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The secreted phospholipase A2 (sPLA2) isoform, sPLA2-IIA, has been implicated in a variety of diseases and conditions, including bacteremia, cardiovascular disease, COVID-19, sepsis, adult respiratory distress syndrome, and certain cancers. Given its significant role in these conditions, understanding the regulatory mechanisms impacting its levels is crucial. Genome-wide association studies (GWAS) have identified several single nucleotide polymorphisms (SNPs), including rs11573156, that are associated with circulating levels of sPLA2-IIA. The work in the manuscript leveraged 4 publicly available datasets to investigate the mechanism by which rs11573156 influences sPLA2-IIA levels via bioinformatics and modeling analysis. Through genotype-tissue expression (GTEx), 234 expression quantitative trait loci (eQTLs) were identified for the gene that encodes for sPLA2-IIA, PLA2G2A. SNP2TFBS was used to ascertain the binding affinities between transcription factors (TFs) to both the reference and alternative alleles of identified eQTL SNPs. Subsequently, candidate TF-SNP interactions were cross-referenced with the ChIP-seq results in matched tissues from ENCODE. SP1-rs11573156 emerged as the significant TF-SNP pair in the liver. Further analysis revealed that the upregulation of PLA2G2A transcript levels through the rs11573156 variant was likely affected by tissue SP1 protein levels. Using an ordinary differential equation based on Michaelis-Menten kinetic assumptions, we modeled the dependence of PLA2G2A transcription on SP1 protein levels, incorporating the SNP influence. Collectively, our analysis strongly suggests that the difference in the binding dynamics of SP1 to different rs11573156 alleles may underlie the allele-specific PLA2G2A expression in different tissues, a mechanistic model that awaits future direct experimental validation. This mechanism likely contributes to the variation in circulating sPLA2-IIA protein levels in the human population, with implications for a wide range of human diseases.
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This paper proposes a new method for short-term electric load forecasting using a Ridgelet Neural Network (RNN) combined with a wavelet transform and optimized by a Self-Adapted (SA) Kho-Kho algorithm (SAKhoKho). The aim of this method is to improve the accuracy and reliability of electric load forecasting, which is essential for the planning and operation of competitive electrical networks. The proposed method uses the Wavelet Transform (WT) to decompose the load data into different frequency components and applies the RNN to each component separately. The RNN is, then, optimized by the SAKhoKho algorithm, which is an improved version of the KhoKho algorithm that can adapt the search parameters dynamically. The proposed method is trained and tested on the Zone Preliminary Billing Data from the PJM regulatory area, which is updated every two weeks based on the Intercontinental Exchange (ICE) figures. The proposed method is compared with six other cutting-edge methods from the literature, including SVM/SA, hybrid, ARIMA, MLP/PSO, CNN, and RNN/KhoKho/WT. The results show that the proposed method achieves the lowest Mean Absolute Error (MAE) of 7.7704 and Root Mean Square Error (RMSE) of 17.4132 among all the methods, indicating its superior performance. The proposed method can capture the temporal dependencies in the load data and optimize the RNN's weights to minimize the error function. The proposed method is a promising technique for electric load forecasting, as it can provide accurate and reliable predictions for the next hour based on the previous 24 h of data.
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Previous research suggests that group IIA-secreted phospholipase A2 (sPLA2-IIA) plays a role in and predicts lethal COVID-19 disease. The current study reanalyzed a longitudinal proteomic data set to determine the temporal relationship between levels of several members of a family of sPLA2 isoforms and the severity of COVID-19 in 214 ICU patients. The levels of six secreted PLA2 isoforms, sPLA2-IIA, sPLA2-V, sPLA2-X, sPLA2-IB, sPLA2-IIC, and sPLA2-XVI, increased over the first 7 ICU days in those who succumbed to the disease but attenuated over the same time period in survivors. In contrast, a reversed pattern in sPLA2-IID and sPLA2-XIIB levels over 7 days suggests a protective role of these two isoforms. Furthermore, decision tree models demonstrated that sPLA2-IIA outperformed top-ranked cytokines and chemokines as a predictor of patient outcome. Taken together, proteomic analysis revealed temporal sPLA2 patterns that reflect the critical roles of sPLA2 isoforms in severe COVID-19 disease.
