclusion, DNA imaging using SEM with the novel electro‐stain offers electron microscopic resolution with the ease of optical microscopy. [ABSTRACT FROM AUTHOR]

Colloidal semiconductor nanoparticles (NPs) represent an emergent state of matter with unique properties, bridging bulk materials and molecular structures. Their distinct physical attributes, such as bandgap and photoluminescence, are intricately tied to their size and morphology. Ligand passivation plays a crucial role in shaping NPs and determining their physical properties. Ligand exchange (LE) offers a versatile approach to tailoring NP properties, often guided by Pearson's Hard–Soft Acid–Base theory. Lead sulfide (PbS), a semiconductor of considerable interest, exhibits size-dependent tunable bandgaps from the infrared to the visible range. Here, we present two methods for synthesizing water-soluble, polyvinylpyrrolidone (PVP)-coated PbS NPs. The first involves direct synthesis in an aqueous solution while utilizing PVP as the surfactant for the formation of nano-cubes with a crystal coherence length of ~30 nm, while the second involves LE from octadecylamine-coated PbS truncated nano-cubes to PVP-coated PbS NPs with a crystal coherence length of ~15 nm. Multiple characterization techniques, including X-ray diffraction, transmission electron microscopy, Fourier-transform infrared spectroscopy, and thermal gravimetric analysis, confirmed the results of the synthesis and allowed us to monitor the ligand exchange process. Our findings demonstrate efficient and environmentally friendly approaches for synthesizing PVP-coated PbS NPs. [ABSTRACT FROM AUTHOR]

Dasatinib (DAS) is a second‐generation tyrosine kinase inhibitor used in the treatment of Philadelphia chromosome‐positive chronic myeloid leukemia and acute lymphoblastic leukemia. Nevertheless, this drug is hindered by poor gastrointestinal absorption and limited bioavailability, primarily attributable to its low aqueous solubility. To improve its properties, solid dispersions of DAS within a matrix of the hydrophilic polymer polyvinylpyrrolidone (PVP) are prepared by cogrinding in a vibrational ball mill at various drug‐to‐polymer ratios. The prepared solid dispersions are thoroughly characterized by several methods to verify the drug's amorphization and enhanced wettability as a result of successful mechanochemical activation. Fluidized bed melt granulation and traditional tableting are used to prepare tablets of 8 mm diameter with strictly defined aimed properties. Characterization of tablets includes testing their hardness, disintegration, and in vitro dissolution. The in vitro release profiles reveal a significant improvement in the release rate of DAS from tablets containing solid dispersion with the highest polymer ratio when compared with those containing untreated DAS or solid dispersions with a low polymer ratio. The results confirm the significant effect of the PVP ratio in solid dispersions on the surface characteristics and dissolution rate of DAS. [ABSTRACT FROM AUTHOR]

This study involved the preparation of the Saudi Arabian Cassia angustifolia Vahl methanolic extract and the production of polyvinylpyrrolidone (PVP) nanofibers that contained the Saudi Arabian C. angustifolia Vahl methanolic extract. The reason for using polyvinylpyrrolidone is its bioactivity and its physical and chemical properties. The structure and characterization of the newly synthesized nanofiber were confirmed using the Fourier-transform infrared (FTIR) spectrum, elemental analysis, scanning electron microscopy (SEM) image, N2 adsorption–desorption curve, hydrophilicity, compressive strength, and flexural strength. The biological activity, including anticancer properties against skin cancer cells and bone cancer cells and antibacterial activity against Gram-positive and Gram-negative strains, was assessed. The average diameter and the specific surface area of the synthesized polyvinylpyrrolidone nanofibers containing the Saudi Arabian Cassia angustifolia Vahl methanolic extract were 87 nm and 1,108 m² /g, respectively. High hydrophilicity compared to polyvinylpyrrolidone (contact angle of synthetic nanofibers was 21° and for polyvinylpyrrolidone was 52°), high compressive strength compared to polyvinylpyrrolidone (61.23 N/mm² and 34.52 N/mm², respectively), and high flexural strength compared to polyvinylpyrrolidone (16.1 N/mm2 and 11.4 N/mm², respectively) were other characteristics of the synthesized polyvinylpyrrolidone nanofibers containing the Saudi Arabian Cassia angustifolia Vahl methanolic extract. In the biological activities of the synthesized nanofiber, unique properties were observed. Regarding the anticancer activity, the IC50 values against skin cancer cells and bone cancer cells were observed to be 19.59 μg/mL and 29.57 μg/mL, respectively. For the antimicrobial activity, the MIC value between 4 and 128 mg/mL was observed. The biological activities of the synthesized polyvinylpyrrolidone nanofibers containing the Saudi Arabian Cassia angustifolia Vahl methanolic extract were higher than those of the Saudi Arabian Cassia angustifolia Vahl methanolic extract. The biological properties can be enhanced by various factors, including the high specific surface area of the synthesized nanofiber. [ABSTRACT FROM AUTHOR]

