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1.
Folia Med (Plovdiv) ; 66(3): 356-360, 2024 Jun 30.
Artículo en Inglés | MEDLINE | ID: mdl-39365634

RESUMEN

INTRODUCTION: Surgical repair of the anterior abdominal wall hernia is the most common intervention in general surgery practice. The introduction of synthetic prostheses reduces the frequency of recurrences, but in many cases, they are associated with complications that could seriously impair the quality of life of patients. To reduce perioperative complications, we introduced in our practice innovative prostheses made of a highly inert polymer, polyvinylidene fluoride (PVDF), and conducted an observational study.


Asunto(s)
Polivinilos , Humanos , Femenino , Masculino , Persona de Mediana Edad , Herniorrafia/métodos , Anciano , Mallas Quirúrgicas , Hernia Ventral/cirugía , Complicaciones Posoperatorias/prevención & control , Hernia Abdominal/cirugía , Polímeros de Fluorocarbono
2.
Biosensors (Basel) ; 14(9)2024 Aug 24.
Artículo en Inglés | MEDLINE | ID: mdl-39329786

RESUMEN

Current ammonia sensors exhibit cross-sensitivity to water vapor, leading to false alarms. We developed a core-shell nanofiber (CSNF) structure to address these issues, using conductive poly(3,4-ethylenedioxythiophene) (PEDOT) as the core and hydrophobic polyvinylidene fluoride-tetrafluoroethylene (PVDF-TrFE) as the shell. The PEDOT-PVDF CSNF, with a diameter of ~500 nm and a 300 nm thick PVDF layer, showed a superior sensitivity and humidity resistance compared to conventional PEDOT membranes for ammonia concentrations of 10-100 ppm. In humid environments, CSNF sensors outperformed membrane sensors, exhibiting a tenfold increase in performance at 51% relative humidity (RH). This study highlights the potential of CSNF sensors for practical ammonia detection, maintaining a high performance under varying humidity levels.


Asunto(s)
Amoníaco , Compuestos Bicíclicos Heterocíclicos con Puentes , Humedad , Nanofibras , Polímeros , Polivinilos , Amoníaco/análisis , Compuestos Bicíclicos Heterocíclicos con Puentes/química , Polímeros/química , Polivinilos/química , Técnicas Biosensibles , Polímeros de Fluorocarbono
3.
Biomed Mater ; 19(6)2024 Sep 30.
Artículo en Inglés | MEDLINE | ID: mdl-39303743

RESUMEN

Adequate simulation mimicking a tissue's native environment is one of the elemental premises in tissue engineering. Although various attempts have been made to induce human mesenchymal stem cells (hMSC) into an osteogenic pathway, they are still far from widespread clinical application. Most strategies focus primarily on providing a specific type of cue, inadequately replicating the complexity of the bone microenvironment. An alternative multifunctional platform for hMSC osteogenic differentiation has been produced. It is based on poly(vinylidene fluoride) (PVDF) and cobalt ferrites magnetoelectric microspheres, functionalized with collagen and gelatin, and packed in a 3D arrangement. This platform is capable of performing mechanical stimulation of piezoelectric PVDF, mimicking the bones electromechanical biophysical cues. Surface functionalization with extracellular matrix biomolecules and osteogenic medium complete this all-round approach. hMSC were cultured in osteogenic inducing conditions and tested for proliferation, surface biomarkers, and gene expression to evaluate their osteogenic commitment.


Asunto(s)
Diferenciación Celular , Proliferación Celular , Células Madre Mesenquimatosas , Osteogénesis , Polivinilos , Ingeniería de Tejidos , Humanos , Células Madre Mesenquimatosas/citología , Ingeniería de Tejidos/métodos , Polivinilos/química , Células Cultivadas , Andamios del Tejido/química , Materiales Biomiméticos/química , Gelatina/química , Biomimética , Matriz Extracelular/metabolismo , Colágeno/química , Microesferas , Cobalto/química , Cobalto/farmacología , Microambiente Celular , Polímeros de Fluorocarbono
4.
J Mater Chem B ; 12(38): 9727-9739, 2024 Oct 02.
Artículo en Inglés | MEDLINE | ID: mdl-39224031

