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1.
ACS Appl Mater Interfaces ; 12(12): 13698-13708, 2020 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-32129070

RESUMO

Recent emerged metal-organic frameworks (MOFs), as superior drug carriers, provide novel strategies to combat pathogenic bacterial infections. Although various antibacterial metal ions can be easily introduced in MOFs for chemical bacterial ablation, such a single-model bactericidal method suffers from high-dose use, limited antibacterial efficiency, and slow sterilization rate. Hence, developing a dual bactericidal system is urgently required. Herein, we report an MOF/Ag-derived nanocomposite with efficient metal-ion-releasing capability and robust photo-to-thermal conversion effect for synergistic sterilization. The MOF-derived nanocarbon consisting of metallic zinc and a graphitic-like carbon framework is first synthesized, and then Ag nanoparticles (AgNPs) are evenly introduced via the displacement reaction between Zn and Ag+. Upon near-infrared irradiation, the fabricated nanoagents can generate massive heat to destroy bacterial membranes. Meanwhile, abundant Zn2+ and Ag+ ions are released to make chemical damage to bacterial intracellular substances. Systematic antibacterial experiments reveal that such dual-antibacterial effort can endow the nanoagents with nearly 100% bactericidal ratio for highly concentrated bacteria at a very low dosage (0.16 mg/mL). Furthermore, the nanoagents exhibit less cytotoxicity, which provides potential possibilities for the applications in the biological field. In vivo assessment indicates that the nanocomposites can realize rapid and safe wound sterilization and are expected to be an alternative to antibiotics. Overall, we present an easily fabricated structure-engineered nanocomposite with chemical and photothermal effects for broad-spectrum bacterial sterilization.

2.
J Mater Chem B ; 8(9): 1960-1970, 2020 Mar 04.
Artigo em Inglês | MEDLINE | ID: mdl-32067017

RESUMO

Recently emerged hemoperfusion absorbents, e.g. ion-exchange resin, activated carbon, and other porous materials, provide numerous novel possibilities to cure chronic liver failure (CLF) and renal failure (CRF). However, the limited adsorption performance and unsatisfactory blood compatibility significantly impede the development of the absorbents. Hence, designing safe and self-anticoagulant hemoperfusion absorbents with robust toxin clearance remains a considerable challenge. Here, brand new Kevlar-based composite gel beads for hemoperfusion are prepared by interface assembly based on π-π interaction. First, Kevlar nanofiber-graphene oxide (K-GO) beads are produced by liquid-liquid phase separation. Then, sodium p-styrenesulfonate (SS) is adsorbed onto the K-GO interface by π-π interaction and initiated to achieve the composite gel (K-GO/PSS) beads with an interfacial crosslinked structure. Such composite gel beads possess superior mechanical strength and self-anticoagulation capability, owing to the dual-network structure and heparin-mimicking gel structure, respectively. Furthermore, the K-GO/PSS beads show robust adsorption capacities for different kinds of toxins due to their strong charge and π-π interactions. A simulated hemoperfusion experiment in vitro demonstrates that the concentrations of the toxins in the blood can be restored to normal values within 30 minutes. In general, we envision that such composite gel beads will provide new strategies for future clinical CLF and CRF treatments.

3.
Fish Shellfish Immunol ; 99: 526-534, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32097718

RESUMO

Tributyltin chloride (TBT-Cl) residual in water body had become a noticeable ecological problem for aquatic ecosystems. Toll-like receptors (TLRs) are an ancient family of pattern recognition receptors that play key roles in detecting nonself antigens and immune system activation. In this study, we explored the effect of TBT-Cl exposure on four TLRs expression in river pufferfish, Takifugu obscurus. The four T. obscurus Toll-like receptors (To-TLRs) contained different types of domains such as leucine-rich repeats (LRRs), leucine-rich repeats, typical subfamily (LRR_TYP) and other special domains. The To-TLRs mRNA transcripts expressed in all tissues, also To-TLR2 was investigated with higher level in kidney, as well as To-TLR3 in kidney, while To-TLR18 in liver and To-TLR22 in intestine. After the acute and chronic exposure of TBT-Cl, To-TLR2 and To-TLR3 mRNA transcripts were significantly down-regulated in gill. However, To-TLR18 and To-TLR22 were significantly up-regulated in gill and liver. Moreover, the histology and immunohistochemistry (IHC) results showed the different injury degrees of TBT-Cl in liver and gill and implied the cytoplasm reorganization after TBT-Cl stress and the function of immunoregulation for To-TLRs to TBT-Cl exposure. All the results indicated that To-TLRs might involve in sensing and mediating innate immune responses caused by TBT-Cl for keeping detoxification homeostasis.