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COVID-19 , SARS-CoV-2 , Humanos , COVID-19/mortalidad , COVID-19/sangre , Femenino , Masculino , Persona de Mediana Edad , Anciano , Fosfolipasas A2 Secretoras/sangre , Proteómica/métodos , Índice de Severidad de la Enfermedad , Fosfolipasas A2 Grupo II/sangre , Adulto , Isoformas de Proteínas/sangre , Citocinas/sangreRESUMEN
Blood purification, such as hemodialysis (HD), plasma exchange (PE), and hemoperfusion (HP), is widely applied in patients with organ failure (such as kidney and liver failure). Among them, HP mainly relies on porous adsorbents to efficiently adsorb accumulated metabolic wastes and toxins, thus improving purification efficiency. Metal-organic frameworks (MOFs), with a high porosity, large surface area, high loading capacity, and tailorable topology, are emerging as some of the most promising materials for HP. Compared with non-metal framework counterparts, the self-built metal centers of MOFs feature the intrinsic advantages of coordination with toxin molecules. However, research on MOFs in blood purification is insufficient, particularly in contrast to materials applied in other biomedical applications. Thus, to broaden this area, this review first discusses the essential characteristics, potential mechanisms, and structure-function relationship between MOFs and toxin adsorption based on porosity, topology, ligand functionalization, metal centers, and toxin types. Moreover, the stability, utilization safety, and hemocompatibility of MOFs are illustrated for adsorbent selection. The current development and progress in MOF composites for HD, HP, and extracorporeal membrane oxygenation (ECMO) are also summarized to highlight their practicability. Finally, we propose future opportunities and challenges from materials design and manufacture to the computational prediction of MOFs in blood purification. It is anticipated that our review will expand the interest of researchers for more impact in this area.
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Hemoperfusión , Estructuras Metalorgánicas , Humanos , Adsorción , Riñón , PorosidadRESUMEN
The introduction of carbonic anhydrase (CA) onto an extracorporeal membrane oxygenation (ECMO) membrane can improve the permeability of carbon dioxide (CO2). However, existing CA-grafting methods have limitations, and the hemocompatibility of current substrate membranes of commercial ECMO is not satisfactory. In this study, a 1-(3-dimethylaminopropyl)-3-ethylcarbodiimide hydrochloride (EDC)/N-hydroxy succinimide (NHS) activation method is adopted to graft CA with CO2-catalyzed conversion activity onto a polyethersulfone (PES) membrane, which is prepared by a phase inversion technique after in situ crosslinking polymerization of 1-vinyl-2-pyrrolidone (VP) and acrylic acid (AA) in PES solution. The characterization results reveal that CA has been grafted onto the modified PES membrane successfully and exhibits catalytic activity. The kinetic parameters of esterase activity verify that the grafted amount of active CA increases with an increase in the concentration of the CA incubation solution. The CA-grafted membrane (CA-M) can accelerate the conversion of bicarbonate to CO2 in water and blood, which demonstrates the special catalytic activity towards bicarbonate of CA. Finally, blood compatibility tests prove that the CA-M does not lead to hemolysis, shows suppressed protein adsorption and increased coagulation time, and is suitable for application in ECMO. This work demonstrates a green and efficient method for preparing bioactive materials and has practical guiding significance for subsequent pulmonary membrane research and ECMO applications.
