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Polymers
Due to the pressing problems of today’s world, regarding both the finding of new, environmentally friendly materials which have the potential to replace classic ones, and the need to limit the accelerated spread of bacteria in hospitals, offices and other types of spaces, many researchers have chosen to develop their work in this field. Thus, biopolymeric materials have evolved so much that they are gradually becoming able to remove fossil-based plastics from major industries, which are harmful to the environment and implicitly to human health. The biopolymer employed in the present study, Arboblend V2 Nature with silver nanoparticle content (AgNP) meets both aspects mentioned above. The main purpose of the paper is to replace several parts and products in operation which exhibit antibacterial action, preventing the colonization and proliferation of bacteria (Streptococcus pyogenes and Staphylococcus aureus, by using the submerged cultivation method), but also the possibility of deg...
Biointerface Research in Applied Chemistry, 2019
A new green deposition of silver nanoparticles (AgNPs) on polymers was proposed in this work. In-situ synthesis of AgNPs on polymers was achieved via a green procedure using natural reducing agents, which are Ageratum conyzoidez and Mikania micrantha. Several characterizations of the treated polymers such as color transformation, surface morphology, elemental contents, and water absorption were comprehensively evaluated. For the application, the treated polymers were then tested against waterborne bacteria, which are Escherichia coli and Bacillus cereus. Rapid deposition of AgNPs via the presently biological method can be successfully achieved as observed via surface morphology analysis and energy dispersive X-ray investigation. Water absorption capabilities of the polymers can be decreased after attaching with AgNPs, which can also probably contribute to the enhancement of their antibacterial activities. This study observed that the treated polymers showed excellent antibacterial a...
2017
The synthesis of silver nanoparticles (Ag-NPs) has been conducted on the biopolymer media which is sodium alginate (Na-Alg) via the green method. Different times of ultrasound irradiation was used to reduce Ag + to be Ag seed (Ag 0) and produce Ag-NPs. The Ag-NPs was analyzed in their surface plasmon resonance (SPR), morphology, biomolecule responsible, and stability via UV-Vis, TEM, FTIR and Zeta potential, respectively. The application as antibacterial properties was studied against bacteria. Furthermore, this Ag-NPs could be synthesized using the green method and used as antibacterial efficacy for medical vehicles, would dressing, and so on.
The antibacterial effect of silver has been used in a variety of commercially available products and medical devices for many years, either in its metallic or salt form. Nowadays, due to the knowledge acquired within the last decade in the field of Nanoscience and Nanotechnology, the use of silver nanoparticles (AgNPs) for medical and sanitary purposes has been thoroughly studied and dramatically increased. One of the major concerns dealing with the use of AgNPs in human health and disinfection is, in fact, its toxicity what dictates the need to use safe strategies for AgNPs applications. Nanocomposites are a good approach since the mobility of the nanoobjects is reduced whereas their activity remains. In this context, the Intermatrix Synthesis technique provides a novel route for both synthesis and immobilisation of AgNPs in commercially available ion-exchange matrices. This chapter reviews the state-of-the-art of the nanotechnological approach in bactericidal application of AgNPs ...
With the increasing concern over drug-resistant bacterial infections, in particular hospital-acquired infections , there is an urgent need to develop effective and safe antibacterial agents. Herein, a study aiming at developing a good antibacterial agent with high antibacterial activity and low cytotoxicity to promote public health is reported. Composite copolymer hybrid silver nanoparticles (AgNPs) were synthesized via the reduction of NaBH 4 in the presence of copolymers and AgNO 3. The composite copolymers containing 2-(dimethylamino)ethyl methacrylate (DMAEMA) and poly(ethylene glycol) methyl ether methacrylate (PEGMA) segments were prepared by reversible addition–fragmentation chain transfer (RAFT) polymeriz-ation, and then the copolymers were quaternized to increase AgNPs adhesion to bacterial membranes through electrostatic interactions. The copolymer hybrid AgNPs showed high antibacterial activity against P. aeruginosa (Gram-negative bacteria) and S. aureus (Gram-positive bacteria), which could inhibit bacterial proliferation even if the concentration was 8 µg mL −1. Furthermore, copolymer hybrid AgNPs had negligible haemolysis and low cytotoxicity. The nanoparticles destroyed the bacterial membrane irreversibly and then caused the release of cytoplasmic constituents and cell death finally. These results suggest that copolymer hybrid AgNPs have potential use as antibacterial agents in clinical applications.
