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1.
A hierarchically Ag/nylon 6 tree-like nanofiber membrane (Ag/PA6 TLNM) was fabricated by adding tetrabutylammonium chloride (TBAC) and silver nitrate (AgNO3) into spinning solution via one-step electrospinning. TBAC presented in PA6/formic acid (HCOOH) spinning solution was able to cause the formation of a tree-like structure due to its space steric structure and the increasing of solution conductivity. Electrospinning solvent acted as a reducing agent for in situ conversion of AgNO3 into silver nanoparticles (Ag NPs) during the solution preparation. SEM, TEM, FT-IR XPS and XRD confirmed that Ag NPs were doped in the prepared nanofiber membrane successfully and the mechanical properties, pore size distribution and hydrophilicity of the membranes were investigated. The results showed that the tree-like structure improved the mechanical properties and hydrophilicity of the membrane while ensuring high specific surface area and small pore size. And the Ag/PA6 TLNM showed superior antibacterial properties against both E. coli and S. aureus compared with common Ag/PA6 nanofiber membranes (Ag/PA6 NMs). All of the results show that the Ag/PA6 TLNM would have potential applications in water purification.  相似文献   

2.
Polyglycolic acid-poly lactic glycolic acid (PGA-PLGA) electrospun nanofibers containing silver nanoparticles have been produced and twisted into the nanofibrous yarn. The morphology of nanofibers and produced yarns, as well as the mechanical properties of the yarns, were investigated. Furthermore, in vitro antibacterial properties and in vitro degradation behavior of yarns containing various silver nanoparticles were studied. SEM images confirmed that the addition of the silver nanoparticles into the polymer solution increases the fiber diameters. The result of the mechanical test of the yarns alone and used in two different forms of the knots was measured and results showed that the strength of the yarns without the knot was significantly more than that of others. The biodegradability test showed that the mechanical properties and the weight of the yarns were quickly reduced after subjecting to in vitro condition. The result of the antibacterial test indicated that the nanofiber yarns containing %3 silver nanoparticles were the most appropriate sample with a considerably antibacterial activity against both gram-positive bacterium Staphylococcus aureus and gram-negative bacterium Escherichia Coli with inhibition zones of 8.1 and 9.5 mm, respectively; which demonstrated that silver nanoparticles retained their effectiveness after the electrospinning process. Therefore the nanofibrous yarns containing silver nanoparticles could be successfully produced by the electrospinning process with the proper antibacterial property as a candidate for the surgical sutures.  相似文献   

3.
GSP/gelatin composite nanofiber membranes containing silver nanoparticles were successfully fabricated as a novel biomaterial by electrospinning. The silver nanoparticles (AgNPs) were synthesized with the grape seed polyphenols (GSP) as reducing agent in aqueous solution of gelatin, and then the GSP/gelatin/AgNPs mixed solution was electrospun into nanofibers at 55 °C. The scanning electron microscopy (SEM) confirmed that the composite fibers were uniform and the average fiber diameter ranged between 150 nm and 230 nm with an increase in applied potentials from 14 kV to 22 kV. And the transmission electron microscopy (TEM) showed that silver nanoparticles distributed individually in the fibers with the average particle size of about 11 nm. Furthermore, the ultraviolet visible spectrophotometer (UV-vis spectroscopy) test demonstrated that all of Ag+ converted to Ag0 when the concentration of gelatin was 24 wt% and the mass ratio of GSP to AgNO3 was about 5:2. The antibacterial activities of the fiber membranes against E.coli and S.aureus were measured via a shake flank test and demonstrated good performance after the importation of silver nanopaticles. Cytotoxicity testing also revealed that fiber membranes contained silver nanoparticles had no cyto-toxic. All the results indicated that the GSP was effective for the formation and stabilization of silver nanoparticles in composite nanofibers mats which had the potential for applications in antimicrobial tissue engineering and wound dressing.  相似文献   