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Anhidrasas Carbónicas , Polímeros , Sulfonas , Anhidrasas Carbónicas/metabolismo , Dióxido de Carbono , Bicarbonatos , Membranas Artificiales , Pulmón/metabolismoRESUMEN
Constructing effective and robust biocatalysts with carbonic anhydrase (CA)-mimetic activities offers an alternative and promising pathway for diverse CO2-related catalytic applications. However, there is very limited success has been achieved in controllably synthesizing CA-mimetic biocatalysts. Here, inspired by the 3D coordination environments of CAs, this study reports on the design of an ultrafast ZnN3-OH2 center via tuning the 3D coordination structures and mesoporous defects in a zinc-dipyrazolate framework to serve as new, efficient, and robust CA-mimetic biocatalysts (CABs) to catalyze the hydration reactions. Owing to the structural advantages and high similarity with the active center of natural CAs, the double-walled CAB with mesoporous defects displays superior CA-like reaction kinetics in p-NPA hydrolysis (V0 = 445.16 nM s-1, Vmax = 3.83 µM s-1, turnover number: 5.97 × 10-3 s-1), which surpasses the by-far-reported metal-organic frameworks-based biocatalysts. This work offers essential guidance in tuning 3D coordination environments in artificial enzymes and proposes a new strategy to create high-performance CA-mimetic biocatalysts for broad applications, such as CO2 hydration/capture, CO2 sensing, and abundant hydrolytic reactions.
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The secreted phospholipase A 2 (sPLA 2 ) isoform, sPLA 2 -IIA, has been implicated in a variety of diseases and conditions, including bacteremia, cardiovascular disease, COVID-19, sepsis, adult respiratory distress syndrome, and certain cancers. Given its significant role in these conditions, understanding the regulatory mechanisms impacting its levels is crucial. Genome-wide association studies (GWAS) have identified several single nucleotide polymorphisms (SNPs), including rs11573156, that are associated with circulating levels of sPLA 2 -IIA. Through Genotype-Tissue Expression (GTEx), 234 expression quantitative trait loci (eQTLs) were identified for the gene that encodes for sPLA 2 -IIA, PLA2G2A . SNP2TFBS ( https://ccg.epfl.ch/snp2tfbs/ ) was utilized to ascertain the binding affinities between transcription factors (TFs) to both the reference and alternative alleles of identified SNPs. Subsequently, ChIP-seq peaks highlighted the TF combinations that specifically bind to the SNP, rs11573156. SP1 emerged as a significant TF/SNP pair in liver cells, with rs11573156/SP1 interaction being most prominent in liver, prostate, ovary, and adipose tissues. Further analysis revealed that the upregulation of PLA2G2A transcript levels through the rs11573156 variant was affected by tissue SP1 protein levels. By leveraging an ordinary differential equation, structured upon Michaelis-Menten enzyme kinetics assumptions, we modeled the PLA2G2A transcription's dependence on SP1 protein levels, incorporating the SNP's influence. Collectively, these data strongly suggest that the binding affinity differences of SP1 for the different rs11573156 alleles can influence PLA2G2A expression. This, in turn, can modulate sPLA2-IIA levels, impacting a wide range of human diseases.
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Previous research suggests that group IIA secreted phospholipase A 2 (sPLA 2 -IIA) plays a role in and predicts severe COVID-19 disease. The current study reanalyzed a longitudinal proteomic data set to determine the temporal (days 0, 3 and 7) relationship between the levels of several members of a family of sPLA 2 isoforms and the severity of COVID-19 in 214 ICU patients. The levels of six secreted PLA 2 isoforms, sPLA 2 -IIA, sPLA 2 -V, sPLA 2 -X, sPLA 2 -IB, sPLA 2 -IIC, and sPLA 2 -XVI, increased over the first 7 ICU days in those who succumbed to the disease. sPLA 2 -IIA outperformed top ranked cytokines and chemokines as predictors of patient outcome. A decision tree corroborated these results with day 0 to day 3 kinetic changes of sPLA 2 -IIA that separated the death and severe categories from the mild category and increases from day 3 to day 7 significantly enriched the lethal category. In contrast, there was a time-dependent decrease in sPLA 2 -IID and sPLA 2 -XIIB in patients with severe or lethal disease, and these two isoforms were at higher levels in mild patients. Taken together, proteomic analysis revealed temporal sPLA 2 patterns that reflect the critical roles of sPLA 2 isoforms in severe COVID-19 disease.