In this study, montmorillonite (MMT), used as filler, was modified with two different silane agents ((3-aminopropyl)triethoxysilane (APTES) and (3-glycidoxypropyl)trimethoxysilane (GPTMS)) to increase the interfacial interaction with the organic phase and ensure homogeneous distribution in the polymer matrix. As polymer matrix, polycaprolactone (PCL), a synthetic polymer with biodegradable and biocompatible properties, and polyvinylpyrrolidone (PVP), a biocompatible and hydrophilic polymer, were used together and biomaterials were produced by solution casting method. The morphological, physicochemical and mechanical properties of the biomaterials proposed for use as scaffolds for bone tissue engineering were characterized by atomic force microscopy (AFM), Fourier transform infrared spectroscopy (FTIR), X-ray diffractometry (XRD), contact angle analysis, water absorption capacity analysis and mechanical analysis. AFM results showed that the roughness of the PCL/PVP polymer matrix decreased from 0.507 µm to 0.171 µm with the addition of unmodified MMT and to 0.160 µm with the addition of MMT-APTES. The highest roughness ratio was found to be 0.530 µm in GPTMS-modified MMT doped biomaterials. When contact angle values and water absorption capacities were compared, it was observed that APTES and GPTMS-modified MMT doped biomaterials with contact angles of 68.4° and 59.7° were more hydrophilic than the biomaterial without MMT and the water absorption capacity was 125% and 144% higher than the polymer matrix without MMT and the unmodified biomaterial. In conclusion, this preliminary study suggests that APTES-modified MMT doped PCL/PVP biomaterials can be used as tissue scaffolds in the treatment of bone tissue damage. [ABSTRACT FROM AUTHOR]

Coaxial astragaloside (AS)/polyvinylpyrrolidone (PVP)/polylactic acid (PLA) nanofiber functional dressings (AS/PVP/PLA) were prepared by coaxial electrostatic spinning technique. The micro-morphology, wettability, water vapor transmission rate and other properties of nanofiber dressings were characterized. The antioxidant capacity, antibacterial effect, and pro-diabetic chronic wound healing effect of the nanofiber dressings were also investigated. Results showed that the coaxial AS/PVP/PLA nanofiber functional dressing had an obvious core-shell structure and a smooth fiber surface, with a fiber diameter of (480±240) nm, a contact angle of (88.73±1.07)°, a water vapor transmission rate of (1660.42±80.61) g/(m²·d), and a free radical scavenging rate of 47%. AS/PVP/PLA nanofiber functional dressing significantly inhibited the growth of Escherichia coli and Staphylococcus aureus, and had a certain pro-healing effect on diabetic chronic wounds. The nanofiber dressings had good morphology and met the requirements, and had the potential to be developed as dressings for diabetic chronic wound healing. [ABSTRACT FROM AUTHOR]