RESUMEN

High-performance biocompatible composite materials are gaining attention for their potential in various fields such as neural tissue scaffolds, bio-implantable devices, energy harvesting, and biomechanical sensors. However, these devices currently face limitations in miniaturization, finite battery lifetimes, fabrication complexity, and rigidity. Hence, there is an urgent need for smart and self-powering soft devices that are easily deployable under physiological conditions. Herein, we present a straightforward and efficient fabrication technique for creating flexible/stretchable fiber-based piezoelectric structures using a hybrid nanocomposite of polyvinylidene fluoride (PVDF), reduced graphene oxide (rGO), and barium-titanium oxide (BT). These nanocomposite fibers are capable of converting biomechanical stimuli into electrical signals across various structural designs (knit, braid, woven, and coil). It was found that a stretchable configuration with higher output voltage (4 V) and a power density (87 µW cm-3) was obtained using nanocomposite coiled fibers or knitted fibers, which are ideal candidates for real-time monitoring of physiological signals. These structures are being proposed for practical transition to the development of the next generation of fiber-based biomedical devices. The cytotoxicity and cytocompatibility of nanocomposite fibers were tested on human mesenchymal stromal cells. The obtained results suggest that the developed fibers can be utilized for smart scaffolds and bio-implantable devices.


Asunto(s)
Grafito , Nanocompuestos , Polivinilos , Titanio , Nanocompuestos/química , Grafito/química , Titanio/química , Polivinilos/química , Humanos , Materiales Biocompatibles/química , Materiales Biocompatibles/farmacología , Compuestos de Bario/química , Células Madre Mesenquimatosas/efectos de los fármacos , Células Madre Mesenquimatosas/citología , Polímeros de Fluorocarbono
5.
Chem Res Toxicol ; 37(9): 1588-1597, 2024 Sep 16.
Artículo en Inglés | MEDLINE | ID: mdl-39237351

RESUMEN

Histones and their posttranslational modifications (PTMs) are critical regulators of gene expression. Differentiation, environmental stressors, xenobiotics, and major human diseases cause significant changes in histone variants and PTMs. Western blotting is the mainstay methodology for detection of histones and their PTMs in the majority of studies. Surprisingly, despite their high abundance in cells, immunoblotting of histones typically involves loading of large protein amounts that are normally used for detection of sparse cellular proteins. We systematically examined technical factors in the Western-blotting-based detection of human histones with >30 antibodies. We found that under multiple protein transfer conditions, many histone epitopes on polyvinylidene fluoride (PVDF) membranes had a very low antibody accessibility, which was dramatically increased by the addition of a simple denaturation step. Denaturation of membrane-bound proteins also enhanced the specificity of some histone antibodies. In comparison to standard PVDF membranes, the sensitivity of histone detection on standard nitrocellulose membranes was typically much higher, which was further increased by the inclusion of the same denaturation step. Optimized protocols increased by >100-times detection sensitivity for the genotoxic marker γ-H2AX with two monoclonal antibodies. The impact of denaturation and nitrocellulose use varied for different histones, but for each histone, it was generally similar for antibodies targeting N-terminal and C-terminal regions. In summary, denaturation of membrane-bound histones strongly improves their detection by Westerns, resulting in more accurate measurements and permitting analyses with small biological samples.


Asunto(s)
Histonas , Histonas/química , Histonas/metabolismo , Histonas/análisis , Humanos , Western Blotting , Polivinilos/química , Polímeros de Fluorocarbono
6.
Chemosphere ; 365: 143403, 2024 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-39321883

RESUMEN

The goal of this study was to provide data to support mineralization of fluoropolymer waste and insignificant generation of PFAS as products of incomplete combustion (PIC) during incineration of fluoropolymer applications at their end-of-life. Destruction efficiency is not an acceptable metric to indicate mineralization and therefore we need to look for and measure products of incomplete destruction. A mixed sample of fluoropolymers representing 80% of commercial fluoropolymers was combusted at conditions representative of municipal and industrial waste incinerators operating in EU. State-of-the-art emission sampling and analytical methods (UPLC-MS/MS, GC-MS) were used for identifying and quantifying those PFAS whose standards were available. Statistical analysis of the results confirmed non-detect to negligible levels of PFAS evidencing mineralization of fluoropolymers.


