CHEMOSPHERE
·
2021
·
IF 7.086
Yi Zhao,Meixia Fan,Wenlin Zhou,Yanwei Li,Yan Wang,Zongming Xiu,Baoyu Gao
Sludge generated in wastewater treatment facilities is an integral part for the introduction of silver nanoparticles (AgNPs) to the terrestrial environment, which would cause some adverse ecosystem responses. The understanding of silver release process from the sludge is important to evaluate their risks. In this study, the amount and speciation of the released silver were investigated by taking the sludge generated by wastewater coagulation with AgNPs added (denoted as sludge C-AgNPs ) an example, and kinetic analysis and density functional theory (DFT) calculations were first used to explore the controlling steps and pathways about the silver release. The results showed that sludge C-AgNPs could release the dissolved silver and the colloidal silver. Beside Cl − , Ca 2+ in the leaching solution could enhance the silver release of sludge C-AgNPs , especially for the colloidal silver. The released colloidal silver restricted in size from 40 nm to 100 nm with irregular shape. Although the oxidative dissolution of Ag 0 was the origin of the silver release pathways from the sludge C-AgNPs , the silver diffusion was the controlling step due to the spontaneous binding between silver and the hydrolysates of polyaluminium chloride in sludge C-AgNPs . However, Ca 2+ in the leaching solution could occupy the binding site of silver on sludge C-AgNPs , which would increase the diffusion rate of silver over the oxidative rate of Ag 0 . With this condition, the controlling step of silver release from sludge C-AgNPs turned to the oxidative dissolution of Ag 0 . Our findings are important to assess the fate of AgNPs in wastewater treatment as well as sludge applications.
研究领域:
环境科学
·
化学
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DOI
PubMed
高影响因子
BIOMACROMOLECULES
·
2021
·
IF 6.988
Wenshi Xu,Yong Chen,Bing Zhang,Wenwen Xu,Jie Niu,Yu Liu
Supramolecular assembly loading drug as biomedical materials is a research hotspot. Herein, we reported a supramolecular electrospun assembly constructed via the hydrophobic and hydrogen bonding interaction. The obtained results showed that the assembly by supramolecular electrospinning not only increased the interactions of multiple antibacterial active species including antibiotics, cationic polymers, and silver to form a flexible membrane with good mechanical strength but also indicated the dual effects of rapid doxycycline and polyethyleneimine release as well as a sustained Ag release. Interestingly, the assembly showed not only good degradability but also a high bacteriostatic efficacy toward Escherichia coli (E. coli) up to 99.9%. More importantly, the in vivo wound healing assay indicated that the assembly could promote the healing of uninfected, E. coli-infected, and even methicillin-resistant staphylococcus aureus-infected wounds. The current research provides a novel approach to construct a supramolecular assembly by electrospinning mechanically induced strong noncovalent interaction.
研究领域:
生物材料学
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药剂学
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微生物学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Materials Science & Engineering C-Materials for Biological Applications
·
2020
·
IF 5.88
Huaxin Lv,Sisi Cui,Qianwen Yang,Xiaoyu Song,Duo Wang,Junli Hu,Yifa Zhou,Yichun Liu
Silver nanoparticles (AgNPs) have a wide antimicrobial spectrum and low incidence of resistance. They have been widely incorporated into wound dressings for antimicrobial purpose. However, these wound dressings suffer from the accompanied cytotoxicity. It is important but challenging for them to reduce the cytotoxicity without compromising antimicrobial activity, while the affecting factors are unknown. In this work, we incorporated AgNPs into starch nanofiber mats with the in situ reduction method, and investigated the structure and property of the composite nanofiber mats in detail. We found that the cytotoxicity and antibacterial activity of the starch/AgNPs composite nanofiber mats are both affected by the release behavior of silver from the mats, while of various stages and governing factors. The cytotoxicity of the mats depends on the silver release rate at the early stage, which is governed by both the size and content of the AgNPs. The antibacterial activity is more related to the silver release rate at the later stage and is determined mainly by the content of AgNPs. By optimizing the size and content of AgNPs, we found a safe window and obtained starch/AgNPs composite nanofiber mats with good antibacterial activity and excellent cytocompatibility as well. The composite nanofiber mats also showed moderate wet strength (1–2 MPa), high liquid absorption capability (19–34 times of their own weights) and suitable vapor permeability [0.22–0.26 g/(cm 2 ·24 h)]. These starch/AgNPs composite nanofiber mats are ideal candidates for the treatment of infected and exuding wounds.
