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1.
Environ Res ; 249: 118410, 2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38342204

RESUMO

With widespread and excessive use of antibiotics in medicine, poultry farming, and aquaculture, antibiotic residues have become a significant threat to both eco-environment and human health. In this paper, using hydroxyapatite nanowires (HApNWs) as an ecologically compatible carrier, a novel nano-hammer shaped conjunction with HApNW conjugating CuO microspheres (CuO@HApNWs) was successfully synthesized by in-situ agglomeration method. The catalytic degradation performance of the nano-hammer shaped CuO@HApNWs with Fenton-like activation was investigated by using tetracycline (TC) as a representative antibiotic pollutant. Remarkably, it exhibited excellent catalytic activity, which the removal rate of TC got to 92.0% within 40 min, and the pseudo-second-order reaction kinetic constant was 18.33 × 10-3 L mg-1·min-1, which was 26 times and 5 times than that of HApNWs and CuO, respectively. Furthermore, after recycling 6 times, the degradation efficiency of TC still remained above 85 %. Based on radical scavenger tests and electron paramagnetic resonance (EPR) spectroscopy, it demonstrated that the excellent activity of CuO@HApNWs was mainly attributed to the fact that Fenton-like activation promotes the circulation of Cu2+ and Cu+, the generated main active oxygen species (•OH and O2-•) achieve efficient degradation of TC. In summary, the nano-hammer shaped CuO@HApNWs could be in-situ synthesed, and used as an eco-friendly Fenton-like catalyst for effectively catalytic degradation of organic pollutants, which has great potential for wastewater treatment.


Assuntos
Antibacterianos , Cobre , Nanofios , Tetraciclina , Poluentes Químicos da Água , Cobre/química , Tetraciclina/química , Catálise , Antibacterianos/química , Nanofios/química , Poluentes Químicos da Água/química , Durapatita/química
3.
Langmuir ; 40(1): 125-132, 2024 01 09.
Artigo em Inglês | MEDLINE | ID: mdl-38105614

RESUMO

Bacterial infection of medical devices has caused incalculable losses to maintenance costs and health care. A single coating with antibacterial function cannot guarantee the long-term use of the device, because the coating will be damaged and fall off during reuse. To solve this problem, the development of coatings with high adhesion and self-healing ability is a wise direction. In this paper, a multifunctional polyzwitterionic antibacterial hydrogel coating (PZG) composed of amphozwitterion monomer, anionic monomer, and quaternary ammonium cationic monomer was synthesized by dipping UV photoinitiated polymerization. The structure of PZGs was characterized by Fourier transform infrared spectroscopy, scanning electron microscopy, energy-dispersive X-ray spectroscopy, and X-ray photoelectron spectroscopy. Ascribing to the hydrogel internal electrostatic interaction, hydrogen bond, and cation-π interaction, the obtained PZGs exhibited high ductility (>1200% strain) and appropriate strength (>189 kPa). Remarkably, PZGs could also adhere firmly on different substrates through noncovalent interaction, and their adhesion could be controlled by adjusting the amount of zwitterionic. Reversible physical interactions in polymer networks endowed hydrogels with excellent self-healing properties. In addition, PZGs exhibit good antibacterial activity and biocompatibility due to the synergistic effect of quaternary ammonium cation and amphozwitterion monomer. This work provides a multifunctional antibacterial coating for medical equipment and has broad application prospects in the biomedical field.


Assuntos
Compostos de Amônio , Hidrogéis , Hidrogéis/farmacologia , Hidrogéis/química , Antibacterianos/farmacologia , Antibacterianos/química , Polímeros , Cátions
4.
Biomater Sci ; 11(20): 6775-6780, 2023 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-37695067

RESUMO

The inherent migration behavior of bacteria has inevitably impacted the advancement of the antibacterial treatment technology. Hunting bacteria, especially those with flagellates, requires self-propelled materials, which could kill bacteria autonomously. Herein, we designed and synthesized a self-propelled micromotor (SPM) tailed with poly(thiazole) to yield bimetallic organic frameworks (BiOFs), in which the assembly of BiOFs are similar to the "Newman projection". The moving speed of the obtained SPM was 238.6 µm s-1 and presented excellent antibacterial activity; more than 90% bacteria were hunted and killed in flowing water. Its minimum inhibitory concentration (MIC) against E. coli and S. aureus was 3.2 and 0.4 mg mL-1, respectively, and its antibacterial activity was still retained after recycling for 5 times. Its antibacterial mechanism along with the contribution of the active units and flow rate was investigated. In summary, a novel self-propelled material for hunting bacteria was synthesized by an unprecedented and efficient strategy. This approach is anticipated to create huge possibilities for its applications in the fields of antibacterial, disinfection, and microdevices.