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Chronic infected wound healing is a critical challenge in clinical practice owing to the involvement of multiple physiological processes, including bacteria-related, inflammatory regulation and angiogenesis. Therefore, a multi-functional strategy with synergistic anti-bacterial, anti-inflammatory and pro-angiogenic effects should be developed. Owing to their biomimetic structural features and controlled delivery of active agents, electrospun nanofilms are promising biomaterials for the treatment of skin defects. In this study, we fabricated multi-functional nanofilms with pro-angiogenic, anti-bacterial and anti-inflammatory capacities. First, strontium (Sr) ions were incorporated into poly(L-lactic-co-caprolactone) (PLCL) nanofilms. Subsequently, polydopamine (PDA) and zinc oxide (ZnO) were decorated onto the surface of Sr-loaded PLCL nanofilms to prepare ZnO/PDA@PLCL@Sr nanofilms. In vitro results showed that ZnO/PDA@PLCL@Sr nanofilms were biocompatible, exhibited angiogenic activity and significantly inhibited the growth of Staphylococcus aureus and Escherichia coli upon near-infrared -light irradiation. Furthermore, ZnO/PDA@PLCL@Sr nanofilms were found to drive the transformation of macrophages into the M2 phenotype. In vivo results further validated that ZnO/PDA@PLCL@Sr nanofilms exhibited pro-angiogenic and anti-bacterial activities and regulated inflammation to accelerate wound -healing in a rat model of bacteria-infected skin defects. In conclusion, we successfully developed a multi-functional biomaterial with pro-angiogenic, anti-bacterial and anti-inflammatory capacities to treat chronic infected wounds.
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Óxido de Zinc , Ratas , Animales , Óxido de Zinc/farmacología , Cicatrización de Heridas , Staphylococcus aureus , Escherichia coli , Materiales Biocompatibles/farmacología , Estroncio/farmacologíaRESUMEN
BACKGROUND: Low-cost and safe strategies to improve wound healing will be of great social and economic value. The goal of this pilot clinical trial is aimed at analyzing how effective insulin therapy is at healing wounds in nondiabetic people. METHODS: In this protocol research, 346 individuals were included. Patients were divided as 2 groups at random: experimental patients were given a ten-unit answer. For each 10 cm2 of wound, insulin was injected in solution with 1 mL 0.9 percent saline, whereas the control group got a standard dressing with normal saline. RESULTS: During the therapy period, no adverse effects were reported. After insulin therapy, no substantial insulin-related side effects were reduced. After 10 days of therapy, the experimental group's granulation tissue coverage rate and thickness were considerably improved as compared to control. Furthermore, a momentous difference in the occurrence of wound bleeding and suppurative wounds between the two groups (P = 0.05). CONCLUSION: The results of this pilot research suggest that insulin injections could harmless and effective alternative therapy for wound healing in nondiabetic individuals and that larger, placebo-controlled trials are needed to evaluate effectiveness and safety of insulin treatment in wound healing patients.
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Insulina/administración & dosificación , Cicatrización de Heridas/efectos de los fármacos , Administración Tópica , Adulto , Quemaduras/tratamiento farmacológico , Quemaduras/patología , Biología Computacional , Lesiones por Aplastamiento/tratamiento farmacológico , Lesiones por Aplastamiento/patología , Femenino , Tejido de Granulación/efectos de los fármacos , Tejido de Granulación/patología , Humanos , Inyecciones Intradérmicas , Laceraciones/tratamiento farmacológico , Laceraciones/patología , Masculino , Persona de Mediana EdadRESUMEN
Excessive bilirubin in the body of patient with liver dysfunction or metabolic obstruction may cause jaundice with irreversible brain damage, and new type of adsorbent for bilirubin is under frequent investigation. Herein, graphene oxide based core @ polyethersulfone-based shell beads are fabricated by phase inversion method, amides and heparin-like polymer are introduced to functionalize the core-shell beads. The beads are successfully prepared with obvious core-shell structure, adequate thermostability and porous shell. Clotting times and protein adsorption are investigated to inspect the hemocompatibility property of the beads. The adsorption of bilirubin is systematically investigated by evaluating the effects of contacting time, initial concentration and temperature on the adsorption, which exhibits improved bilirubin adsorption amount for the beads with amides contained cores or/and shells. It is worth believing that the amides and heparin-like polymer co-functionalized core-shell beads may be utilized in the field of hemoperfusion for bilirubin adsorption.