Background: New versions of the polyester polymer alloy (PEPA) membrane have appeared over the years, with increases in both the pore size and the amount of polyvinylpyrrolidone (PVP) to optimize hydrophilicity performance. This study aimed to assess the efficacy of the most recently developed PEPA dialyzer, the FDY series, in hemodialysis (HD) modality in terms of uremic toxin removal and albumin loss and to compare it with that of several high‐flux dialyzers currently used in HD and post‐dilution hemodiafiltration (HDF) treatments. Methods: A prospective study was carried out in 21 patients. All patients underwent six dialysis sessions with the same routine dialysis parameters; only the dialyzer and/or the dialysis modality varied: FX80 in HD, FDY 180 in HD, Clearum HS17 in HDF, Elisio 19H in HDF, Vitapes 180 in HDF, and FX80 in post‐dilution HDF. The reduction ratios (RR) of urea, creatinine, ß2‐microglobulin, myoglobin, κFLC, prolactin, α1‐microglobulin, α1‐acid glycoprotein, λFLC, and albumin were compared intraindividually. Dialysate albumin loss was also measured. Results: Both membranes FDY and FX80 are high‐flux dialyzers and are applied here in high‐flux HD. The average RR of β2‐microglobulin was slightly lower in the two HD treatments than in the HDF treatments. Comparison of dialysis treatments revealed that the PEPA FDY dialyzer in the HD modality was more effective than the FX80 dialyzer in high‐flux HD and was as effective as post‐dilution HDF, especially in terms of myoglobin, κFLC, prolactin, α1‐microglobulin, and λFLC RRs. The FDY treatments obtained similar albumin RR in blood and slightly higher dialysate albumin loss, although the values were clinically acceptable. Conclusions: The most recently developed PEPA dialyzers in the HD modality were as effective as all treatments in the HDF modality and were clearly superior to high‐flux helixone HD treatment. These results confirm that this dialyzer should be categorized within the medium cut‐off (MCO) membrane classification. [ABSTRACT FROM AUTHOR]

This study aimed to incorporate virgin coconut oil (VCO) into polyvinylpyrrolidone (PVP) fiber matrix using the rotary force spinning (RFS) method and evaluated their physicochemical properties, antioxidant activity, and release behavior. The PVP/VCO fibers were produced by varying the weight ratios of PVP:VCO of 10:2, 10:3, 10:4, and 10:5. Scanning electron microscopy (SEM) analysis revealed smooth, defect-free, and bead-free PVP/VCO fibers with diameters ranging from (1.28 ± 0.06) to (2.17 ± 0.41) µm. Fourier-transform infrared spectroscopy (FTIR) confirmed the successful loading of VCO into the PVP fiber matrix. X-ray diffraction (XRD) analysis indicated the amorphous nature of the PVP/VCO fibers. Differential scanning calorimetry (DSC) analysis demonstrated that PVP/VCO fibers exhibited higher thermal stability compared to pure PVP and VCO. The antioxidant activity of VCO, with IC50 value of (1.56 ± 0.30) mg mL−1, was not significantly altered by the incorporation of VCO into the PVP fibers. The PVP/VCO fibers exhibited IC50 values ranging from (1.58 ± 0.06) to (2.25 ± 0.09) mg mL−1. The release profile of VCO from the PVP/VCO fibers was influenced by the fiber diameter, with the samples containing weight ratios of 10:4 and 10:5 demonstrating optimal characteristics such as smaller diameter, higher thermal stability, higher antioxidant activity, and prolonged release behavior. This study holds promise for the development of novel oral delivery systems for VCO and contributes to the expanding research on the utilization of fiber structures in food supplement and drug delivery applications. [ABSTRACT FROM AUTHOR]