Polymer Engineering & Science, 2011
Medical applications require, in most cases, antibacterial protection. The use of silver (Ag) gives important antibacterial properties since silver is highly toxic for bacteria. In this research work, we have used silver nanoparticles (Ag NPs) with different surfactants, polyvinyl pyrrolidone (PVP) and oleic acid (OA) to facilitate dispersion. PP-Ag NPs compounds were prepared by melt mixing, and the effects of the processing conditions on nanoparticles' dispersion were investigated by transmission electron microscopy (TEM). The antibacterial efficiency of PP-Ag NPs compounds against Staphylococcus aureus ATCC 6538 and Escherichia coli ATCC 8379 was evaluated. Results show that good dispersion is obtained with rotating speeds in the 350-500 rpm range. TEM analysis reveals balanced dispersion and presence of some Ag NPs aggregates. Regarding antimicrobial properties, the use of PVP as surfactant leads to ' 'significant'' antimicrobial activity of 1.5 against Staphylococcus aureus and Escherichia coli; on other hand, the use of oleic acid (OA) as surfactant leads to strong protection against Staphylococcus aureus (antimicrobial activity between 2.5 and 3.3) but the overall protection against Escherichia coli is very low (lower than 1). Results show that the use of surfactants for Ag NPs has important effects on antibacterial properties of polypropylene filled with coated Ag NPs. POLYM. ENG.
Research in Microbiology, 2011
The purpose of this study was to investigate the antibacterial effect of silver nanoparticles in chitosan-poly(ethylene glycol) suspension. The silver nanoparticles (AgNPs) were prepared by use of an environmentally benign method from chitosan (Cts) and poly(ethylene glycol) (PEG) at moderate temperature and with stirring for different times. Silver nitrate (AgNO 3 ) was used as the metal precursor and Cts and PEG were used as solid support and polymeric stabilizer, respectively. The antibacterial activity of silver-chitosan-poly(ethylene glycol) nanocomposites (Ag-Cts-PEG NCs) against Staphylococcus aureus, Micrococcus luteum, Pseudomonas aeruginosa, and Escherichia coli was tested by use of the Mueller-Hinton agar disk-diffusion method. Formation of AgNPs was determined by UV-visible spectroscopy; surface plasmon absorption maxima were observed at 415-430 nm in the UV-visible spectrum. The peaks in the XRD pattern confirmed that the AgNPs had a face-centered cubic structure; peaks of contaminated crystalline phases were not observed. Transmission electron microscopy (TEM) revealed that the AgNPs synthesized were spherical. The optimum stirring time for synthesis of the smallest particle size (mean diameter 5.50 nm) was 12 h. The AgNPs in Cts-PEG were effective against all the bacteria tested. Higher antibacterial activity was observed for AgNPs with smaller size. These results suggest that AgNPs can be used as an effective inhibitor of bacteria and can be used in medical applications. These results also suggest that AgNPs were successfully synthesized in Cts-PEG suspension at moderate temperature with different stirring times.
Zeitschrift für Naturforschung B, 2011
This study describes the development of a preparation technique for silver nanoparticles useable as antimicrobial material which is especially useful for textile treatment to realize antimicrobial fabrics. The silver particles need to be prepared by reduction of AgNO 3 under moderate conditions and with a moderate and non-toxic reductive agent. Comparative investigations were carried out with silver particles prepared by a solvothermal process or with NaBH 4 as reductive agent. Particularly, suitable silver solutions are obtained by stabilizing the silver particles with polyvinylpyrollidone PVP of high molecular weight (M w ∼ 360000 g mol -1 ) and the use of the non-toxic reductive agents ascorbic acid and fructose. Under these conditions the diameters of the silver particles are in the range of 10 to 30 nm as determined by HR-TEM. The formation of elemental silver has been verified by transmission electron microscopy (TEM), X-ray diffraction (XRD) and optical spectroscopy. The properties of silver particle-containing liquids were investigated by using UV/Vis spectroscopy and dynamic light scattering. Further information on particle size and size distribution was gained through SEM investigations. The prepared solutions of silver nanoparticles can be applied easily onto textiles as liquid coating agents. All prepared textile samples exhibited a high antimicrobial activity against Escherichia coli. However, only few solutions containing silver particles of smaller size exhibit high antimicrobial activity also against other types of bacteria such as Staphylococcus aureus and Streptococcus pneumoniae. Because of this high antimicrobial potential gained with silver solutions prepared in a simple process without usage of toxic components, the developed materials offer a broad range of potential applications.