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Amidas/química , Bilirrubina/aislamiento & purificación , Grafito/química , Heparina/química , Polímeros/química , Sulfonas/química , Adsorción , Humanos , Cinética , Espectroscopía Infrarroja por Transformada de Fourier , Temperatura , TermogravimetríaRESUMEN
An environmental strategy for developing sustainable materials presents an attractive prospect for wastewater remediation. Herein, a facile, green, and economical strategy is proposed to fabricate magnetic composite nanoparticles (NPs) toward cationic dye adsorption and selective degradation. To prepare the composite TiO2-PEI-TA@Fe3O4 NPs, tannic acid (TA) and polyethyleneimine (PEI) were first used to decorate Fe3O4 NPs at aqueous solution, and then TiO2 NPs were anchored onto the surfaces of Fe3O4 NPs based on the catecholamine chemistry. The chemical composition and microstructure of the obtained NPs were systematically characterized. The NPs not only exhibited adsorption ability for the cationic dye of methylene blue (MB) but also responded to ultraviolet light to selectively degrade the adsorbed MB, and the removal (adsorption and/or degradation) ratio for MB could reach 95%. In addition, cyclic experiments showed that the removal ratio of the composite NPs for MB could still be maintained more than 85% even after five cycles. Given by the above-mentioned advantages, such a green and facile strategy for combining the adsorption and degradation methods to construct magnetic nanocomposites exhibits potential applications in cationic dye selective removal and sustainable wastewater remediation.
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Current therapy for liver failure and concomitant hyperbilirubinemia faces the challenge of poor hemocompatibility and bleeding risks associated with the anticoagulant injection. Herein, heparin-mimetic biomacromolecule (HepMBm) with a similar degree of sulfation and anticoagulant properties to heparin was synthesized by imitating the structure of natural biomacromolecule heparin. Then HepMBm was used to prepare nanocomposite spheres based on reduced graphene oxide (rGO). The formation of a dual-network structure in the spheres endowed the spheres with improved dimensional stability. The proposed spheres exhibited outstanding blood compatibilities and excellent self-anticoagulant properties. The bilirubin adsorption experiments and whole blood bilirubin removal assay indicated that the spheres exhibited high bilirubin removal capability from whole blood (The removal ratio was 99.69%.). The spheres open new routes for a therapeutic strategy without a plasma separation system and heparin pump, which may be a step toward a lightweight wearable artificial liver.
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Hígado Artificial , Nanocompuestos , Dispositivos Electrónicos Vestibles , Anticoagulantes/farmacología , BilirrubinaRESUMEN
Adsorbents are usually used to remove uremic toxins for blood purification. However, the removal of urea is still an intractable problem, since no effective material has been found for urea removal by physical adsorption. Here, urease immobilized graphene oxide core@shell heparin-mimicking polymer (U-GO-HMP) beads were designed, which exhibited good urea removal ability with a removal amount of about 635 mg/g and a removal ratio of about 80% from urea solution. In addition, urea could be removed from collected dialysate and the removal ratio could reach 60% within 480 min. Beyond that, the U-GO-HMP beads also showed good reusability with sustainable relative activity after 5 cycles. Furthermore, the U-GO-HMP beads exhibited good blood compatibility with low hemolysis ratio, suppressed complement activation and contact activation, as well as increased clotting times. It is worthy believing that the U-GO-HMP beads may have great potential in the field of blood purification for urea removal.