Silver nanoparticles (AgNP) are widely used globally due to their numerous properties, mainly because of their antimicrobial activity. However, the need for further regulations and legislation regarding their presence in products has led to concerns about their biosecurity, necessitating relevant biological studies at different levels. The present work aimed to evaluate the effect of the polyvinylpyrrolidone (PVP)-coated AgNP on the small intestine contraction and other mediators involved and the mediators involved (nitric oxide and serotonin) in an ex vivo model. Intestinal segments (duodenum, jejunum, and ileum) were treated in the presence and absence of five cumulative, increasing concentrations of AgNP (0.01, 0.1, 1, 10, and 100 µg/mL) and three individual concentrations of PVP-coated AgNP (0.01, 1, and 100 µg/mL), showing a transient decrease in the contractile effect in the small intestine segments treated with cumulative, increasing concentrations. This effect did not allow the isolated small intestine rings to return to their contractile basal level, and it was associated with an increase in nitric oxide (NO) production and variations in the amount of serotonin. A similar effect was observed at individual AgNP administrations but with a lesser influence on NO production. These results show that AgNP, in the function of the administration (cumulative or individual) and the segment type, can modify the contraction of the small intestine, mediated in part by NO and exerting a differential pattern in the amount of serotonin. Histological analysis revealed that specific morphological alterations induced by AgNP, such as necrosis and villi detachment, were more evident in the ileum segment. Furthermore, the accumulation of silver was observed in the small intestine villi, which could determine the physiological effects exerted upon the intestinal contraction associated with the release of a specific mediator like NO production and the presence of serotonin. These findings suggest that the small intestine is an essential target of the actions induced by AgNP, which could be ingested and reach this conduit because of the consumption of products containing these materials, modifying the intestinal motility that influences the efficiency of nutrient absorption--aspects that need to be explored and investigated in the short, medium, and long terms. [ABSTRACT FROM AUTHOR]

Due to the growing concerns surrounding microbial contamination and food safety, there has been a surge of interest in fabricating novel food packaging with highly efficient antibacterial activity. Herein, we describe novel photodynamic antibacterial konjac glucomannan (KGM)/polyvinylpyrrolidone (PVP) nanofibers incorporated with lignin-zinc oxide composite nanoparticles (L-ZnONPs) and curcumin (Cur) via electrospinning technology. The resulting KGM/PVP/Cur/L-ZnONPs nanofibers exhibited favorable hydrophobic properties (water contact angle: 118.1°), thermal stability, and flexibility (elongation at break: 241.9%). Notably, the inclusion of L-ZnONPs and Cur endowed the nanofibers with remarkable antioxidant (ABTS radical scavenging activity: 98.1%) and photodynamic antimicrobial properties, demonstrating enhanced inhibitory effect against both Staphylococcus aureus (inhibition: 12.4 mm) and Escherichia coli (12.1 mm). As a proof-of-concept study, we evaluated the feasibility of applying nanofibers to fresh strawberries, and the findings demonstrated that our nanofibers could delay strawberry spoilage and inhibit microbial growth. This photodynamic antimicrobial approach holds promise for design of highly efficient antibacterial food packaging, thereby contributing to enhanced food safety and quality assurance. [ABSTRACT FROM AUTHOR]

The aim of this study was to investigate whether it is possible to prevent oolemma lysis after Piezo-assisted intracytoplasmic sperm injection (Piezo-ICSI) caused by abnormal membrane rupture. A total of 489 mature oocytes were obtained from 85 patients who underwent Piezo-ICSI in an infertility clinic. Inseminated oocytes were classified into the following two groups: normal rupture and abnormal rupture, and a portion of abnormally ruptured oocytes was randomly exposed to 7% PVP solution. Normal fertilization rate, degeneration rate, proportion of high-quality embryos on day 3, blastocyst formation, and morphologically high-quality blastocysts were compared. Abnormal rupture was defined as cytoplasmic membrane rupture before piezo pulse driving. Among the abnormal rupture groups, the normal fertilization and degeneration rates were compared between the high-stretched (ruptured at ≥ 50% during oocyte membrane stretching) and low-stretched (< 50% position) oocytes. The degeneration rate was significantly higher in abnormally ruptured oocytes than in normally ruptures oocytes (14.3% vs 1.3%, p < 0.001), and there was no significant difference in embryonic development after fertilization. PVP treatment immediately after oolemma rupture significantly decreased the degeneration rate (6.0% vs 19.7%, p = 0.031) and increased the normal fertilization rate. Similarly, there were no significant differences in the developmental potential. Furthermore, pregnancy outcome data showed no significant differences in pregnancy and live birth rates. The degeneration rate was reduced by treating low-stretched oocytes with PVP. Exposure to polyvinylpyrrolidone (PVP) immediately after abnormal membrane rupture represents an effective strategy to prevent oocyte degeneration. This is the first study to propose a strategy for the prevention of oocyte degeneration in Piezo-ICSI. These findings are expected to reduce the oocyte degeneration rate and increase normal fertilization rate as well as assist patients who can only acquire oocytes with weak plasma membranes. [ABSTRACT FROM AUTHOR]