International Journal for Research in Applied Science and Engineering Technology, 2021
Polypropylene/silver nanoparticles nanocomposite films were prepared by melt compounding method by using polypropylene pallets and silver nanoparticles powder. The physical properties of the virgin polypropylene film and nanocomposite films were evaluated by mechanical testing. The effect of various silver nanoparticles content in the polymer nanocomposites with respect to its antimicrobial efficacy against the Gram positive bacteria Escherichia coli and Gram positive bacteria Staphylococcus aureus were studied. Nanocomposite film containing higher percentage of silver nanoparticles loading showed 99.9 % efficacy against the bacteria as compared to virgin polypropylene film.
Chemistry Central Journal, 2012
This study aims to investigate the influence of different stirring times on antibacterial activity of silver nanoparticles in polyethylene glycol (PEG) suspension. The silver nanoparticles (Ag-NPs) were prepared by green synthesis method using green agents, polyethylene glycol (PEG) under moderate temperature at different stirring times. Silver nitrate (AgNO 3 ) was taken as the metal precursor while PEG was used as the solid support and polymeric stabilizer. The antibacterial activity of different sizes of nanosilver was investigated against Gram-positive [Staphylococcus aureus] and Gram-negative bacteria [Salmonella typhimurium SL1344] by the disk diffusion method using Müeller-Hinton Agar.
Journal of Nanomaterials, 2012
A simple technique based on doping polymers within situgenerated silver nanoparticles (Ag/PS films) has been developed. In particular, an antiseptic material has been prepared by dissolving silver 1,5-cyclooctadiene-hexafluoroacetylacetonate in amorphous polystyrene, and the obtained solid solution has been heated for ca. 10 s at a convenient temperature (180°C). Under such conditions the metal precursor decomposes producing silver atoms that diffuse into the polymer and clusterize. The antimicrobial characteristics of the resulting polystyrene-based material have been accurately evaluated towardEscherichia coli (E. coli)comparing the cytotoxicity effect of 10 wt.% and 30 wt.% (drastic and mild annealing) silver-doped polystyrene to the corresponding pure micrometric silver powder. Two different bacterial viability assays were performed in order to demonstrate the cytotoxic effect of Ag/PS films on culturedE. coli: (1) turbidimetric determination of optical density; (2) BacLight flu...
International Journal of Manufacturing Economics and Management, 2022
The need to find materials for various common objects and more reliable and less expensive production is a major concern of society and scientists in recent decades, due to the dramatic decline in available stocks of materials from low renewable resources and massive pollution caused by the production of cement, brick, plastics or other similar products. In this sense, the use of biodegradable plastics is a more than the satisfactory alternative. However, in order to grow their performance, they constantly need to be improved, so composite materials based on biodegradable or recyclable polymers have started to be used frequently as a viable alternative. The present manuscript reveals the mechanical behavior of such composite material obtained by coating Arboblend V2 Nature granules with silver nanoparticles (AgNPs). The coating is intended to improve the antibacterial activity of the base material. The obtained results underlined the fact that with the incorporation of AgNPs in the polymer mass, the mechanical performances (tensile strength, bending strength, elongation, modulus of elasticity) of the material decrease visibly. Thus, the possibility of use of the parts in applications that involve exposure to pulling or bending is quite low, but can successfully replace other biodegradable/nonbiodegradable polymeric materials that have metal particles in their structure and which do not present antibacterial action.
Polymers, 2021
The paper aims to investigate the behavior of Arboblend V2 Nature biopolymer samples covered with three ceramic powders, Amdry 6420 (Cr2O3), Metco 143 (ZrO2 18TiO2 10Y2O3) and Metco 136F (Cr2O3-xSiO2-yTiO2). The coated samples were obtained by injection molding, and the micropowder deposition was achieved by using the Atmospheric Plasma Spray (APS) method, with varied thickness layers. The present study will only describe the results for nine-layer deposition because, as the number of layers’ increases, the surface quality and mechanical/thermal characteristics such as wear, hardness and thermal resistance are also increased. The followed determinations were conducted: the adhesion strength, hardness on a microscopic scale by micro-indentation, thermal analysis and structural and morphological analysis. The structural analysis has highlighted a uniform deposition for the ZrO2 18TiO2 10Y2O3 layer, but for the layers that contained Cr2O3 ceramic microparticles, the deposition was not ...