4.
Dry bacterial cellulose nanofiber (BC) sheet coated with poly(lactic acid) (PLA) was developed and characterized towards acute wound healing applications. This new approach of PLA coating on BC revealed enhanced physical and antibacterial properties. Commercial BC sheets originated from the manufacturing of nata de coco jelly were dried and coated with the PLA at various concentrations of 2, 4, 6, 8, 10 and 12 % w/v for the purpose of improving the mechanical properties and followed by loading of antiseptic such as benzalkonium chloride (BAC). PLA has been proposed for the use of coating materials at a concentration of 8 %, the biocomposite sheet started exhibiting a low moisture uptake, prolonged swelling in simulated wound fluid solution and high tear (9.17 Nm2/kg) and burst indices (32.5 kPa·m2/g). The 8 % PLA coating revealed porous fiber-like morphology as observed under scanning electron microscope. Therapeutic loading capacity of the BC/8 PLA was substantially higher than the pristine BC. Furthermore strong antimicrobial activities against Staphylococcus aureaus and Escherichia coli were observed for the BC/8PLA biocomposite film. These reports were clearly suggestive of the fact that synthetic biodegradable polymers, such as PLA, may be exploited for the synergistic combination with BC for antimicrobial and acute wound management. This new and modified fiber source material could reduce the dependency on plant based cellulose for more demanding biomedical applications such as wound healing materials, vascular graft, cartilage replacement, drug delivery and tissue engineering.  相似文献   

5.
The present investigation describes the synthesis and characterization of novel biodegradable nanoparticles based on chitosan for biomedical applications. The presence of primary amine groups in repeating units of chitosan grants it several properties like antibacterial activity, antitumor activity and so on. Chitosan forms nanoparticles spontaneously on the addition of polyanion tripolyphosphate which has greater antimicrobial activity than parent chitosan. In the present study, chitosan nanoparticles (ChNP) were prepared by the ionic gelation method. The physiochemical characteristics of nanoparticles were analyzed using XRD, SEM, FTIR. The antibacterial activity of chitosan nanoparticles against medical pathogens Klebsiella pneumoniae, Escherichia coli, Staphylococcus aureus and Pseudomonas aeruginosa was evaluated by calculation of minimum inhibitory concentration (MIC) and compared with chitosan and chitin activity. The mode of action and factors affecting antibacterial activity were also analyzed. ChNP compounds exhibited superior antimicrobial activity against all microorganisms in comparison with chitosan and chitin. The antibiofilm activity was studied using crystal violet assay and growth on congo red agar. The study is thus a good demonstration of the applicability of chitosan nanoparticles as an effective antimicrobial agent with antibiofilm activity as well.  相似文献   

6.
Synthesis of biocompatible polymer nanofibers is valuable, due to their use as a cover for burns and as a replacement for bandage because of their antimicrobial properties. In this study, electrospinning of chitosan(Ch) and nanofibers synthesis with antibacterial properties was investigated. Nanofibers with antibacterial properties were synthesized by electrospun of Ch/poly(L-lactide)(PLA)/Imipenem(Imi) polymer solution. The results showed that the optimized ratio of Ch/PLA polymer solution was ratio of 50:50 and Ch 2 wt% and PLA 10 wt% polymer solution was the best weight percentage for nanofiber preparation. Also, the average diameter of Ch/PLA/Imi nanofibers was 143 nm and measured with ImageJ software. Afterwards, the antibacterial properties of Imi as additives (with different percentages) was studied in the polymer solution. The scanning electron microscopy (SEM) images and antibacterial tests were showed that the electrospun of Ch/PLA/Imi polymeric nanofibers were effective against Gram negative bacteria Escherichia coli (E. coli) and inhibited growth of E. coli. The growth and viability percentage of fibroblast cells with nanofibers in αMEM culture are at desirable levels after 6 days.  相似文献   