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The MOF‐5@clinoptilolite (MOF@CP) composites are successfully synthesized using polyvinylpyrrolidone (PVP) for adsorption separation of CO2/CH4, CO2/N2, and CH4/N2. The effects of the PVP amounts on the dispersity of MOF‐5 on CP random lamellas of the MOF@CPs are evaluated via various characterizations. Meanwhile, their single‐component gas adsorption isotherms, breakthrough experiments, and cycling test are measured. The results elucidate that the used PVP amount has a significant influence on the particle size and the uniformity of MOF‐5 dispersed on CP random lamellas. The MOF‐5‐loaded amount in MOF@CP is estimated to be up to 42.52 wt.%. Especially, the surface fractal evolutions indicated the surfaces of MOF@CP became from rough to smooth with the increase of PVP. The CO2/CH4, CO2/N2, and CH4/N2 selectivity factors of MOF@CP are higher than that of CP, displaying a better separation performance. Their cycling test revealed that MOF@CPs could be used repetitively, highlighting efficiency for CO2 and CH4 separation. Meanwhile, the MOF‐5@CP stability under moisture is preliminarily investigated, showing higher moisture resistance stability than MOF‐5. Additionally, the grand canonical Monte Carlo simulations demonstrated the adsorption separation mechanism of the prepared MOF@CPs. [ABSTRACT FROM AUTHOR]

Electrospun nanofibers have been used as wound dressings to protect skin from infection and promote wound healing. In this study, we developed polyvinylpyrrolidone (PVP)/silicon dioxide (SD) composite nanofibers for the delivery of probiotic Saccharomyces cerevisiae (SC), which potentially aids in wound healing. PVP/SD composite nanofibers were optimized through electrospinning, and bead-free nanofibers with an average diameter of 624.7 ± 99.6 nm were fabricated. Next, SC, a wound-healing material, was loaded onto the PVP/SD composite nanofibers. SC was encapsulated in nanofibers, and nanofibers were prepared using SC, PVP, SD, water, and ethanol in a ratio of 3:4:0.1:4.8:1.2. The formation of smooth nanofibers with protrusions around SC was confirmed using SEM. Nanofiber dressing properties were physicochemically and mechanically characterized by evaluating SEM, DSC, XRD, and FTIR images, tensile strength, and elongation at break. Additionally, a release test of active substances was performed. The absence of interactions between SC, PVP, and SD was confirmed through physicochemical evaluation, and SEM images showed that the nanofiber dressing contained SC and had a porous structure. It also showed a 100% release of SC within 30 min. Overall, our study showed that SC-loaded PVP/SD composite nanofibers prepared using the electrospinning method are promising wound dressings. [ABSTRACT FROM AUTHOR]

Microneedles offer minimally invasive, user-friendly, and subcutaneously accessible transdermal drug delivery and have been widely investigated as an effective transdermal delivery system. Ibuprofen is a common anti-inflammatory drug to treat chronic inflammation. It is crucial to develop microneedle patches capable of efficiently delivering ibuprofen through the skin for the effective treatment of arthritis patients requiring repeated medication. In this study, the mechanical properties of a new type of polymer microneedle were studied by finite element analysis, and the experimental results showed that the microneedle could effectively deliver drugs through the skin. In addition, a high ibuprofen-loaded microneedle patch was successfully prepared by micromolding and subjected to evaluation of its infrared spectrum morphology and dissolve degree. The morphology of microneedles was characterized by scanning electron microscopy, and the mechanical properties were assessed using a built linear stretching system. In the in-vitro diffusion cell drug release test, the microneedle released 85.2 ± 1.52% (210 ± 3.7 μg) ibuprofen in the modified Franz diffusion within 4 h, exhibiting a higher drug release compared to other drug delivery methods. This study provides a portable, safe and efficient treatment approach for arthritis patients requiring daily repeated medication. [ABSTRACT FROM AUTHOR]