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Materiales Biomiméticos/química , Enzimas Inmovilizadas/química , Grafito/química , Heparina/química , Microesferas , Urea/aislamiento & purificación , Ureasa/química , Enzimas Inmovilizadas/metabolismo , Humanos , Seguridad , Urea/sangre , Ureasa/metabolismoRESUMEN
Given the complexity of pollutants in wastewater, development of facile and effective multifunctional materials, which can not only kill bacteria but also remove dyes from wastewater, is in high demand. Herein, a facile strategy for the preparation of positively-charged nanofibrous membranes (NFMs) is reported via the combination of electrospinning and in-situ cross-linked polymerization of poly ([2-(methacryloyloxy)-ethyl] trimethyl ammonium chloride) (PMETAC) in poly (ether sulfone) (PES) solution. The quaternary ammonium salt polymer of PMETAC enabled the NFMs with positive charge to kill bacteria and remove anionic dyes. The antibacterial tests including agar plate counting and live/dead staining indicate that the NFMs show strong antibacterial ability with bacterial killing ratios of nearly 99% for both Escherichia coli and Staphylococcus aureus, as well as remarkable recyclability towards killing bacteria. The dyes adsorption experiments show that the NFMs exhibit high adsorption capacity for anionic dyes up to 208â¯mgâ¯g-1 for Congo Red (CR) and good reusability toward CR. Impressively, the membrane adsorption column test indicates that the CR dye removal ratio is up to 100% for the first time, and that is still as high as 96.5% for the third time with a fresh dye solution. Given the above advantages, such fascinating NFMs may provide new perspectives in the exploitation of multifunctional membrane materials for complex water remediation.
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Antibacterianos/química , Colorantes/química , Escherichia coli/crecimiento & desarrollo , Membranas Artificiales , Nanofibras/química , Polímeros/química , Staphylococcus aureus/crecimiento & desarrollo , Sulfonas/química , Aguas Residuales , Adsorción , Aguas Residuales/química , Aguas Residuales/microbiologíaRESUMEN
Postoperative adhesion may form as the result of a complicated fibrosis and inflammatory response, thus leads to a series of complications or increases the risk of surgery failure. Herein, we prepared poly (lactic-co-glycolic acid)-graft-polyvinylpyrrolidone/polyiodide (PLGA-g-PVP/I) electrospun fibrous membranes to prevent postoperative adhesion and infection formation. Firstly, hydrophilic PVP molecules were grafted on the surface of PLGA powders by gamma ray, and then iodine ions were coordinated with the grafted PVP. Subsequently, PLGA-g-PVP/I fibrous membranes were prepared by electrospinning. The PLGA-g-PVP/I membranes were analyzed via UV-vis, FTIR, Raman, and XPS. The formed polyiodide endowed the membranes with sustained antibacterial activity. The antimicrobial property of PLGA-g-PVP/I membranes was ascribed to the synergistic effect of intracellular ROS production and glutathione oxidation. Furthermore, the prevention efficacy of postoperative abdominal adhesion from the PLGA-g-PVP/I composite membranes was characterized in a rat model of sidewall defect-cecum abrasion. The results demonstrated that the PLGA-g-PVP/I fibrous membranes could prevent the postoperative abdominal adhesion effectively. Therefore, to endow the PLGA-g-PVP/I electrospun fibrous membranes with durable antibacterial property may be a promising strategy towards an anti-bacterial and anti-adhesion system for commercial and clinical uses.