7.
In this study, two biodegradable polymers, polycaprolactone (PCL) and polyvinyl alcohol (PVA) were used to fabricate nanofiber nonwovens (NFNs). Also, the silver nanoparticles (AgNPs) successfully reduced by using tea polyphenols (TP) and incorporated in the NFNs via electrospinning. The morphologies of the NFNs and AgNPs were analyzed by scanning electron microscopy (SEM), transmission electron microscopy (TEM), respectively. The PCL nanofibers and PVA nanofibers interweaved each other, and AgNPs with average diameter 1.53±0.15 nm were embedded in the PVA nanofibers. The properties of electrospun NFNs were characterized by pore property, swelling/weight loss, water contact angle, mechanical property, and antibacterial activity. The nanofibers cross-linked to each other forming the 3Dnetwork porous structure with diameter about 1-1.5 μm. Although the hydrophobic PCL was added in the hybrid NFNs, the NFNs still showed hydrophilic propriety, high swelling degree (i.e. swelling degree is 330 % for 48 h), and low weight loss (i.e. weight loss is 22.4 % for 48 h). Also, the hybrid PCL/PVA/AgNPs NFNs exhibited a suitable mechanical property for wound dressings (i.e. tensile strength is 4.27 MPa, and breaking elongation is 88 %). Moreover, the hybrid NFNs effectively inhibited growth of Escherichia coli and Staphylococcus aureus. In summary, this PCL/PVA/AgNPs NFNs may provide a promising candidate for accelerating wound healing.  相似文献   

8.
We present a rapid, simple, convenient and cost-effective method for producing nanosized stable silver particles on cotton fibers with complete control of the silver loading level using a thermal reducing silver carbamate complex. Cotton gauze was coated with silver 2-ethylhexylcarbamate solution. Silver nanoparticles on the cotton gauze were characterized by energy dispersive X-ray spectroscopy and X-ray diffraction. Particle size and lattice image of the silver nanoparticles were studied by scanning electron microscopy. The antibacterial activity of the silver coated cotton gauze against Escherichia coli and Staphylococcus aureus, whole blood clotting and physical properties including vertical wicking test, water retention time and absorption of 0.9 % (w/v) saline were studied. Silver coated cotton gauze showed a faster blood clotting rate than the untreated cotton gauze. Cotton gauzes treated with two different silver concentrations (0.01 %, 0.1 %) showed slightly better saline absorption and they had better vertical wicking and water retention time than pristine cotton gauze.  相似文献   

9.
In this study silver nanoparticles with different particle sizes and hence colors were synthesized on silk and cotton fabrics through reduction of silver nitrate. Particle sizes of the silver colloids were measured by dynamic light scattering (DLS). The structure and properties of the treated fabrics were characterized by scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDS), X-ray diffraction (XRD), and UV-Vis reflectance spectroscopy. Various characteristics of the treated fabrics including antibacterial activities against a Gram positive (Staphylococcus aureus) and a Gram negative (Escherichia coli) bacteria, color effect, wash and light fastness, water absorption, fabric rigidity, and UV blocking properties were also assessed. The results indicated that the treated fabrics displayed different colors in the presence of silver nanoparticles with different particle sizes and exhibited good and durable fastness properties. Also, the size of the silver particles had a tangible effect on antibacterial activity of treated fabrics and its antibacterial performance was improved by decreasing the size of particles. Moreover, this process imparted significantly UV blocking activity to fabric samples.  相似文献   

10.
In order to prevent surgical complications due to microbial infections, we have developed polypropylene suture grafted with silver nanoparticles (PPsuture/Ag nanocomposite) by a simple immersion procedure. Physical and mechanical properties of developed suture are investigated. Suture surface characteristics are examined by scanning electron microscopy (SEM) imaging and atomic force microscopy (AFM). Silver content on suture surface was determined by Inductively coupled plasma atomic emission spectroscopy (ICP-AES). The mechanical properties of developed antibacterial PP suture/Ag were studied. We note that proposed silver coating method has not affected mechanical performances of suture. Antimicrobial performances of PP suture/Ag nanocomposites against S. aureus and E. coli colonies were also investigated.  相似文献   

11.
Pre-loading of monochlorotriazinyl β-Cyclodextrin (MCT-βCD) onto/within viscose/wool (V/W) and cotton/wool (C/W) blended fabrics provide hosting cavities that can form host-guest inclusion complexes with reactive dyes in postprinting as well as with triclosan derivative or silver nanoparticles/hyperbranched polyamide-amine (AgNPs/HBPAA) composite in subsequent final antibacterial finishing step. Coloration properties, antibacterial activity against (S. aureus) and (E. coli) pathogenic bacteria, durability of the obtained products, according to the above mentioned route, to wash, surface morphology and composition of selected samples were investigated. Results obtained signify that premodification of the nominated substrates with MCT-βCD (10 g/l), followed by reactive printing with mono-or bifunctional reactive dye (20 g/l), and subsequent post-finishing with triclosan derivative or AgNPs/HBPAA composite (15 g/l each) is an efficient treatments sequence for attaining reactive prints with significant antibacterial efficacy and noticeable durability to wash. Surface depositions of selected active ingredients were also confirmed using SEM and EDX analysis.  相似文献   