Asunto(s)
Residuos Peligrosos , Incineración , Residuos Peligrosos/análisis , Polímeros de Fluorocarbono/química , Cromatografía de Gases y Espectrometría de Masas , Europa (Continente) , Espectrometría de Masas en Tándem , Contaminantes Atmosféricos/análisis , Proyectos Piloto
7.
Biomater Sci ; 12(20): 5164-5185, 2024 Oct 08.
Artículo en Inglés | MEDLINE | ID: mdl-39258881

RESUMEN

In recent years, poly(vinylidene fluoride) (PVDF) has emerged as a versatile polymer with a wide range of applications across various fields. PVDF's piezosensitivity, versatility, crystalline structure, and tunable parameters have established it as a highly sought-after material. Furthermore, PVDF and its copolymers exhibit excellent processability and chemical resistance to a diverse array of substances. Of particular significance is its remarkable structural stability in physiological media, which highlights its potential for use in the development of biomedical products. This review offers a comprehensive overview of the latest advancements in PVDF-based biomedical systems. It examines the fabrication of stimulus-responsive delivery systems, bioelectric therapy devices, and tissue-regenerating scaffolds, all of which harness the piezosensitivity of PVDF. Moreover, the potential of PVDF in the fabrication of both invasive and non-invasive diagnostic tools is investigated, with particular emphasis on its flexibility, transparency, and piezoelectric efficiency. The material's high biocompatibility and physiological stability are of paramount importance in the development of implantable sensors for long-term health monitoring, which is crucial for the management of chronic diseases and postoperative care. Additionally, we discuss a novel approach to photoacoustic microscopy that employs a PVDF sensor, thereby eliminating the necessity for external contrast agents. This technique provides a new avenue for non-invasive imaging in biomedical applications. Finally, we explore the challenges and prospects for the development of PVDF-based systems for a range of biomedical applications. This review is distinctive in comparison to other reviews on PVDF due to its concentrated examination of biomedical applications, including pioneering imaging techniques, long-term health monitoring, and a detailed account of advancements in the field. Collectively, these elements illustrate the potential of PVDF to markedly influence biomedical engineering and patient care, distinguishing it from existing literature. By leveraging the distinctive attributes of PVDF and its copolymers, researchers can continue to advance the frontiers of biomedical engineering, with the potential to transform patient care and treatment outcomes.


Asunto(s)
Polivinilos , Humanos , Polivinilos/química , Materiales Biocompatibles/química , Animales , Polímeros/química , Polímeros de Fluorocarbono
8.
Waste Manag ; 188: 60-71, 2024 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-39116657

RESUMEN

The effective recovery of valuables from anodes coming from spent lithium-ion batteries (LIBs) is of great importance to ensure resource supply and reduce the environmental burden for recycling. In this work, a simple and low energy consumption roasting method was proposed by employing low-temperature eutectic NaOH-KOH as reaction medium, in order to simultaneously separate graphite from Cu foils, extract lithium from it and set it up for reuse as environmental catalyst through one-step water washing process. Our results show that polyvinylidene difluoride (PVDF) was effectively deactivated due to dehydrofluorination/carbonization at a relatively low temperature and short time (150 °C, 20 min) when a mass ratio of 1:1 for eutectic NaOH-KOH to spent LIBs anodes was used, yielding 97.3 % of graphite detached. Moreover, a remarkable lithium extraction efficiency of 93.2 % was simultaneously obtained. Afterwards, the reusability of the recycled graphite was tested by employing it as a catalyst for the treatment of a contaminant organic dye (Rhodamine B) in the presence of NaClO. Our results show that a superior NaClO activation was obtained with the addition of recycled graphite, being this fact closely associated to the abundant active sites formed during the long-term charging/discharging cycles in the original battery. The alkaline-mediated roasting process presented in this work presents an energy-saving scheme to efficiently recover useful components from spent anodes, whereas the reusability example highlighted a useful option for repurposing the severely damaged graphite as an environmental catalyst rather than disposing it in landfills, turning waste into a valuable material.