In this study, a new hybrid material was created that exhibits excellent adsorption performance and high stability. POT‐PVP/MgF/CS‐OXSWCNTs NCs were synthesized using a three‐step approach. The process involved the chemical polymerization of poly(o‐toluidine)‐polyvinylpyrrolidone (POT‐PVP) with MgFe2O4 nanoparticles (MgF NPs) and chitosan‐oxidized single‐wall carbon nanotubes (CS‐OXSWCNTs). The synthesis process involved the use of an egg white method to synthesize MgF NPs and cross‐linking chitosan with OXSWCNTs using glutaraldehyde (GA) to obtain CS‐OXSWCNTs. The POT‐PVP copolymer was then used to coat MgF NPs and CS‐OXSWCNTs NCs. The successful synthesis of the NCs with strong component interaction was confirmed by several characterization techniques, including X‐ray diffraction spectroscopy (XRD), Fourier‐transform infrared spectroscopy (FTIR), and Raman spectroscopy. Microscopy analysis using scanning electron microscopy (SEM) and transmission electron microscopy (TEM) verified that the POT‐PVP copolymer had properly coated the MgF NPs and CS‐OXSWCNTs NCs. The N2 adsorption–desorption isotherm verified that the specific surface area of NCs had increased with the addition of MgF NPs and CS‐OXSWCNTs NCs. Furthermore, the composite structure greatly improved the thermal stability of POT‐PVP/MgF/CS‐OXSWCNTs NCs. To evaluate how well the nanocomposites (NCs) eliminated pollutants, an artificially produced toxic effluent that contained acid red dye (A.R) was applied. To investigate their impact on dye removal, several parameters were changed, including pH, adsorbent dosage, time, temperature, and ionic strength. The POT‐PVP/MgF/CS‐OXSWCNTs NCs showed a higher removal rate based on a greater surface area, stability, and conducting power than MgF NPs and POT‐PVP. It was found that 25 mg L−1 and 7.5 mg were the optimal dye concentration and adsorbent dosage, respectively. The POT‐PVP/MgF/CS‐OXSWCNTs NCs achieved 99.46% removal efficiency at an acidic pH of 2. The NCs were found to have a maximum dye adsorption capacity of 107.4 mg g−1, and the adsorption process followed the pseudo‐second‐order kinetics. Thermodynamic analyses revealed that the dye adsorption onto POT‐PVP/MgF/CS‐OXSWCNTs NCs was endothermic, implying a spontaneous and physical adsorption mechanism. It can be inferred from these results that POT‐PVP/MgF/CS‐OXSWCNTs NCs are useful for eliminating dye pollutants from water. [ABSTRACT FROM AUTHOR]

This study aims to investigate the fracture, molecular mobility and crystallization behaviors of amorphous griseofulvin (GSF) in the presence of polyvinylpyrrolidone (PVP). In the presence of 10%(w/w) PVP K90, the fracture resistance of griseofulvin was greatly improved. Compared with the pure GSF system, the average fracture temperature of the griseofulvin–PVP K90 system was decreased to approximately −6.1°C. More importantly, a statistical study revealed that the direct connection between fracture and nucleation of griseofulvin was weakened in the presence of PVP K90. This study also explored the effects of PVP K90 on the molecular dynamics and crystallization behaviors of amorphous GSF. In the presence of PVP K90, the crystal growth kinetics and molecular dynamics were both slowed down. Interestingly, needle‐like crystal growth was observed, exhibiting approximately the same rates as the bubble‐induced process. These findings are important for understanding the complex mechanisms of physical stability of polymer‐based amorphous solid dispersions. [ABSTRACT FROM AUTHOR]

The composition and technology for obtaining a solid dosed stable dosage form of a promising representative of the class of nitrogen monoxide (NO) donors, an anionic tetranitrosyl iron complex with thiosulfate ligands Na2[Fe2(S2O3)2(NO)4]·4H2O, were developed. The rate of NO generation by the complex could be modulated by using different types of excipients or by varying their concentrations. Albumin was found to be the optimal prolonging agent in the manufacture of this dosage form. The developed dosage form expanded the arsenal of long-acting NO-donor medicines used to treat socially significant diseases. [ABSTRACT FROM AUTHOR]