5.
Curr Microbiol ; 80(8): 243, 2023 Jun 13.
Artigo em Inglês | MEDLINE | ID: mdl-37382684

RESUMO

Notopterygium incisum Ting ex H. T. Chang (N. incisum) is a precious Chinese traditional medicine distributed in high-altitude regions of southwest China. The aim of this study was to investigate the composition, antibacterial activity, and cytotoxicity of essential oil from aerial parts of N. incisum. N. incisum essential oil (NI-EO) was extracted by hydro-distillation, and gas chromatography/mass spectrometry (GC-MS) analysis showed that the major components of NI-EO were D-limonene (18.42%) and γ-terpinene (15.03%). The antibacterial activity and mechanism study showed that the diameters of inhibition zone (DIZs) of NI-EO against E. coli and S. aureus were 14.63 and 11.25 mm and the minimum inhibitory concentrations were 3.75 and 7.5 µL/mL, respectively. NI-EO not only caused intracellular biomacromolecule leakage and cell deformation by destroying bacterial cell wall integrity and cell membrane permeability, but also degraded the mature biofilm. The low toxicity of NI-EO was demonstrated in an assay on bovine mammary epithelial cells. These results implied that NI-EO was mainly composed of monoterpenes and sesquiterpenes and had excellent antibacterial activity and showed low levels of cytotoxicity. It is expected to be applied as a natural antibacterial agent in the future.


Assuntos
Óleos Voláteis , Animais , Bovinos , Óleos Voláteis/farmacologia , Escherichia coli , Staphylococcus aureus , Antibacterianos/toxicidade , Componentes Aéreos da Planta
6.
Environ Sci Pollut Res Int ; 30(33): 80279-80292, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37296248

RESUMO

The environment and human health are in danger due to the long-term enrichment and buildup of organic pesticides, dyes, and harmful microbes in wastewater. The development of functional materials that are efficient for treating wastewater remains a significant problem. Eco-friendly hexagonal spindle-shaped Fe-MOFs (Hs-FeMOFs) were created in this study under the influence of cationic copolymer (PMSt). The mechanism of crystal growth and development of its unique morphology were described after looking into impact factors for the ideal circumstances and being characterized by XRD, TEM, XPS, and other techniques. It revealed that Hs-FeMOFs possess an enormous supply of adsorption active sites, a strong electropositivity, and the nanometer tip. Then, typical organic pollutants, such as herbicides and mixed dyes, as well as biological pollutants bacteria, were chosen to assess its efficacy in wastewater treatment. It was discovered that the pendimethalin could be quickly removed in wastewater and the removal rate reached 100% within 10 min. In separation of mixed dyes, the retention rate of malachite green (MG) reached 92.3% in 5 min and with a minimum inhibitory concentration of 0.8 mg/mL and demonstrated strong activity due to the presence of cationic copolymers. In actual water matrix, Hs-FeMOF could also play excellent adsorption and antibacterial activity. In summary, a novel, environmentally friendly MOF material with good activity was successfully created by cationic copolymer induction. It offers a fresh approach to develop functional materials in wastewater treatment.


Assuntos
Poluentes Ambientais , Poluentes Químicos da Água , Purificação da Água , Humanos , Águas Residuárias , Corantes/química , Purificação da Água/métodos , Polímeros , Adsorção , Poluentes Químicos da Água/química
7.
Life Sci ; 313: 121299, 2023 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-36535400