12.
In order to prepare antimicrobial regenerated cellulose fibers from blended spinning solutions, three non-water soluble polymeric guanidine derivatives, polyhexamethylene guanidine dodecyl benzene sulfonate (PHGDBS), polyhexamethylene guanidine dodecyl sulfate (PHGDSA), and polyhexamethylene guanidine laurylsulfonate (PHGLSO) were synthesized. And the chemical structure of these agents was verified by element analysis, Fourier transform infrared spectroscopy (FTIR), and proton nuclear magnetic resonance (1H-NMR). The antimicrobial activity of the three agents as well as cellulose films containing PHGDBS was also studied. The results showed that the compounds we prepared had strong properties against both bacterial and fungus, including Staphylococcus aureus (S. aureus), Escherichia coli (E. coli), Candida albicans, and Aspergillus niger. Moreover, it was found that three antimicrobial agents were insoluble in water but they can dissolve in solvents of cellulose such as 1-butyl-3-methylimidazolium chloride ([BMIM]Cl) and N-methylmorpholine-N-oxide monohydrate (NMMO·H2O). Meanwhile, it was also proved that [BMIM]Cl had little effect on the antimicrobial properties of these agents. The cellulose films containing only 1.0 wt% PHGDBS showed 99.94 % and 96.95 % bacterial reduction rates for S. aureus and E. coli, respectively. Moreover, still over 91 % of bacterial reduction was maintained after 15 laundering cycles. It suggests that the three agents will be suitable to prepare antimicrobial regenerated cellulose fibers or films.  相似文献   

13.
With the increased risk of disease transmissions and cross-infection caused by microorganisms, the control of microbial infections becomes a very important issue in modern societies. Moreover, with the emergence of antibio-resistant bacterial strains, it is necessary to control the bacterial growth. One of ways to limit the bacterial proliferation is to develop antimicrobial surfaces. The present work describes the synthesis process of a direct linking of propargyled Triclosan to a modified Kraft Pulp. Propargylated Triclosan, and azidated Kraft Pulp were linked in the presence of Cu(I) catalyst, a type of Huisgen’s 1,3-dipolar azide-alkyne cycloaddition reaction, leading to the formation of Triclosan linked to kraft Pulp fibers. The modified Kraft Pulp fibers are characterized by Fourier transform infrared spectroscopy (FTIR) and X-ray photoelectron spectroscopy (XPS). This novel material has been investigated for its antibacterial properties against Escherichia coli, Staphylococcus aureus, Bacillus cereus and Pseudomonas aeruginosa. The developed material showed an important antibacterial activity. Although Triclosan is covalently grafted onto Kraft Pulp, its antibacterial properties are maintained.  相似文献   

14.
The aim of this study was to investigate the bioactivity of the essential oil isolated from Origanum vulgare L. (EOv). We analyzed the in vivo anti-inflammatory properties in a mouse-airway inflammation model and the in vitro antimicrobial activity, genotoxicity over the anaphase-telophase with the Allium cepa strain and its cytotoxicity/viability in A549 culture cells. In vivo, EOv modified the levels of tumor necrosis factor -α and viable activated macrophages and was capable to mitigate the effects of degradation of conjugated dienes. In vitro, EOv reduced the viability of cultured A549 cells as well as the mitotic index and a number of chromosomal aberrations; however, it did not change the number of phases. We found that EOv presents antimicrobial activity against different Gram (?) and (+) strains, measured by disc-diffusion test and confirmed with a more accurate method, the AutoCad software. We postulate that EOv presents antibacterial, antioxidant and chemopreventive properties and could be play an important role as bioprotector agent.  相似文献   