Background: Povidone, a synthetic polymer commonly used in various products such as antiseptics, cosmetics, and medications, has been associated with allergic reactions, including anaphylaxis. Despite its widespread use, cases of povidone-induced anaphylaxis, especially in children, are under-recognized. This case report aims to highlight the importance of considering povidone allergy in pediatric patients presenting with anaphylaxis. Case Presentation: We describe a 3-year-old boy who experienced anaphylaxis following the application of povidone–iodine antiseptic solution to a leg wound. He presented with generalized urticaria, angioedema, dyspnea, and cough. Prompt diagnosis and management were initiated in the emergency department. He experienced the second anaphylaxis with povidone-containing eye drops prescribed during an ophthalmology visit. Conclusions: Povidone allergy should be considered in pediatric patients presenting with anaphylaxis, especially those with idiopathic reactions or multiple drug allergies. Clinicians should emphasize patient education on label reading and the provision of adrenaline autoinjectors to prevent life-threatening reactions associated with povidone exposure. [ABSTRACT FROM AUTHOR]

PPMG-based composite electrolytes were fabricated via the solution method using the polyvinyl alcohol and polyvinylpyrrolidone blend reinforced with various contents of sulfonated inorganic filler. Sulfuric acid was employed as the sulfonating agent to functionalize the external surface of the inorganic filler, i.e., graphene oxide. The proton conductivities of the newly prepared proton exchange membranes (PEMs) were increased by increasing the temperature and content of sulfonated graphene oxide (SGO), i.e., ranging from 0.025 S/cm to 0.060 S/cm. The induction of the optimum level of SGO is determined to be an excellent route to enhance ionic conductivity. The single-cell performance test was conducted by sandwiching the newly prepared PEMs between an anode (0.2 mg/cm2 Pt/Ru) and a cathode (0.2 mg/cm2 Pt) to prepare membrane electrode assemblies, followed by hot pressing under a pressure of approximately 100 kg/cm2 at 60 °C for 5–10 min. The highest power densities achieved with PPMG PEMs were 14.9 and 35.60 mW/cm2 at 25 °C and 70 °C, respectively, at ambient pressure with 100% relative humidity. Results showed that the newly prepared PEMs exhibit good electrochemical performance. The results indicated that the prepared composite membrane with 6 wt% filler can be used as an alternative membrane for applications of high-performance proton exchange membrane fuel cell. [ABSTRACT FROM AUTHOR]

The work studied the influence of technological processes for producing hydrogels based on polyvinylpyrrolidone on their adhesive properties to metal implants made of medical NiTi with the aim of developing a medical product for prevention and treatment of periprosthetic infections. In the present study, the mechanisms of formation of hydrogels under various production conditions have been studied using ATR IR spectroscopy. Using the method of differential scanning calorimetry, changes in the phase transitions of polyvinylpyrrolidone (PVP) were studied in order to assess the adhesive properties of hydrogels, which was carried out by determining the contact angle of wetting. Based on the results of the study, mechanisms for cross linking of PVP have been proposed depending on the processing method. It has been revealed that the effect of high temperature on PVP leads to a slightly denser cross linking than the effect of γ irradiation; the values of the Mg index are within the same order of magnitude (Mg(PVP–TT) = 1.2 × 104, Mg(PVP–γ) = 1.0 × 104). Hydrogels wet metal surfaces made of medical NiTi well; their adhesive properties do not depend on differences in the production technologies. [ABSTRACT FROM AUTHOR]