4.
Int J Mol Sci ; 21(2)2020 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-31968672

RESUMO

Cancer is one of the most serious diseases endangering human health. In view of the side effects caused by chemotherapy and radiotherapy, it is necessary to develop low-toxic anti-cancer compounds. Polyphenols are natural compounds with anti-cancer properties and their application is a considerable choice. Pro-senescence therapy is a recently proposed anti-cancer strategy and has been shown to effectively inhibit cancer. It is of great significance to clarify the mechanisms of polyphenols on tumor suppression by inducing senescence. In this review, we delineated the characteristics of senescent cells, and summarized the mechanisms of polyphenols targeting tumor microenvironment and inducing cancer cell senescence for cancer prevention and therapy. Although many studies have shown that polyphenols effectively inhibit cancer by targeting senescence, it warrants further investigation in preclinical and clinical studies.

5.
Biomacromolecules ; 2020 Jan 28.
Artigo em Inglês | MEDLINE | ID: mdl-31955566

RESUMO

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.

6.
Colloids Surf B Biointerfaces ; 186: 110728, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31862559

RESUMO

In this study, we proposed a green, facile and low-cost approach for the fabrication of multifunctional particles with robust bacteria removal capability and on-demand biofilm eradication activity. Based on mussel-inspired coating of catechol and hexanediamine on Fe3O4 in aqueous solution, magnetic poly(catechol-hexanediamine) particles (Fe3O4@HDA) were prepared successfully in 1 h, at room temperature. Microbiological experiments demonstrated the Fe3O4@HDA particles could capture bacteria in water efficiently. Meanwhile, with an integration of magnetic response property and near-infrared-triggered photothermal bactericidal activity, the Fe3O4@HDA particles showed a high potential for biofilm targeting and in-situ eradication. We believe that the rationally designed magnetic poly(catechol-hexanediamine) particles could extend the applications of smart antimicrobial agents to industrial fields such as water disinfection and biofouling clean-up.

7.
J Mater Chem B ; 8(3): 568-577, 2020 Jan 22.
Artigo em Inglês | MEDLINE | ID: mdl-31854426

RESUMO

Rapid endothelialization and prevention of restenosis are two vital challenges for the preparation of a small-diameter vascular graft (SDVG), while postoperative infection after implantation is often neglected. In the present study, carboxymethyl chitosan (CMC) and chitosan (CS) were chosen as the anti-thrombotic and anti-bacterial components, respectively; and then an asymmetric vascular graft was fabricated by co-electrospinning of poly(ε-caprolactone) (PCL)/CMC and PCL/CS. The mechanical properties of the asymmetric vascular graft were much better than those of the native vessels. In vitro blood compatibility tests indicated that the inner layer of the graft could inhibit thrombosis effectively. The outer layer of the graft had a certain anti-bacterial effect owing to the addition of chitosan. Besides, the inner layer of the graft could greatly promote the growth of endothelial cells. It is believed that the asymmetric SDVG with anti-thrombotic and anti-bacterial functions could contribute to the future clinical implantation of tissue engineered vascular grafts.

8.
Int J Biol Macromol ; 2019 Nov 26.
Artigo em Inglês | MEDLINE | ID: mdl-31783078

RESUMO

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.

9.
J Colloid Interface Sci ; 556: 492-502, 2019 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-31473539

RESUMO

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 208 mg 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.


Assuntos
Antibacterianos/química , Corantes/química , Escherichia coli/crescimento & desenvolvimento , Membranas Artificiais , Nanofibras/química , Polímeros/química , Staphylococcus aureus/crescimento & desenvolvimento , Sulfonas/química , Águas Residuárias , Adsorção , Águas Residuárias/química , Águas Residuárias/microbiologia
10.
Artigo em Inglês | MEDLINE | ID: mdl-31411370

RESUMO

The current challenge for polymersomes is to prepare amphiphilic block polymers with not only well-defined molecular weight, but also precisely high-order multiblock structure in terms of the distribution of monomeric units along the chain. Here, we describe a synthesis of temperature-responsive polymersomes with precisely defined membrane structures using high-precision amphiphilic multiblock polymer via aqueous single electron transfer living radical polymerization (SET-LRP) in which poly(ethylene glycol) (PEG) macromolecules are used as initiators. We develop a one-pot, rapid and multistep sequential polymerization process with yields >99% within 30 min for each block, giving access to a wide range of high-precision multiblock polymers with very narrow molecular weight distributions (Ð ≤ 1.14). Synthesized multiblock polymers are used to form nano-sized polymersomes which are highly promising as smart carriers for high loading and triggered release of biopharmaceutics such as pharmaceutical proteins and peptides. This synthesis approach is environmentally friendly, fully translation and thus represents a significant advance in the design and synthesis of a new generation of polymer nanomaterials with precisely defined structures, which is highly attractive for applications in nanotechnology.