RESUMO

Streptococcus agalactiae is among the major causative pathogens of bovine mastitis, as well as crucial pathogen leading to human morbidity and mortality. Being a promising natural antibacterial agent, linalool has been broadly applied in medicine and food processing. However, its antibacterial effect against S. agalactiae has barely been elucidated. This study is the first to investigate the antibacterial activity and action mechanism of linalool against S. agalactiae causing bovine mastitis. Linalool exhibited significant antibacterial activity against S. agalactiae, with an inhibition zone diameter of 23 mm and a minimum inhibitory concentration of 1.875 µL/mL. In addition, linalool damaged cell structural integrity of S. agalactiae, leading to the leakage of intracellular components (alkaline phosphatase, nucleic acids and protein). Linalool also exhibited a scavenging effect on biofilm. Moreover, untargeted metabolomics analysis revealed that linalool stress substantially disrupted intracellular metabolism of S. agalactiae. Linalool caused energy metabolism disorder, and obstructed nucleic acid synthesis in S. agalactiae. Furthermore, downregulation of amino acids (e.g., proline, alanine) and upregulation of saturated fatty acids provide strong evidence for linalool induced cell wall and membrane damage. Overall, linalool exhibited strong antibacterial activity against S. agalactiae by destroying the cell structure and disrupting intracellular metabolism. This study provides a new insight and theoretical foundation for linalool application in preventing S. agalactiae infection.


Assuntos
Mastite Bovina , Streptococcus agalactiae , Animais , Bovinos , Feminino , Humanos , Streptococcus agalactiae/metabolismo , Mastite Bovina/tratamento farmacológico , Mastite Bovina/microbiologia , Antibacterianos/farmacologia , Antibacterianos/metabolismo
9.
Environ Sci Pollut Res Int ; 30(12): 32641-32654, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36469270

RESUMO

The environmental pollution with fluoride compounds was currently being paid more and more attention as it threatens the safety of animal and human life in an ecosystem. In this study, an eco-friendly adsorbing material for removing fluoride ion (F-) was prepared by hydroxyapatite nanowires (HAnWs), a typical biocompatible inorganic conjugates. UiO66, a typical zirconium-based metal-organic framework (MOF), was conjugated onto HAnW by a simple in situ hydrothermal reaction, which afforded a novel HAnW-based nanotwigs of conjugates like millet (UiO66@HAnWs). Being characterized by SEM, EDS, FT-IR, XRD, XPS, and TGA, the obtained UiO66@HAnWs were applied to removing F- in wastewater, and its adsorption capacity was optimized. It was found that UiO66@HAnWs had a bigger specific surface area (115.310 m2/g), and its efficiency for removing F- got to 99.3%, which was greatly improved than that of related materials. It was considered that the adsorption of F- on UiO66@HAnWs was mainly multi-molecular layer adsorption, which fluoride ions aggregate on the Zr(IV) active sites to attain ligand switching, and the nanoconjugated structure like nanotwigs of millet greatly improved its adsorption capacity. In summary, a novel eco-friendly UiO66@HAnWs with nanoconjugated structure could be constructed by simple hydrothermal method, which the agglomeration defects of MOFs were not only ameliorated, but also its adsorption capacity was greatly improved.


Assuntos
Fluoretos , Águas Residuárias , Animais , Humanos , Fluoretos/análise , Espectroscopia de Infravermelho com Transformada de Fourier , Ecossistema , Durapatita/química , Adsorção
10.
J Minim Invasive Gynecol ; 30(2): 156-163, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36410659

RESUMO

STUDY OBJECTIVE: To identify whether the use of a uterine manipulator (UM) or intracorporeal colpotomy conferred inferior short-term survival among patients treated for early-stage cervical cancer. DESIGN: Retrospective cohort study. SETTING: Tertiary university-based hospital. PATIENTS: 1169 patients with stage IB1 to IB2 cervical cancer. INTERVENTIONS: All patients underwent minimally invasive radical hysterectomy and pelvic lymphadenectomy. MEASUREMENTS AND MAIN RESULTS: A total of 1169 patients diagnosed with preoperative stage IB1 to IB2 cervical cancer were primarily treated with surgery from 2018 to 2019. The eligible patients had a median age of 48 years (range, 23-76 years), and the median follow-up time was 34 months (range, 3.57-50.87 months). The 2-year overall survival rate of the patients with pathologic stage IB1 and IB2 was 99.8% and 98.8%, respectively, according to the 2018 International Federation of Gynecology and Obstetrics staging system. Univariable analysis revealed that the UM group had a 7.6-times higher risk of death than that of the manipulator-free group (p = .006), but multivariable analysis clarified that only tumor size (p = .016; hazard ratio, 2.285; 95% confidence interval, 1.166-4.479) and parametrial involvement (p = .003; hazard ratio, 3.556; 95% confidence interval, 1.549-8.166) were independent risk factors for overall survival. There was no statistically significant difference in survival between patients who underwent intracorporeal and protective colpotomy. CONCLUSION: Short-term survival outcomes in women undergoing minimally invasive radical hysterectomy for treatment of early-stage cervical cancer did not differ when a UM was avoided or when a protective colpotomy was performed.