Asunto(s)
Suministros de Energía Eléctrica , Electrodos , Grafito , Litio , Reciclaje , Reciclaje/métodos , Grafito/química , Catálisis , Residuos Electrónicos , Polivinilos/química , Polímeros de Fluorocarbono
9.
Biomacromolecules ; 25(9): 5541-5591, 2024 Sep 09.
Artículo en Inglés | MEDLINE | ID: mdl-39129463

RESUMEN

The future development of wearable/implantable sensing and medical devices relies on substrates with excellent flexibility, stability, biocompatibility, and self-powered capabilities. Enhancing the energy efficiency and convenience is crucial, and converting external mechanical energy into electrical energy is a promising strategy for long-term advancement. Poly(vinylidene fluoride) (PVDF), known for its piezoelectricity, is an outstanding representative of an electroactive polymer. Ingeniously designed PVDF-based polymers have been fabricated as piezoelectric devices for various applications. Notably, the piezoelectric performance of PVDF-based platforms is determined by their structural characteristics at different scales. This Review highlights how researchers can strategically engineer structures on microscopic, mesoscopic, and macroscopic scales. We discuss advanced research on PVDF-based piezoelectric platforms with diverse structural designs in biomedical sensing, disease diagnosis, and treatment. Ultimately, we try to give perspectives for future development trends of PVDF-based piezoelectric platforms in biomedicine, providing valuable insights for further research.


Asunto(s)
Polivinilos , Polivinilos/química , Humanos , Materiales Biocompatibles/química , Polímeros de Fluorocarbono
10.
Water Res ; 263: 122176, 2024 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-39128422

RESUMEN

Membrane distillation (MD) presents a promising alternative to conventional desalination systems, particularly for the treatment of hypersaline wastewater. However, the large-scale application of MD is hindered by challenges such as membrane wetting, membrane fouling, and low permeate flux. Herein, we proposed an air/liquid interface deposition method to fabricate a Janus membrane, termed the PVDF-PDA/PEI-Si membrane. The membrane featured a nanosieving, superhydrophilic polydopamine/polyethylenimine (PDA/PEI) layer decorated with silica nanoparticles, coupled with a microporous, hydrophobic polyvinylidene fluoride (PVDF) layer. The introduction of a dense PDA/PEI-Si layer featuring high surface energy significantly enhanced the wetting and fouling resistance of the membrane, with a minor effect on the permeate flux. The performance enhancement was particularly evident when hypersaline water containing sodium dodecyl sulfate (SDS) and oily contaminants was used as the feed. The interactions between the membrane and contaminants were calculated using the XDLVO theory and molecular dynamics simulations to elucidate the mechanisms underlying the enhanced anti-wetting and anti-fouling properties, respectively. According to the XDLVO theory, a large energy barrier must be overcome for the SDS to attach onto the PDA/PEI-Si surface. Meanwhile, molecular dynamics simulations confirmed the weak interaction energy between the oily foulants and the PVDF-PDA/PEI-Si membrane due to its high surface energy. This study presents a promising approach for the fabrication of high-performance MD membranes and provides new insights into the mechanisms underlying the enhanced anti-wetting and anti-fouling properties.


Asunto(s)
Destilación , Membranas Artificiales , Destilación/métodos , Purificación del Agua/métodos , Humectabilidad , Polivinilos/química , Interacciones Hidrofóbicas e Hidrofílicas , Incrustaciones Biológicas/prevención & control , Indoles/química , Polímeros/química , Polímeros de Fluorocarbono
11.
Mikrochim Acta ; 191(9): 526, 2024 08 09.
Artículo en Inglés | MEDLINE | ID: mdl-39120744

RESUMEN

A LOx-based electrochemical biosensor for high-level lactate determination was developed. For the construction of the biosensor, chitosan and Nafion layers were integrated by using a spin coating procedure, leading to less porous surfaces in comparison with those recorded after a drop casting procedure. The analytical performance of the resulting biosensor for lactate determination was evaluated in batch and flow regime, displaying satisfactory results in both modes ranging from 0.5 to 20 mM concentration range for assessing the lactic acidosis. Finally, the lactate levels in raw serum samples were estimated using the biosensor developed and verified with a blood gas analyzer. Based on these results, the biosensor developed is promising for its use in healthcare environment, after its proper miniaturization. A pH probe based on common polyaniline-based electrochemical sensor was also developed to assist the biosensor for the lactic acidosis monitoring, leading to excellent results in stock solutions ranging from 6.0 to 8.0 mM and raw plasma samples. The results were confirmed by using two different approaches, blood gas analyzer and pH-meter. Consequently, the lactic acidosis monitoring could be achieved in continuous flow regime using both (bio)sensors.