15.
Fruits obtained from shrubs of the Crataegus elbursensis (C. elbursensis) plant demonstrate significant antioxidant and antibacterial properties. In this study, natural dye was sono-extracted from fresh and dried fruits and applied in dyeing and antibacterial finishing of wool. The maximum sono-extraction yield was obtained when optimal conditions of ethanol/ water (4/1 v/v) as extracting solvent, time 30 min, pH 4, temperature 50 oC, and C. elbursensis concentration 10 g/l were used. When wool yarns were dyed with the extracted natural dye, the maximum dye uptake was achieved using dye concentration 75 % owf, and dyeing condition of 100 oC, 60 min, pH 4, and LR 100:1. Different metal salts like aluminum sulfate, copper sulfate, and tin chloride were applied on wool by pre-mordanting method and their effects on dye uptake, color variation, and color fastness were examined. Results showed that the natural dye itself had relatively high uptake and good color fastness on un-mordanted wool. Further, each mordant had different effect on dye uptake, color variation, and color fastness properties depending on its coordination ability with dye molecules and wool chains. Moreover, dyed yarns showed good antibacterial activity against Escherichia coli (E. coli) and Staphylococcus aureus (S. aureus) bacteria.  相似文献   

16.
This study aimed to produce poly(4-vinyl pyridine) and hydroxypropyl methacrylamide (HPMA)-based bilayer wound dressings materials enhancing healing mechanism for the wounds which have self-healing problem and high infection risk. These materials were designed to protect wound from secondary traumas caused microorganism invasion and do not have toxic substance release problem. Synthesis of quaternary poly(4-vinyl pyridine) (poly(Q4-VP)) which is the antibacterial layer of wound dressing material was carried out in two stages. At first stage, poly(4-vinyl pyridine) polymer was synthesized from 4-vinyl pyridine monomer by free radical polymerization. Then, poly(Q4-VP) was synthesized from poly(4-VP) by alkylation reaction with 6-bromocaproic acid. Resulted polymer was structurally characterized by FT-IR. The macroporous spongy structure, as the lower layer of wound dressing material, was prepared by cryogelation of HPMA. Then, the antibacterial polymer was electrospun onto the cryogel structure and bilayered material was obtained. Cryogel structure, fiber morphology and layer integration was examined by SEM. In order to enhance wound healing process, ascorbic acid (vitamin C) was loaded to cryogel layer and release was followed by spectrophotometrically. The antimicrobial properties of the materials were examined against Escherichia coli, Staphylococcus aureus and Candida albicans, respectively. According to the results, bilayered, antibacterial and antifungal against Staphylococcus aureus and Candida albicans, temporary wound dressings which can stimulate wound healing and have high swelling capacity were obtained successfully.  相似文献   

17.
The nanofiber membrane prepared by electrospinning has been widely applied in lithium-ion batteries. A powerful strategy for designing, fabricating and evaluating Poly-m-phenylene isophthalamide (PMIA) nanofiber membrane with SiO2 nanoparticles was developed by electrospinning in this paper. The morphology, crystallinity, thermal shrinkage, porosity and electrolyte uptake, and electrochemical performance of the SiO2/PMIA nanofiber membranes were investigated. It was demonstrated that the nanofiber membrane with 6 wt% SiO2 possessed notable properties, such as better thermal stability, higher porosity and electrolyte uptake, resulting in higher ionic conductivity (3.23×10-3 S·cm-1) when compared with pure PMIA nanofiber membrane. Significantly, the SiO2/PMIA nanofiber membrane based Li/LiCoO2 cell exhibited more excellent cycling stability with capacity retention of 95 % after 50 cycles. The results indicated that the SiO2-doped PMIA nanofiber membranes had a potential application as separator in high temperature resistance lithium-ion batteries.  相似文献   