Assuntos
Neoplasias do Colo do Útero , Humanos , Feminino , Gravidez , Adulto Jovem , Adulto , Pessoa de Meia-Idade , Idoso , Neoplasias do Colo do Útero/patologia , Estudos Retrospectivos , Colpotomia , Estadiamento de Neoplasias , Prognóstico , Procedimentos Cirúrgicos Minimamente Invasivos , Histerectomia
11.
J Mater Chem B ; 10(44): 9202-9215, 2022 11 16.
Artigo em Inglês | MEDLINE | ID: mdl-36317705

RESUMO

As a novel antimicrobial material, quaternary phosphonium salts (QPSs) have been drawing close attention because of their excellent antimicrobial capacity with high activity and low bacterial survivability. Polymeric QPSs (PQPSs) also exhibit selectivity and long-term stability, however the polymerization of QPSs is severely challenged by low controllability and narrow selectivity of cation type. In this study, high-conversion RAFT polymerization is employed to prepare innovative phosphonium-functionalized diblock copolymers (PFDCs) with desired molecular weights and particle sizes. The excellent antibacterial activity of the PFDCs achieves lowest MIC values of 40 and 60 µg mL-1 (i.e., 1.4 and 2.2 µmol L-1) against E. coli and S. aureus, respectively. Mixing with an ink, dye, and latex coating does not weaken the antibacterial activity of the PFDCs, which inhibited 99.9% E. coli, showing broad applicability in different media. The effects of the cation type, synthesis medium, crosslinking content, and particle size on the morphology and antibacterial activity are studied. In summary, the RAFT polymerization of QPSs through the versatile design of ionic liquid monomers and the polymerization-induced self-assembly (PISA) method for constructing nano-assemblies with various micromorphology and particle size provides an exceedingly efficient way to build up multifunctional and multi-morphological polymeric nano-objects that open up vast possibilities in the fields of antibiotics, drug delivery, templated synthesis, and catalysis.


Assuntos
Escherichia coli , Staphylococcus aureus , Polímeros , Polimerização , Antibacterianos/farmacologia
12.
Gynecol Obstet Invest ; 87(6): 398-405, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36273460

RESUMO

OBJECTIVES: The objective of this study was to explore a better adjuvant treatment for patients with high-grade (HG) neuroendocrine cervical carcinomas (NECC) who had undergone surgery as a primary treatment. DESIGN: A retrospective cohort study, which involved women diagnosed as HG-NECC, was conducted in the Obstetrics and Gynecology Hospital of Fudan University. All patients had undergone radical surgery and pelvic lymphadenectomy with a laparotomy or a minimally invasive surgery. An analysis was made of the prognosis of HG-NECC. METHODS: Overall survival (OS) and progression-free survival (PFS) curves were drawn using the Kaplan-Meier method to be compared via log-rank tests. A Cox proportional hazards model was used to estimate the independent prognostic factors. RESULTS: A number of 110 patients diagnosed as HG-NECC at the pathological stage IA2 to IIIC2 according to the International Federation of Gynecology and Obstetrics (FIGO) 2018 staging system were initially treated with a primary surgery between 2008 and 2020. The eligible patients had the median age of 42.5 years (range: 22-76), with the median follow-up period of 39.6 months (range: 1.0-156.6). The 5-year OS of the patients at pathological stage I, II, and III accounted for 84.9%, 85.7%, and 60.9%, respectively. The Kaplan-Meier survival curves revealed no significant differences in OS and PFS between postoperative chemoradiotherapy and chemotherapy alone (OS: p = 0.77; PFS: p = 0.41). Etoposide plus platinum therapy did not improve OS when compared with platinum plus paclitaxel therapy after surgery (p = 0.71). The univariable analysis showed that chemotherapy with cycles ≥4 presented a better prognosis than with cycles <4 (OS: p = 0.01; HR = 6.71; PFS: p = 0.02; HR = 5.18). The multivariate analysis indicated that the cycles of chemotherapy (p = 0.02; HR 0.29) were a prognostic factor for PFS. LIMITATIONS: A retrospective design and the absence of partial follow-up data are limitations of the study. CONCLUSIONS: In initially surgically treated HG-NECC, postoperative chemotherapy alone showed no inferiority when compared with chemoradiotherapy for HG-NECC, and 4+ cycles of chemotherapy tended to produce a better prognosis than 4-ones.