In contrast to conventional chemical treatments, medicinal plants are more secure and efficient in treating wounds without the risk of adverse effects. Traditional wound dressings have no antibacterial features, and have an inadequate water vapour transmission rate (WVTR). Clove extracts (CE) were developed in this study to make the dressings more effective in humans. The morphological, physical, mechanical, biological, and antibacterial properties of CMC/PVP biocomposite films were explored with different clove extract (CE) concentrations (2 %, 4 %, and 6 %). Fourier transform infrared spectroscopy (FTIR) and X-ray diffraction (XRD) investigations demonstrated the structural relationships involving CMC, PVP, and CE in the reinforced samples. The TGA results validate the CMC/PVP/CE bio-composite hydrogel’s potential for usage in medicinal applications. The developed bio-composite hydrogels showed > 87 % cell viability against Vero cells, were favourable to cell growth, and had a significant zone of inhibition against S. aureus and E. coli bacteria. CMC/PVP/CE (6 %) bio-composite hydrogel enhanced wound healing in albino mice within 12 days, had a WVTR of 2310 g/m2-day and an ESR% of 1712 %. In addition, the results of the histological examination corroborated the observations of faster tissue regeneration, less inflammatory cells, and enhanced vascularity of the surrounding skin. The overall results encourage and show that CMC/PVP/CE (6 %) bio-composite hydrogels have a lot of potential uses in the biomedical field, especially for wound healing.

In this study, core-shell nanofibers were produced by using hydrophilic polyvinylpyrrolidone (PVP) polymer in the core and hydrophobic poly(e-caprolactone) (PCL) polymer in the shell. Essential oil added nanofiber structures were developed by adding thyme oil (TEO) and borage oil (BO) in the PVP core part by using Triton X 100 (TX-100) as the surfactant. 8% PVP-8% PCL nanofibers were produced by adding TEO, BO and a 1:1 volume/volume mixture of these two (TEO:BO) to the PVP solution. Addition of essential oil and surfactant to the solutions resulted in different conductivity and viscosity values. SEM images were analyzed and it was observed that nanofiber diameters increased when essential oil and surfactant were added to the core of the coaxial nanofibers. Pristine, TEO added, TEO:BO added and BOadded nanofibers were calculated as 145 ± 66, 233 ± 150, 245 ± 165 and 300 ± 124 nm, respectively. Besides, water contact angle measurements showed that TX-100 and essential oil additives caused high hydrophilization of nanofiber by changing the hydrophobic nature of PCL. While the contact angle of the 8% PVP-8% PCL sample without additives were 98°, the contact angle of the oil and surfactant containing samples were measured as 0°. In conclusion, it was observed that the nanofiber morphology and surface properties changed when different essential oils and surfactant were added to the core-shell nanofibers.

The purpose of the research is to analyze the dynamics of fenbendazole (FBZ) and niclozamide (NZM) release from their solid dispersions (SD) of various compositions by dialysis through various semipermeable membranes in model systems that correspond to stomach and intestine environments. To evaluate the parasitocidal activity of experimental mixture compositions.Materials and methods. The study used substances of FBZ and NZM, and the polymer, polyvinylpyrrolidone (PVP). Mechanical processes were carried out in a LE-101 roller mill and an AGO-2 orbital centrifugal mill at different power density levels. The resulting SD of various compositions were studied for solubility. The dynamics of FBZ and NZM substance release from the SD were studied in a laboratory setup consisting of a temperature controlled glass with buffer solutions with pH = 9.18 (intestinal environment) and pH = 1.0 (stomach environment). The substance concentration in the dialysate was determined by HPLC and UV spectroscopy. The resulting complex SD of FBZ and NZM were studied for cestodocidal activity in a laboratory model of hymenolepiosis of white mice.Results and discussion. It was found that the substances release into a buffer solution with pH = 9.18 from the SD obtained in the roller mill is higher than that of the SD obtained in the AGO activator. The dialysis of the experimental compounds in a model system with a gastric juice medium observed only FBZ substance penetration through the membrane, which can be explained by protonation of the FBZ molecule which is a weak base. The NZM molecule, being a neutral molecule, does not penetrate through the semi-permeable partition into the hydrochloric acid environment; it remains entirely inside the dialysis bag. High anthelmintic efficacy rates (up to 100%) of SD complex FBZ : NZM : PVP obtained in the AGO activator and in the roller mill were recorded for the SD of composition 2 : 20 : 78 in the mice with hymenolepiosis. The activity of the base drug, the niclozamide substance, was 27.69%, which is 3 times lower than the activity of the resulting complex dispersions.