11.
J Mater Chem B ; 7(36): 5520-5527, 2019 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-31432876

RESUMO

The prevention of bacteria-induced infections has been increasing in importance in both clinical surgery and biomedical engineering. Although great attention has been paid to designing intelligent antibacterial surfaces, the fabrication processes are still not facile and universal enough, and the antibacterial efficiencies of these surfaces are also not ideal. Herein, ionic liquid (IL) molecules of 3-(12-mercaptododecyl)-1-methyl-1H-imidazol-3-ium bromide (IL(Br)) were synthesized with the minimum inhibitory concentrations as low as 4 and 8 µg mL-1 against Staphylococcus aureus (S. aureus) and Escherichia coli (E. coli), respectively. By simply immersing a polymeric substrate into the IL(Br) solution, an antibacterial surface with high killing efficiency of 99% against S. aureus (94% against E. coli) was achieved via a mussel-inspired approach. Subsequently, 97% S. aureus and 95% E. coli on the substrate could be released by simple ion-exchange of Br- with (CF3SO2)2N- due to the ion sensitivity of the IL molecular brushes. Thus, the proposed facile strategy towards a superior efficiency surface could be potentially used in intelligent antibacterial fields.

12.
Colloids Surf B Biointerfaces ; 181: 918-926, 2019 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-31382341

RESUMO

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.


Assuntos
Antibacterianos/farmacologia , Materiais Biocompatíveis/farmacologia , Escherichia coli/efeitos dos fármacos , Ácido Periódico/química , Copolímero de Ácido Poliláctico e Ácido Poliglicólico/farmacologia , Povidona/química , Animais , Antibacterianos/química , Materiais Biocompatíveis/química , Proliferação de Células/efeitos dos fármacos , Fibroblastos/efeitos dos fármacos , Camundongos , Testes de Sensibilidade Microbiana , Estresse Oxidativo/efeitos dos fármacos , Copolímero de Ácido Poliláctico e Ácido Poliglicólico/química , Ratos , Raios Ultravioleta
13.
Langmuir ; 35(28): 9161-9168, 2019 Jul 16.
Artigo em Inglês | MEDLINE | ID: mdl-31265304

RESUMO

Applications of effective and steady metal catalysts for the hydrogen evolution reaction (HER) via electrolysis of water have a huge potential to relax energy crisis and reduce carbon dioxide emission. Herein, we design a simple, facile, and general approach for the synthesis of a series of transition-metal phosphide nanoparticles embedded in N-doped carbon (NC) nanomaterials using metal salts, abundantly available hexamethylene diamine tetra(methyl phosphonic acid), and urea as precursors. The resultant transition-metal phosphide nanoparticles can serve as high-efficiency and steady HER catalysts. Particularly, when the current density is 10 mA cm-2, the overpotentials of the obtained RhP2@NC are 30, 85, and 70 mV in acid (0.5 M H2SO4), neutral (1 M PBS), and alkaline (1 M KOH) solutions, respectively. Besides, the RhP2@NC exhibits good stability after 10 h in aforementioned solutions. More importantly, it is suited to fabricate other transition-metal phosphide nanoparticles/NC heterostructures by this synthetic strategy. The obtained CoP@NC, FeP@NC, Ni2P@NC, and Cu3P@NC also show relatively high efficiency for HER. Hence, the versatile synthesis strategy opens a new route for the research and fabrication of transition-metal phosphide-based catalysts for HER.

14.
Biomacromolecules ; 20(8): 3057-3069, 2019 Aug 12.
Artigo em Inglês | MEDLINE | ID: mdl-31306012

RESUMO

Nonadherent wound dressings with moisture management and long-lasting antibacterial properties have great significance for wound healing clinically. Herein, a novel multicomponent zwitterionic gradational membrane is fabricated by a co-electrospinning method to realize low biofouling and favorable moisture control as well as long-acting antibacterial properties during the chronic wound-healing process. The obtained membrane possesses excellent anti-biofouling performance that effectively resists protein, bacteria, and cell adhesion according to in vitro antifouling evaluation. Furthermore, the gradational co-electrospinning method grants the composite membrane with moisture retention capability which could effectively absorb wound exudate and maintain a moisture healing environment. Additionally, in vivo and in vitro antibacterial investigations reflect that the composite membrane has excellent long-acting antibacterial property. Moreover, in vivo wound healing assessment confirms that the prepared membrane significantly reduces the complete wound healing time than commercial wound dressing. These results highlight such a zwitterionic gradational membrane as an advanced wound dressing to meet the various requirements for chronic wound infection and skin tissue regeneration in clinical applications.