Assuntos
Carcinoma Neuroendócrino , Neoplasias do Colo do Útero , Gravidez , Feminino , Humanos , Adulto Jovem , Adulto , Pessoa de Meia-Idade , Idoso , Colo do Útero/patologia , Estudos Retrospectivos , Estadiamento de Neoplasias , Platina/uso terapêutico , Histerectomia/métodos , Prognóstico , Carcinoma Neuroendócrino/tratamento farmacológico , Carcinoma Neuroendócrino/cirurgia , Neoplasias do Colo do Útero/tratamento farmacológico , Neoplasias do Colo do Útero/cirurgia , Quimioterapia Adjuvante
13.
Environ Sci Pollut Res Int ; 29(54): 82297-82308, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-35752672

RESUMO

In nowadays, environmental pollution has been greatly improved, but the development of low-cost and environmentally friendly materials are still challenge in the field of water treatment. Herein, a cheap and eco-friendly natural loess particle (LoP) was used for in situ growth of tungsten trioxide nanocubes (WO3NCs) on its surface via a simple one-pot hydrothermal method, which afforded a stable loess-based photocatalyst (WO3NCs@LoP). It was characterized by scanning electron microscopy (SEM), X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR) analysis, UV-Vis diffuse reflectance spectra (UV-Vis DRS), and X-ray photoelectron spectroscopy (XPS). The photocatalytic performances of WO3NCs@LoP were applied to photodegradation of organics under visible-light illumination. It was found that the removal rate of methylene blue (MB) got to 99% within 20 min, which was higher than that of materials, such as pure LoP and WO3NCs. Moreover, the photocatalytic activity of WO3NCs@LoP remained 85% after 9 cycling times, indicating its high stability and reusability. It was suggested that the synergy of the well narrowed band gap and effectual control of e--h+ recombination in WO3NCs@LoP improve its photodegradation efficiency. In summary, using natural minerals (LoP) as carrier, a novel eco-friendly photocatalyst could be explored for photodegradation of organic pollutions in wastewater treatment.


Assuntos
Luz Solar , Águas Residuárias , Águas Residuárias/química , Azul de Metileno/química , Espectroscopia de Infravermelho com Transformada de Fourier , Catálise
14.
Polymers (Basel) ; 14(7)2022 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-35406334

RESUMO

In the Loess Plateau region, the poor structure and properties of loess slopes will cause many types of geological disasters such as landslides, mudflow, land collapse, soil erosion, and ground cracking. In this paper, an eco-friendly polymer composite fertilizer (PCF) based on corn straw wastes (CS) and geopolymer synthesized from loess was studied. The characterization by FT-IR of the PCF confirmed that graft copolymer is formed, while morphological analysis by scanning electron microscopy and energy dispersive spectroscopy showed that geopolymer and urea were embedded in the polymer porous network. The effects of PCF contents on the compressive strength of loess were investigated. The PCF was characterized in terms of surface curing test, temperature and freeze-thaw aging property, water and wind erosion resistance, and remediation soil acidity and alkalinity property, which indicates that PCF can improve loess slope fixation and stability by physical and chemical effects. Moreover, the loess slope planting experiment showed that PCF can significantly increase the germination rate of vegetation from 31% to 68% and promote the survival rate of slope vegetation from 45.2% to 67.7% to enhance biological protection for loess slopes. The PCF meets the demands of building and roadbed slope protection and water-soil conservation in arid and semi-arid regions, which opens a new application field for multifunctional polymer composite fertilizers with low cost and environmental remediation.

15.
J Inorg Biochem ; 229: 111724, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-35093778

RESUMO

Antibacterial materials have been rapidly emerging as a primary component in the mitigation of bacterial pathogens, and green functional materials play a vital role in the antibacterial field. In this study, biocompatible hydroxyapatite nanowires (HANW) was used as a carrier, a coral rod-like nanowires hybrid of MoS2 and HANW (CR-MoS2@HANW) was synthesized via a facile two-step hydrothermal approach. After being characterized by scanning electron microscope (SEM), energy dispersive spectrometer (EDS), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), fourier transform infrared spectroscopy (FT-IR), Brunauer-Emmet-Teller (BET) and thermogravimetric (TG) analysis, the antibacterial activity and environmental compatibility were assessed. It was found that MoS2 nanosheets were in-situ assembled onto surface of HA nanowires, and the obtained nanohybrid exhibited excellent stability. CR-MoS2@HANW endowed a desirable long-term antibacterial activity against both gram-negative E. coli and gram-positive S. aureus. It was sufficient to inhibit the growth of bacteria within 72 h, and nanohybrids effectively promoted the growth of plants. In summary, the combination of MoS2 and HANW created a novel eco-friendly nanohybrids that could be applied as a promising multi-functional green antisepsis. And the CR-MoS2@HANW possessed enormous potential for biomedical applications.