Asunto(s)
Técnicas Biosensibles , Técnicas Electroquímicas , Ácido Láctico , Técnicas Biosensibles/métodos , Técnicas Biosensibles/instrumentación , Concentración de Iones de Hidrógeno , Ácido Láctico/sangre , Técnicas Electroquímicas/métodos , Técnicas Electroquímicas/instrumentación , Humanos , Acidosis Láctica/sangre , Acidosis Láctica/diagnóstico , Quitosano/química , Polímeros de Fluorocarbono/química , Compuestos de Anilina/química , Enzimas Inmovilizadas/química , Oxigenasas de Función Mixta
12.
PLoS One ; 19(8): e0308026, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39088569

RESUMEN

Electrospinning is a process in which high voltage creates nanostructured fibers with random orientation from a polymer solution. A novel electrospinning instrument was designed and constructed, capable of orienting and collimating the trajectory of the electrified fluid jet. The equipment collimates and adjusts the electrified fluid jet in the X-Y directions using deflector plates connected to a variable electric field. Simultaneously, different membrane thicknesses can be selected, i.e., in the Z direction. Additionally, by programming the sinusoidal function generator to perform an X-Y sweep, Lissajous figures (LF) were obtained. SEM images obtained through XYZ electrospinning of PVC and PVDF membranes were used to determine the control achieved over the orientation distribution of the processed nanofibers and the modification of their diameter, with and without applying the electric field to the deflector plates. The nanofibers obtained from the polymeric membranes, which originated after the straight segment of the Taylor cone, did not exhibit a random trajectory and position. Instead, the collimated electrified fluid jet deposited them in a cross pattern (X-Y) on the collector-cathode plate.


Asunto(s)
Electricidad , Nanofibras , Polímeros , Nanofibras/química , Polímeros/química , Cloruro de Polivinilo/química , Polivinilos/química , Polímeros de Fluorocarbono
13.
Sci Rep ; 14(1): 18560, 2024 08 09.
Artículo en Inglés | MEDLINE | ID: mdl-39122869

RESUMEN

The treatment of parastomal hernias (PSH) represents a major challenge in hernia surgery. Various techniques have been reported with different outcomes in terms of complication and recurrence rates. The aim of this study is to share our initial experience with the implantation of the DynaMesh-IPST-R and -IPST, intraperitoneal funnel meshes made of polyvinylidene fluoride (PVDF). This is a retrospective observational cohort study of patients treated for PSH between March 2019 and April 2023 using the chimney technique with the intraperitoneal funnel meshes IPST-R or IPST. The primary outcome was recurrence and the secondary outcomes were intraoperative and postoperative complications, the latter assessed using the Clavien-Dindo classification. A total of 21 consecutive patients were treated with intraperitoneal PVDF funnel meshes, 17 with IPST-R and 4 with IPST. There were no intraoperative complications. Overall, no complications occurred in 61.9% (n = 12) of the patients. Major postoperative complications (defined as Clavien-Dindo ≥ 3b) were noted in four cases (19.0%). During the mean follow-up period of 21.6 (range 4.8-37.5) months, one patient (4.8%) had a recurrence. In conclusion, for the treatment of parastomal hernias, the implantation of IPST-R or IPST mesh has proven to be efficient, easy to handle, and very safe. In particular, the low recurrence rate of 4.8%, which is in line with the current literature, is convincing. However, a larger number of patients would improve the validity of the results.


Asunto(s)
Herniorrafia , Complicaciones Posoperatorias , Mallas Quirúrgicas , Humanos , Mallas Quirúrgicas/efectos adversos , Masculino , Femenino , Persona de Mediana Edad , Anciano , Estudios Retrospectivos , Herniorrafia/métodos , Herniorrafia/efectos adversos , Herniorrafia/instrumentación , Complicaciones Posoperatorias/etiología , Resultado del Tratamiento , Polivinilos , Adulto , Recurrencia , Anciano de 80 o más Años , Hernia Incisional/cirugía , Hernia Incisional/etiología , Hernia Ventral/cirugía , Hernia Ventral/etiología , Polímeros de Fluorocarbono
14.
Int J Food Microbiol ; 425: 110870, 2024 Dec 02.
Artículo en Inglés | MEDLINE | ID: mdl-39151230