15.
Chemosphere ; 234: 25-33, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31202176

RESUMO

Mountain rivers not only play an important role in flood control, but also perform other functions such as conserving water sources, regulating microclimate, and maintaining water ecology and biodiversity. Because the conventional approach to managing mountain rivers overlooks the intrinsic requirements of river water, alters the natural landscape of river channels, and destroys habitats, it leads to water quality deterioration and ecological imbalance. The Yang River is characteristic of northern mountain rivers, and so the ecological management project for this river - at the site of the forthcoming Beijing 2022 Olympic Winter Games - was selected as an example of comprehensive ecological management. This comprises an ecological, permeable dam-pond-wetland system. Results showed that: (Zhu et al., 2006): river water quality improved substantially; improvements in the water quality indices exhibited the trend suspended solids (SS) > ammonium-nitrogen (NH3-N) > chemical oxygen demand (COD) (Mikus et al., 2019). The Shannon-Wiener diversity index, Margalef species richness index, and Pielou evenness index all indicated increased phytoplankton by an average of 52.1%, 2.4%, and 98.9%, respectively. These three diversity indices showed increased zooplankton, by an average of 1.2%, 0.5%, and 3.3%, respectively. Water quality in the Yang River was found to have changed from moderate to light pollution (Kuemmerlen et al., 2019). Each subsystem increased removal of pollutants from the Yang River. Removal efficiencies of COD, total phosphorous (TP), total nitrogen (TN), NH3-N, and SS by the dam system were 28.57%, 28.3%, 20.5%, 24.0%, and 95%, respectively. Corresponding pollutant removal efficiencies by the pond system were 16.7%, 29.58%, 21.63%, 20.0%, and 99.8%, respectively. The wetland system achieved pollutant removal efficiencies of 44.0%, 17.1%, 6.7%, 13.9%, and 80.0%, respectively. This approach can mitigate flood control pressure, restore river ecology, and improve water quality in northern mountain rivers, and allow such rivers to achieve "retention-storage-restoration" effects. The ecological treatment approach provides an important theoretical foundation and technical reference for global mountain river management, and is especially applicable to mountain rivers in cold and arid regions in the northern hemisphere.


Assuntos
Medição de Risco/métodos , Rios/química , Estações do Ano , Poluentes Químicos da Água/análise , Qualidade da Água , China , Ecossistema
16.
J Control Release ; 304: 39-50, 2019 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-31054990

RESUMO

The high level of bone metabolism associated with osteopenia and multifocal skeletal fracture remains a challenging clinical problem in osteoporosis patients. Salmon calcitonin (sCT), as a peptide medicine, is able to inhibit osteoclast activity and stimulate osteoblast growth. However, calcitonin receptors (CTRs) are widely distributed in vivo, limiting the specificity and therapeutic effects. Here, we report a bone-seeking hexapeptide (Asp6)-conjugated sCT (sCT-Mal-Asp6) for the targeted treatment of osteoporosis. The sCT-Mal-Asp6 was synthesized via a disulfide re-bridge reaction with high specificity and purity. It was demonstrated that the adsorption of sCT-Mal-Asp6 on hydroxyapatite (HA) was about 5.4 times higher than that of sCT. It was demonstrated a prolonged circulation time and 3-fold higher femur tissue accumulation of sCT-Mal-Asp6. In ovariectomized (OVX) models, sCT-Mal-Asp6 significantly increased the ability to attenuate hypercalcemia and reconstruct the trabecula. Our work provides an efficient approach to targeted and effective osteoporosis treatment.