研究领域:
材料科学
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生物学
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医学
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产品关联
DOI
PubMed
高影响因子
INTERNATIONAL JOURNAL OF BIOLOGICAL MACROMOLECULES
·
2023
·
IF 8.2
Mingqi Xu,Huayong Luo,Hongwei Rong,Shuhan Wu,Zexin Zheng,Boyuan Chen
This paper reports the preparation of calcium alginate gels-functionalized PUF decorated with AgNPs (CA/PUF@Ag) by in situ reduction of Ag + ions to form AgNPs with weakly reducing glycerol in CA/PUF composite. The water-adsorbing capacity, chemical structure, crystalline nature, elemental composition and morphologies of the composite were characterized. The Ag release behavior of CA/PUF@Ag was investigated. The inhibition zone test, time-dependent co-culture assay, test tube test, and antibacterial filtration experiment with Escherichia coli as an indicator of bacterial contamination were conducted to explore the antimicrobial efficacy. Results indicated that the CA/PUF@Ag prepared at 0.25 % w / v of SA could absorb more water with a higher swelling ratio of 8.0 g/g than that of PUF@Ag (6.0 g/g), which was subsequently squeezed by minimal pressure stimuli. The CA/PUF@Ag had a larger initial AgNPs loading amount (8.48 mg/g), lower Ag release concentration (44.35 μg/L) and lower Ag release rate (0.27 %) after 14 days tests than those of PUF@Ag (7.93 mg/g, 80.87 μg/L and 0.60 % respectively). The CA/PUF@Ag was highly reusable because bacterial cells in the squeezed water recovered from the composite were completely inactivated over five cycles of operation, and exhibited good antibacterial efficacy as an antibacterial filter in a flow test.
研究领域:
材料科学
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环境工程
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纳米技术
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微生物学
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产品关联
DOI
PubMed
高影响因子
Journal of Coatings Technology and Research
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2018
·Vol. 15
·期 3
·593-602
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IF 1.619
Li Lin,Wang Yunli,Zhu Yingchun
Metallocene polyethylene/nano-silver coatings were prepared by a facile air-spray method on polymer films. Different from the prevailing strategy to endow polyethylene with antibacterial performance, we used metallocene polyethylene sol and nano-silver as a precursor to deposit coatings on polymers at a relatively low operating temperature. Antibacterial coatings with excellent mechanical properties, water resistance, and low silver release were achieved. The composite coatings were examined in terms of surface characteristics, mechanical properties, and antibacterial activity against two representative bacterial strains including Escherichia coli ( E. coli ) and Staphylococcus aureus ( S. aureus ). The composite coatings exhibited favorable microstructure, good mechanical properties, and suitable crystallinity. The antimicrobial tests indicated that the fabricated composite coatings showed promising antibacterial activity against E. coli and S. aureus . Furthermore, Ag ions released by the composite coating after 30 days were under 1.2 ppb. These results indicated a promising prospect of the composite coating for wide antibacterial applications.
研究领域:
材料科学
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高分子科学
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纳米技术
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生物医学工程
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产品关联
DOI
高影响因子
EUROPEAN POLYMER JOURNAL
·
2023
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IF 6
Yongwei Cai,Hong Yang,Jianxiang Li,Ronghua Gu,Yuhang Dong,Qi Zhao,Yao Chen,Yuanju Li,Ruru Wang
Catheter-associated urinary tract infections (CAUTI) account for 40% of all hospital-acquired infections and more than 1 million CAUTIs occur annually in the United States and Europe with increased morbidity and mortality. Although anti-bacterial coating is an effective way to solve this problem, so far only limitted progress has been made. In this paper we prepared a novel antibacterial silver nanoparticles poly(acrylamide)-chitosan-polyvinylpyrrolidone (AgNPs-PAAm-CS-PVP) composite hydrogel coating on latex urinary catheters by a simple dipping method. The average particle size, the size distribution as well as the polydispersity index (PDI) value of the AgNPs were examined by using TEM analysis. The surface morphology and roughness, the element contents, the functional groups, the static contact angles, and the surface energy of the coatings were characterized by using SEM, EDS, AFM, FTIR, XPS, and a video optical contact angle instrument, respectively. The amount of the total Ag released from the hydrogel was tested by ICP-MS. The antibacterial and antiadhesion efficacies against Gram-negative E. coli of the coated urinary catheters were evaluated with an inhibition zone test and fluorescence microscopy. A synergistic antibacterial mechanism of AgNPs and CS was also presented. The results showed that the synthesized AgNPs in the hydrogel had a spherical shape with an average diameter of 25.9 nm. The AgNPs-PAAm-CS-PVP hydrogel had a more durable release of the antibacterial agents of AgNPs and Ag + , which explains why the coated urinary catheters had long-term antibacterial activity. The mathematical modelling of Ag release kinetics supported Case I or Fickian diffusion mechanism for the AgNPs-PAAm-CS-PVP hydrogel. The hydrogel-coated urinary catheters became smoother and more hydrophilic which further explains why the coated urinary catheter decreased bacterial adhesion. More importantly, bacterial activity and bacterial adhesion assays showed that both the outer and inner surfaces of the AgNPs-PAAm-CS-PVP hydrogel-coated urinary catheters had strong antibacterial property against E. coli . Furthermore, the hydrogel-coated urinary catheters showed high hemocompatibility and cytocompatibility for promising biomedical applications. The AgNPs-PAAm-CS-PVP hydrogel-coated urinary catheters have great potential for decreasing CAUTIs.
研究领域:
材料科学
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生物材料
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生物医学工程
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传染病学
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纳米技术
✓ 已验证
产品关联
DOI
高影响因子
危险品化学品经营许可证（带存储）