18.
The efficacy of antimicrobial treatment of cotton fabrics depends on various parameters of the coating process, such as the chemical nature and concentration of the antimicrobial agent, the composition of the crosslinking formulation, and the curing temperature. The inclusion complex of triclosan with β-cyclodextrin (βCD) was synthesized and characterized by FTIR, XRD, NMR, Raman, SEM, and TGA. The minimum inhibitory concentration and minimum bactericidal concentration of the complex against Klebsiella pneumoniae and Staphylococcus aureus were compared to those of its precursor. A multifactorial study included an evaluation of the effects of triclosan complexation with β-cyclodextrin, a comparison between the glyoxal and tetracarboxylic acid as crosslinkers, an investigation of the effect of crosslinker and catalyst concentrations, and a comparison of curing at 120°C and 180°C. The cotton was characterized by FTIR-ATR, the micrographs of treated samples were obtained by SEM and the weight add-on was calculated. The bactericidal properties were determined according to AATCC-147. The correlation between the coating process parameters and the antimicrobial efficacy was determined. The optimal combination leading to the highest weight add-on and the antimicrobial coating that was most durable to multiple detergent washes at an elevated temperature was the use of complexed triclosan grafted onto the cotton in the presence of tetracarboxylic acid, followed by curing at 180°C. The curing temperatures were 120°C (P=0.002) and 180°C (P=0.008), catalysts were 1 % and 2 % aluminium sulfate and sodium hypophosphite (P<0.001), and the crosslinkers were 5 % and 10 % glyoxal and butanetetracarboxylic acid (P<0.001); these parameters significantly enhanced the antimicrobial properties of the treated fabrics. The study showed that βCD did not have antimicrobial activity, while the βCD/triclosan-treated textile exhibited potential antimicrobial properties. Overall, the bactericidal activity of fabrics can be enhanced by using βCD/triclosan with 10 % butanetetracarboxylic acid as a cross-linker and 5 % sodium hypophosphite as a catalyst at a curing temperature of 180°C.  相似文献   

19.
The present study has been focused on the extraction of natural dyes from Syzygium cumini (L.) Jambolan fruit dry seed endosperm and investigation of their phytochemicals and pharmacological characteristics. Dyes were prepared using aqueous, acidic, alcoholic and alkaline extraction techniques. UV spectral studies of the dyes showed a variation in absorption maxima and their color varied with respect to the pH and the solvent used during extraction. The dye was prepared from Jambolan fruit dry seed endosperm showed good antibacterial activity. The aqueous extraction of Jambolan fruit dry seed endosperm was able to inhibit the growth of many bacterial strains viz S. lutea, E.coli, P. aeruginosa, Pseudomonas fluorescens and S. aureus etc. The antimicrobial property of the dyes was used in developing antimicrobial fabric.  相似文献   

20.
Phthorimaea operculella (Zeller) is one of the most common insect pests of cultivated potato in tropical and subtropical regions. In this research, a potential strategy to improve the insecticidal activity of plant essential oils for the effective management of P. operculella was studied. The insecticidal and residual effects of nanofiber oil (NFO) and pure essential oil (PEO) of Cinnamomum zeylanicum were assessed on PTM under laboratory conditions. The nanofibers were made by the electrospinning method using polyvinyl alcohol (PVA) polymer. The morphological characteristics of the nanofibers were evaluated by scanning electron microscopy and Fourier transform infrared spectroscopy. The chemical constituents of cinnamon essential oil (EO) were detected by GC/MS. Fumigant toxicity of NFO and PEO were evaluated on different growth stages (egg, male and female adults) of P. operculella. SEM and FTIR analyses confirmed the presence of EO on the nanofiber structure. The yield of the EO from C. zelanicum on the nanofibers was 1.86%. GC/MS analysis showed that cinnamaldehyde was the primary constituent (69.88%) of cinnamon EO. LC50 values of C. zelanicum EO and NFO were 4.92 and 1.76 μl/l air for eggs, 0.444 and 0.212 μl/l air for female adults, and 0.424 and 0.192 μl/l air for male adults, respectively. Fumigant bioassays revealed that NFO was more toxic than C. zeylanicum oil against at all stages of P. operculella. The residual effect of PEO and NFO was evaluated against the egg stage of the P. operculella. NFO lost insecticidal effectiveness 47 days after application, while the efficacy of PEO decreased 15 days after application. Our results suggest that NFO of C. zeylanicum can be used as an effective new tool for the management of P. operculella.  相似文献   

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