RESUMEN

Food contaminated by pathogenic bacteria poses a serious threat to human health. Consequently, we used Salmonella as a model and developed an electrochemical immunosensor based on a polydopamine/CoFe-MOFs@Nafion nanocomposite for the detection of Salmonella in milk. The CoFe-MOFs exhibit good stability, large specific surface area, and high porosity. However, after modification on the electrode surface, they were prone to detachment. This issue was effectively mitigated by incorporating Nafion into the nanocomposite. A polydopamine (PDA) film was deposited onto the surface of CoFe-MOFs@Nafion through cyclic voltammetry (CV), accompanied by an investigation into the polymerization mechanism of the PDA film. PDA contains a substantial number of quinone functional groups, which can covalently bind to amino or sulfhydryl groups via Michael addition reaction or Schiff base reaction, thereby immobilizing anti-Salmonella antibodies onto the modified electrode surface. Under the optimal experimental conditions, the Salmonella concentration exhibited a good linear relationship within the range of 1.38 × 102 to 1.38 × 108 CFU mL-1, with a detection limit of 1.38 × 102 CFU mL-1. Furthermore, the constructed immunosensor demonstrated good specificity, stability, and reproducibility, offering a novel approach for the rapid detection of foodborne pathogens.


Asunto(s)
Técnicas Biosensibles , Técnicas Electroquímicas , Electrodos , Polímeros de Fluorocarbono , Oro , Indoles , Leche , Polímeros , Salmonella , Polímeros/química , Salmonella/aislamiento & purificación , Leche/microbiología , Polímeros de Fluorocarbono/química , Animales , Oro/química , Técnicas Electroquímicas/métodos , Técnicas Biosensibles/métodos , Contaminación de Alimentos/análisis , Límite de Detección , Microbiología de Alimentos , Estructuras Metalorgánicas/química , Inmunoensayo/métodos , Reproducibilidad de los Resultados , Nanocompuestos/química
15.
Chemosphere ; 364: 143094, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-39151589

RESUMEN

Organic pollutants, such as toluene and xylene, in industrial wastewater negatively impact the environment. Membrane treatment is one of the best methods to reduce impurities in wastewater. Existing membranes that coat the water surface with hydrophilic material only effectively resist the initial fouling, resulting in poor oil and water selectivity. Here we report a simple and efficient method to enhance the water flux and antifouling properties of polyvinylidene fluoride (PVDF) membranes. This method involves developing and applying Catechol-Fe(III) complexes with a rough surface to the PVDF surface. Forming Catechol-Fe(III) complexes on the surface better anchors them to the membrane than the dip-coating method. The PVDF membranes with rough Catechol-Fe(III) complexes are superoleophobic, with an oil contact angle of 152 ° and high permeability, with pure water flux of 10487 Lm-2h-1bar-1 and 1 wt% toluene in water emulsion flux of 4697 Lm-2h-1bar-1. Overall, the straightforward manufacturing process, increased permeability, and outstanding antifouling capabilities of the PVDF membrane incorporating rough nanoparticles offer promising prospects for designing and implementing suitable membranes for oil in water emulsion separation applications.


Asunto(s)
Catecoles , Membranas Artificiales , Polivinilos , Contaminantes Químicos del Agua , Catecoles/química , Polivinilos/química , Contaminantes Químicos del Agua/química , Aguas Residuales/química , Interacciones Hidrofóbicas e Hidrofílicas , Compuestos Férricos/química , Incrustaciones Biológicas/prevención & control , Permeabilidad , Tolueno/química , Purificación del Agua/métodos , Polímeros de Fluorocarbono
16.
Chemosphere ; 364: 143169, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-39181459

RESUMEN

In this work, polyvinylidene fluoride (PVDF) intercalated CuFe layered double hydroxides (LDH) membranes were fabricated and investigated for UV-LED/persulfate degradation of methylene blue (MB), crystal violet (CV), methyl orange (MO), and Eriochrome black T (EBT) dyes from water. The PVDF-CuFe membrane exhibited improved heterogeneity, surface functionality (CuO, Fe-O, Cu-O-Fe), surface roughness, and hydrophilicity. The process parameters were optimized by response surface methodology, and maximum MB removal (100%) was achieved within 45.22-178.5 min at MB concentration (29.45-101.93 mg/L), PP concentration (0.5-2.41 g/L) and catalyst dosage (1.84-1.95 g/L). The degradation kinetics was well described by a pseudo-first-order model (R2 = 0.982) and fast reaction rate (0.029-0.089/min). The MB dye degradation mechanism is associated with HO·/SO4•- reactive species generated by Fe3+/Fe2+ or Cu2+/Cu+ in PVDF-CuFe membrane and PP dissociation. The PVDF-CuFe membrane demonstrated excellent recyclability performance with a 12% reduction after five consecutive cycles. The catalytic membrane showed excellent photocatalytic degradation of crystal violet (100%), methyl orange (79%), and Eriochrome black T (60%). The results showed that UV-LED/persulfate-assisted PVDF-CuFe membranes can be used as a recyclable catalyst for the effective degradation of dye-contaminated water streams.