17.
Nano Lett ; 19(9): 5885-5896, 2019 09 11.
Artigo em Inglês | MEDLINE | ID: mdl-31117696

RESUMO

Recently emerging graphene-based 2D nanoplatforms with multiple therapeutic modalities provide enormous opportunities to combat pathogenic bacterial infections. However, because these materials suffer from complicated synthesis, massive dosage requirements, and abundant nonlocalized heat, much more simplified, tunable, and localized eradication approaches are urgently required. Herein, we report on the fabrication of the metal-organic-framework (MOF)-derived 2D carbon nanosheets (2D-CNs) with phase-to-size transformation and localized bacterial eradication capabilities for augmented anti-infective therapy. The MOF-derived, ZnO-doped carbon on graphene (ZnO@G) is first synthesized and then anchored with phase transformable thermally responsive brushes (TRB) by in situ polymerization to yield the TRB-ZnO@G. The TRB-ZnO@G exhibits flexible 2D nanostructures, high photothermal activities, sustained Zn2+ ions release, and ON-OFF switchable phase-to-size transformation abilities. Notably, the near-infrared-triggered formation of TRB-ZnO@G-bacteria aggregations enables localized massive Zn2+ ions penetration, physical cutting, and hyperthermia killing, which synergistically enhance the disruption of bacterial membranes and intracellular substances. The obtained novel 2D-CNs not only present robust and localized multiple bacterial eradication capabilities with nearly 100% bactericidal efficiency at low concentrations but also possess rapid and safe skin wound disinfection via a short-time photothermal treatment without damaging normal skin tissues or causing accumulative toxicities, thus presenting great potential for broad-spectrum eradication of pathogenic bacteria.

18.
Mater Sci Eng C Mater Biol Appl ; 96: 402-411, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30606548

RESUMO

Intensive efforts have been employed in modifying biomedical membranes. Among them, blending is recognized as a simple method. However, the conventional blending materials commonly lead to an insufficient modification, which is mainly caused by the poor miscibility between the blending materials and the matrixes, the elution of the hydrophilic materials from the matrixes during the use and storage, and the insufficient surface enrichment of the blending materials. Aiming to solve the abovementioned disadvantages, we developed novel polyethersulfone/poly(acrylic acid-co-N-vinyl-2-pyrrolidone) networked submicrogels (PES/P(AA-VP) NSs), which were blended with PES to enhance the antifouling properties, antibacterial adhesion and haemocompatible properties of PES membranes. As results, the PES/P(AA-VP) NSs showed good miscibility with the PES matrix, and hydrophilic submicrogels would enrich onto the membrane surface during the phase inversion process due to the surface segregation. The entanglement between the PES matrix and the networked submicrogels would effectively limit the elution of the submicrogels. In conclusion, the modified PES membranes prepared by blending with the PES/P(AA-VP) NSs might draw great attention for the application in haemodialysis fields.


Assuntos
Antibacterianos , Aderência Bacteriana/efeitos dos fármacos , Escherichia coli/crescimento & desenvolvimento , Teste de Materiais , Membranas Artificiais , Polímeros , Staphylococcus aureus/crescimento & desenvolvimento , Sulfonas , Animais , Antibacterianos/química , Antibacterianos/farmacologia , Linhagem Celular , Géis , Humanos , Camundongos , Polímeros/química , Polímeros/farmacologia , Sulfonas/química , Sulfonas/farmacologia
19.
Environ Sci Pollut Res Int ; 26(33): 33946-33952, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-30032368

RESUMO

Black-odor rivers have become a prominent environmental problem, especially for developing countries. A laboratory experiment was conducted to determine the optimum operating parameters of artificial aquatic plants (AAP) to provide a theoretical and scientific basis for their application in black-odor rivers. The purification mechanism of operating parameters for AAP was also explored at the micro-organic and genetic levels by high-throughput sequencing. Chemical oxygen demand (COD) and ammonia nitrogen (NH4+-N) were measured in systems with different AAP lengths and pH. After 24 days, the best removal efficiencies of APP for COD and NH4+-N were 90.07 and 82.40% for 100 cm and 90.70 and 91.90% for pH values of 8.0-9.0, respectively. High-throughput sequencing analysis revealed that the relative abundance of Flavobacterium in the AAP was 7.80% at 50 cm, while the proportion increased to 29.30% at 100 cm. The abundance of microorganisms improved continuously with increased length, and the ratio of Acinetobacter increased obviously at pH 8.0-9.0 relative to pH 6.0-7.0. Furthermore, the AAP were used in Qihe Artificial Wetland in Shandong Province, China. The results revealed that the average removal efficiencies of AAP for COD and NH4+-N were 27.75 and 14.34%, respectively, in the artificial wetland. Therefore, AAP was beneficial to the growth of bacteria and could be used in the treatment of black-odor rivers.


Assuntos
Biodegradação Ambiental , Poluentes da Água/análise , Amônia/análise , Análise da Demanda Biológica de Oxigênio , China , Nitrogênio/análise , Odorantes/análise , Rios/química , Poluição da Água/estatística & dados numéricos , Áreas Alagadas
20.
J Colloid Interface Sci ; 533: 526-538, 2019 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-30179831

RESUMO

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 2257.88 mg 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 100 mL 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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