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Antibacterianos/farmacología , Materiales Biocompatibles/farmacología , Escherichia coli/efectos de los fármacos , Ácido Peryódico/química , Copolímero de Ácido Poliláctico-Ácido Poliglicólico/farmacología , Povidona/química , Animales , Antibacterianos/química , Materiales Biocompatibles/química , Proliferación Celular/efectos de los fármacos , Fibroblastos/efectos de los fármacos , Ratones , Pruebas de Sensibilidad Microbiana , Estrés Oxidativo/efectos de los fármacos , Copolímero de Ácido Poliláctico-Ácido Poliglicólico/química , Ratas , Rayos UltravioletaRESUMEN
The adsorbents with high adsorption capacity are in urgent demand for water treatment because of the global freshwater crisis. In this work, the copolymer of acrylic acid and methyl methacrylate was synthesized at first, and subsequently blended with polyethersulfone (PES) with different mass ratios to prepare functionalized PES nanofibrous membranes via one-step electrospinning method. Benefiting from the abundant carboxyl groups, as well as the large specific surface area and high porosity, the nanofibrous membranes exhibited a maximum adsorption capacity of 2257.88â¯mgâ¯g-1 for methylene blue (MB) dyes, which was among the largest adsorption amount of those previously reported adsorbents. In addition, the adsorption process was systematically investigated under various conditions, including pH, initial MB concentrations and contact time. Meanwhile, the pseudo-second-order model and Langmuir isotherm model was very suitable to describe the adsorption kinetics and isotherm, respectively. Moreover, the nanofibrous membranes also exhibited excellent recyclability (81.45% after 5 cycles), high filtration-purification efficiency (above 99%, at a high flux of 100â¯mLâ¯min-1) and selective adsorption and separation abilities. These excellent performances endow the nanofibrous membranes with promising potential applications for dye wastewater treatment.
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Although abundant works have been developed in mussel-inspired antifouling coatings, most of them suffer from poor chemical stability, especially in a strongly alkaline environment. Herein, we report a robust one-step mussel-inspired method to construct a highly chemical stable and excellent antibiofouling membrane surface coating with a highly efficient codeposition of polydopamine (PDA) with zwitterionic polymer. In the study, PDA and polyethylenimine-quaternized derivative (PEI-S) are codeposited on the surface of poly(ether sulfone) (PES) ultrafiltration membrane in water at room temperature. In contrast to individual PDA coating, the obtained PDA/PEI-S coating exhibits excellent chemical stability even in a strongly alkaline environment owing to the cross-linking and unexpected cation-π interaction between the PEI-S and PDA. Thanks to the introduction of PEI-S, systematic protein adsorption tests and bacteria adhesion experiments demonstrated that the surfaces could prevent bovine serum fibrinogen and lysozyme adsorption and could reduce Gram-positive bacteria S. aureus and Gram-negative bacteria E. coli adhesion. Benefiting from the versatile functionality of PDA, the proposed strategy is not limited to PES membrane surface but also others such as poly(ethylene terephthalate) sheets and commercial polypropylene microfiltration membranes. Overall, this work enriches the exploration of a remarkable coating with enhanced stability and excellent antifouling property via a facile, robust, and material-independent approach to modifying the membrane surface.
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Multifunctional materials, which can effectively and simultaneously remove various water-soluble contaminants like dyes and heavy metal ions, and separate oil from water, are urgent to meet increasing challenges on wastewater remediation. Herein, a cross-linked poly (acrylic acid) (PAA) modified poly (ether sulfone) nanofibrous membrane (NFM) was fabricated by a facile in-situ pre-reaction followed by electrospinning. The as-prepared NFM showed excellent hydrophilicity and underwater lipophobicity, therefore expressed excellent water permeability with high water flux (about 5142â¯Lâ¯m2â¯h-1). As a result, under solely driven by gravity, the NFM was capable to separate emulsified oil/water emulsion and a wide range of oil/water mixtures. Moreover, repeating separation tests indicated that the NFM had great long-term sustainability even after ten separation cycles. In addition, due to the introduction of PAA and the large surface-to-volume ratio, the NFM also expressed rapid adsorption capacity for cationic dyes as well as heavy metal ions; thus could simultaneously remove these contaminants during the oil/water separation process. Furthermore, the NFM could be also decorated by Ag NPs to endow the membranes with remarkable antibacterial ability against both E. coli and S. aureus. Our findings strongly suggested that the multifunctional NFM may have great potential in treating complicated wastewater.