Asunto(s)
Compuestos Azo , Colorantes , Hidróxidos , Azul de Metileno , Polivinilos , Contaminantes Químicos del Agua , Colorantes/química , Contaminantes Químicos del Agua/química , Hidróxidos/química , Compuestos Azo/química , Catálisis , Azul de Metileno/química , Polivinilos/química , Violeta de Genciana/química , Cinética , Purificación del Agua/métodos , Cobre/química , Restauración y Remediación Ambiental/métodos , Polímeros de Fluorocarbono
17.
Environ Sci Pollut Res Int ; 31(40): 53424-53436, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-39190248

RESUMEN

This work is primarily focused on overcoming the limitations of polymeric membranes in achieving the balance between permeability and selectivity of the separation performance. The filler, Zeolitic imidazole framework -67 (ZIF-67) nanoparticles were synthesised in cubical morphology using hexadecyltrimethylammonium bromide (CTAB) as a surfactant via the wet-chemical method. The uniform particles with particle sizes ranging between 120-180 nm were incorporated into the polyvinylidene fluoride (PVDF) matrix to fabricate mixed matrix membranes via the phase inversion method. These mixed matrix membranes were systematically characterised to confirm the chemical, structural and morphological properties of the materials and membranes. Furthermore, the membranes showed a 56.5% improvement in their mechanical properties. The results confirm that 5 wt.% ZIF-67/PVDF membrane showed the best separation results compared to its pure counterpart. The permeability of H2 gas was reported to be 1,094,511 Barrer, with selectivities of 3.03 for H2/CO2 and 3.06 for H2/N2. This represents a 210.6% increase in the permeability of H2 gas. These results demonstrate the influence of ZIF-67 loading in the PVDF polymer matrix along with the potential of ZIF-67/PVDF mixed matrix membranes in the field of hydrogen separation and purification.


Asunto(s)
Hidrógeno , Membranas Artificiales , Polivinilos , Zeolitas , Polivinilos/química , Zeolitas/química , Hidrógeno/química , Permeabilidad , Polímeros/química , Imidazoles/química , Polímeros de Fluorocarbono
18.
Colloids Surf B Biointerfaces ; 243: 114123, 2024 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-39079183

RESUMEN

Implant failure is primarily caused by poor osseointegration and bacterial colonization, which demands readmissions and revision surgeries to correct it. A novel approach involves engineering multifunctional interfaces using piezoelectric polyvinylidene fluoride (PVDF) materials, which mimic bone tissue's electroactive properties to promote bone integration and provide antibacterial functionality when mechanically stimulated. In this study, PVDF films were coated with antibacterial essential oil nanoparticles and antibiofilm enzymes using a layer-by-layer (LBL) approach to ensure antibacterial properties even without mechanical stimulation. The experimental results confirmed the LBL build-up and demonstrated notable antibiofilm properties against Pseudomonas aeruginosa and Staphylococcus aureus while enhancing pre-osteoblast cell proliferation under mechanical dynamic conditions in a bioreactor that replicated the real-life environment of implants within the body. The findings highlight the potential of PVDF-coated surfaces to prevent biofilm formation and boost cell proliferation through the piezoelectric effect, paving the way for advanced implantable devices with improved osseointegration and antibacterial performance.