Assuntos
Antibacterianos/farmacologia , Anti-Infecciosos Locais/farmacologia , Dissulfetos/farmacologia , Durapatita/farmacologia , Molibdênio/farmacologia , Nanofios/química , Antibacterianos/síntese química , Anti-Infecciosos Locais/síntese química , Dissulfetos/síntese química , Durapatita/síntese química , Escherichia coli/efeitos dos fármacos , Química Verde , Testes de Sensibilidade Microbiana , Staphylococcus aureus/efeitos dos fármacos
16.
J Environ Manage ; 299: 113636, 2021 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-34467862

RESUMO

BiOBr is a kind of promising photocatalyst because of excellent photoelectric separation efficiency and chemical stability. In order to improving practical application performance, a novel BiOBr ultra-thin nano-roundel (BiOBr-nR) was constructed in water-in-oil (WIO) emulsion microspheres, and prepared by hydrothermal reaction. Its specific surface area was increased by changing microtopography and downsizing. After being characterized by FT-IR, X-ray photoelectron spectroscopy (XPS), powder X-ray diffraction (XRD), scanning electron microscope (SEM), Brunauer-Emmett-Teller (BET), UV-Vis diffuse reflectance spectra (UV-Vis DRS) and photoluminescence (PL), it indicated the BiOBr-nR, being doped by C and N, is 4-5 times smaller and thinner than that of conventional BiOBr. It was also found that BiOBr-nR has narrower band gap energy (2.78 eV), excellent photocatalytic activity, significant reusability, and stability. The obtained BiOBr-nR photocatalysts were applied to remove organics. It presented excellent photocatalytic activity, the degradation rate of organics got to 99.2%. The mechanism of photodegradation was investigated, which indicated superoxide radicals and holes play a major role in the degradation of organics. Therefore, BiOBr-nR is a kind of environmentally friendly photocatalyst with stable photocatalytic activity, the removal rate still more than 97% after recycling for 10 times. In summary, we found a novel insight for designing and preparation of efficient and recyclable BiOBr photocatalytic materials, which exhibits high photoresponse for purifying the wastewater.


Assuntos
Bismuto , Catálise , Fotólise , Espectroscopia de Infravermelho com Transformada de Fourier
17.
Water Sci Technol ; 83(5): 1118-1129, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33724941

RESUMO

The attapulgite (APT), a typical nano-rod structured clay was introduced to MIL-101(Fe), a typical eco-friendly iron-based Metal-Organic Framework material (MOF), during the preparation by a one-step solvothermal method, which afforded a novel APT and MOF hybrid (APT@MIL). Based on the characterization of SEM, FT-IR and XRD, it was found that the rod-like crystals of APT determined the size of MIL-101(Fe) while maintaining its regular octahedral crystal form, and the crystal size of MIL-101(Fe) in APT@MIL enlarged 4 times. It was also discovered that the rod-like APT were evenly distributed in MIL-101(Fe) crystals. Using APT@MIL as the photocatalyst, some organic dyes were photodegraded in simulated sunlight. The analysis indicated that APT@MIL has high adsorption and photodegradation activity, the removal rate of methylene blue was up to 99.5%. Finally, the photocatalytic activity of APT@MIL was verified by UV-Vis DRS, photoluminescence spectra. The thermodynamic adsorption, kinetic characteristics adsorption, and removal mechanism of APT@MIL are also discussed. In summary, a novel hybrid material APT@MIL was successfully prepared with good adsorption and photocatalytic performance. It is expected to be used in photocatalytic degradation of dye wastewater.