Asunto(s)
Antibacterianos , Biopelículas , Proliferación Celular , Materiales Biocompatibles Revestidos , Oseointegración , Polivinilos , Pseudomonas aeruginosa , Staphylococcus aureus , Propiedades de Superficie , Antibacterianos/farmacología , Antibacterianos/química , Oseointegración/efectos de los fármacos , Pseudomonas aeruginosa/efectos de los fármacos , Pseudomonas aeruginosa/fisiología , Staphylococcus aureus/efectos de los fármacos , Staphylococcus aureus/fisiología , Biopelículas/efectos de los fármacos , Proliferación Celular/efectos de los fármacos , Materiales Biocompatibles Revestidos/química , Materiales Biocompatibles Revestidos/farmacología , Polivinilos/química , Polivinilos/farmacología , Animales , Ratones , Pruebas de Sensibilidad Microbiana , Osteoblastos/efectos de los fármacos , Osteoblastos/citología , Polímeros de Fluorocarbono
19.
Talanta ; 279: 126558, 2024 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-39047630

RESUMEN

Although membrane technology has demonstrated outstanding pathogen removal capabilities, current commercial membranes are insufficient for removing small viruses at trace levels due to certain limitations. The theoretical and practical significance of developing a new form of hydrophilic, anti-fouling, and virus-specific ultra-purification membrane with high capturing and separation efficiency, stability, and throughput for water treatment is of the utmost importance. In this study, molecularly imprinted membranes (MIMs) were fabricated from polyvinylidene fluoride (PVDF) membranes utilizing novel surface hydrophilic modification techniques, followed by the immobilization of virus-specific molecularly imprinted nanoparticles (nanoMIPs) as synthetic receptors. Three distinct membrane functionalization strategies were established and optimized for the first time: membrane functionalization with (i) polyethyleneimine (PEI) and dopamine (DOP), (ii) PEI and 3-(chloropropyl)-trimethoxysilane (CTS), and (iii) chitosan (CS). Hydrophilicity was enhanced significantly as a result of these modification strategies. Additionally, the modifications enabled spacer arms between the membrane surface and the nanoMIPs to decrease steric hindrance. The surface chemistry, morphology, and membrane performance results from the characterization analysis of the MIMs demonstrated excellent hydrophilicity (e.g., the functionalized membrane presented 37.84° while the unmodified bare membrane exhibited 128.94° of water contact angle), higher permeation flux (145.96 L m-2 h-1 for the functionalized membrane), excellent uptake capacity (up to 99.99 % for PEI-DOP-MIM and CS-MIM), and recovery (more than 80 % for PEI-DOP-MIM). As proof of concept, the cutting-edge MIMs were able to eliminate the model adenoviruses up to 99.99 % from water. The findings indicate that the novel functionalized PVDF membranes hold promise for implementation in practical applications for virus capture and separation.


Asunto(s)
Membranas Artificiales , Polivinilos , Propiedades de Superficie , Ultrafiltración , Polivinilos/química , Ultrafiltración/métodos , Interacciones Hidrofóbicas e Hidrofílicas , Virus/aislamiento & purificación , Impresión Molecular/métodos , Polietileneimina/química , Purificación del Agua/métodos , Nanopartículas/química , Polímeros de Fluorocarbono
20.
Chemosphere ; 363: 142808, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-38992443

RESUMEN

The design of hydrophilic polyvinylidene fluoride (PVDF) membranes with anti-fouling properties has been explored for decades. Surface modification and blending are typical strategies to tailor the hydrophilicity of PVDF membranes. Herein, cyclodextrin was used to improve the antifouling performance of PVDF membranes. Cyclodextrin-modified PVDF membranes were prepared by coupling PVDF amination (blending with branched polyethyleneimine) and activated cyclodextrin grafting. The blending of PEI in the PVDF casting solution preliminarily aminated the PVDF, resulting in PEI-crosslinked/grafted PVDF membranes after phase inversion. Aldehydes groups on cyclodextrin, introduced by oxidation, endow cyclodextrin to be grafted on the aminated PVDF membrane by the formation of imines. Borch reduction performed on the activated cyclodextrin-grafted PVDF membrane converted the imine bonds to secondary amines, ensuring the membrane stability. The resulting membranes possess excellent antifouling performance, with a lower protein adsorption capacity (5.7 µg/cm2, indicated by Bovine Serum Albumin (BSA)), and a higher water flux recovery rate (FRR = 96%). The proposed method provides a facial strategy to prepare anti-fouling PVDF membranes.


Asunto(s)
Incrustaciones Biológicas , Ciclodextrinas , Interacciones Hidrofóbicas e Hidrofílicas , Membranas Artificiales , Polivinilos , Polivinilos/química , Incrustaciones Biológicas/prevención & control , Ciclodextrinas/química , Adsorción , Albúmina Sérica Bovina/química , Polímeros de Fluorocarbono
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