Assuntos
Azul de Metileno , Dimaprit/análogos & derivados , Solventes , Espectroscopia de Infravermelho com Transformada de Fourier
18.
Int J Biol Macromol ; 174: 198-206, 2021 Mar 31.
Artigo em Inglês | MEDLINE | ID: mdl-33516853

RESUMO

The prevention and treatment of microorganism contamination on substrate surfaces have recently generated significant concern of scientists. In this paper, a novel diblock copolymer containing antibacterial quaternary ammonium groups as pendant groups, poly(3-(methacryloylamino) propyltrimethyl ammonium chloride)-b-poly(styrene) (PMS), was synthesized by interfacial polymerization. Also, PMS anisotropic particles (APs) could be successfully obtained based on different assembly behaviors by adjusting the ratios of monomers and the toluene/styrene (Tol/St). Moreover, silver loaded chitosan (Ag@CS) and PMS APs were combined to prepare natural/synthetic polymer antibacterial materials with dual-active centers (Ag@CS/PMS-4 APs), aiming to expand the application of carbohydrate polymers and improve the antibacterial activity of composite materials. Remarkably, the resulting series of PMS particles, especially worm-like PMS-4 APs, and Ag@CS/PMS-4 APs composite film ((Ag@CS/PMS-4 APs)-F) exhibited excellent antibacterial properties, which can be employed as interface materials to prevent the transmission of infectious diseases caused by microorganism contamination.


Assuntos
Quitosana/química , Compostos de Amônio Quaternário/química , Prata/química , Antibacterianos/síntese química , Antibacterianos/química , Anti-Infecciosos/síntese química , Anti-Infecciosos/química , Nanopartículas Metálicas/química , Polimerização , Polímeros/química , Compostos de Amônio Quaternário/síntese química
19.
Macromol Rapid Commun ; 41(23): e2000436, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33052626

RESUMO

One-pot transformation of monomer mixtures into block copolymers remains a key challenge. Herein, a metal-free route to prepare block copolymers from monomer mixtures by a hydroxyl functionalized ionic liquid of 3-(2-hydroxyl-ethyl)-1-methylimidazolium bromide (HEMIMB) is described. HEMIMB can bridge two catalytic cycles including ring-opening alternating copolymerization (ROAC) of phthalic anhydride (PA) with epoxides and ring-opening polymerization (ROP) of L-lactide (LA), and enable a selective copolymerization from PA, LA, and epoxides. The selective copolymerization depends on the presence of PA in mixed feedstocks, exhibits the first ROAC of PA with epoxides and then ROP of LA to the formation of block polyesters in one-pot strategy. This work is beneficial to the development of metal-free catalysts for sequence-controlled polymerization that enable block architectures from mixtures of monomers.


Assuntos
Líquidos Iônicos , Catálise , Poliésteres , Polimerização , Polímeros
20.
Nanoscale ; 12(42): 21940-21950, 2020 Nov 05.
Artigo em Inglês | MEDLINE | ID: mdl-33112328

RESUMO

Antibacterial materials are rapidly emerging as a primary component in the mitigation of bacterial pathogens, and functional polymers play a vital role in the preparation of antibacterial coatings. In this study, a novel antibacterial polymer with double active centers was synthesized. Firstly, using one-pot soap-free emulsion polymerization technology, the cationic acrylate copolymeric polyvidone (CACPV) was synthesized by copolymerization of four monomers with different functions, which were methyl methacrylate (MMA), N-vinyl-2-pyrrolidone (NVP), γ-methacryloxypropyltrimethoxysilane (MAPTS) and [3-(methacryloylamino)propyl]trimethylammonium chloride (MAPTAC). Secondly, using iodine complexation, the cationic acrylate copolyvidone-iodine (CACPVI) nanoparticles were prepared. After being characterized by scanning electron microscopy (SEM), dynamic light scattering (DLS), X-ray photoelectron spectroscopy (XPS) and contact angle test, the antibacterial activity of CACPVI was evaluated against the typical human pathogens Escherichia coli (E. coli, Gram-negative) and Staphylococcus aureus (S. aureus, Gram-positive). Additionally, CACPVI was used to improve the antibacterial activities of some materials, such as ink, dye and coatings. It was found that CACPVI presented an excellent antibacterial synergy. When the antibacterial activities were more than 99% at a concentration of 40.00 µg mL-1, CACPVI exhibited long-term antibacterial performance as expected. The antibacterial mechanism of this synergy was also investigated. In summary, a novel antibacterial polymer material with double active centers was successfully synthesized and was widely applied in coating, dye and ink materials for minimizing bacterial infection.


Assuntos
Iodo , Nanopartículas , Acrilatos , Antibacterianos/farmacologia , Escherichia coli , Humanos , Testes de Sensibilidade Microbiana , Staphylococcus aureus
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