International Journal of Modern Manufacturing Technologies
Thermal behavior in plastic materials has a strong influence on their performance. In the current research, scientists are using different equipment that highlights the calorimetric behavior of parts by the identification and localization of transitions and exothermic/endothermic reactions that take place during material heating. The paper aims to characterize from a thermal point of view a lignin-based polymer (Arboblend V2 Nature) coated with three distinct micro-ceramic powders: two based on chrome oxide - Cr2O3, Cr2O3 -xSiO2 -yTiO2 (commercial name Amdry 6420 and Metco 136F) and one based on zirconium oxide - ZrO2 18TiO2 10Y2O3 (commercially known as Metco 143). The samples to be covered were obtained by injection in the mold and the coating technique used was a thermal – APS (Atmospheric Plasma Spray). After thermal analysis, all three coated samples reviled thermal stability up to 230°C, the degradation of the lignin matrix taking place around 345°C. Thus, based on this import...
Journal of Polymer Research, 2012
Poly(acrylic acid)/Silver, PAA/Ag, nanocomposite, was in-situ synthesized by radical polymerisation of acrylic acid (AA) monomers, using AIBN as initiator and ethanol as solvent in presence of silver nitrate AgNO 3 nanoparticles. It was found that polymerisation of (AA) monomers and reduction of silver ions occurred simultaneously, thereby leading to the formation of the PAA/Ag nanocomposite. The obtained material was characterized by infrared (IR), UV-visible, photo-luminescence measurements, X-Ray powder diffraction (XRD), and scanning electron microscopy (SEM). Strong interactions between silver ions and carboxylic groups of PAA, were identified by FT-IR spectroscopy. Highly luminescent single colloidal silver nanoparticles under blue excitation were detected by photoluminescence spectroscopy. Scanning electron microscopy (SEM), image revealed that silver nanoparticles were well dispersed in PAA matrix. X-ray powder diffraction XRD pattern, showed the appearance of small picks corresponding to the face centred cubic (f.c.c.) silver phase. Furthermore the antimicrobial activity of Ag nanoparticles was investigated against, Staphylococcus aureus and Candida albicans micro-organisms. It was found that the carboxylic groups from the acrylic acid favour silver ions mobility in the organic matrix. Thus they are expected to be liable to the enhancement of the antimicrobial surface activity in this hybrid material. The results suggest that PAA/ Ag nanocomposite can be used as effective growth inhibitors in various micro-organisms, making them appropriate to diverse medical devices and antimicrobial control systems.
NANOSCIENCE AND NANOTECHNOLOGY: NANO-SciTech
Polystyrene has been widely used as everyday materials and silver has been found as an anti-bacterial agent. Combination of polystyrene and silver into a polymer-metal composites (PS/ Ag NCs) could merge both properties. Polystyrene can be modify through many routes, while silver nanoparticles can be manipulated to serve as antimicrobial and drug delivery agent. The present study uses expanded polystyrene which was dissolved in Tetrahydrofuran (THF) and doped with silver nanoparticles synthesized through leaf extract of Parthenium. The PS/Ag NCs were investigated by UV-Vis spectroscopy and Atomic Force Microscopy (AFM). The analysis of various synthesis of PS/Ag NCs with different PS:Ag ratio create complex nanocomposites. UV-Vis spectrum of 435 nm indicated the effect of Localize Surface Plasmon resonance of silver nanosize confirmed the nanosize of Silver nanoparticles that are ready to be used anti-bacterial agent. Future works will be looked into modifying the polymer (Polystyrene) structure to be used as attachment surfaces for drug molecules for drug delivery system, thus serves as bi-functional composite that not only useful for drug delivery system and as anti-bacterial agent as well.
Advanced Materials Letters, 2016
In the present study, the extracellular phycofabrication (synthesis by algae) of silver nanoparticles was demonstrated using algae i.e. Spirogyra sp. recovered from the fresh water. The reduction of silver ions present in the aqueous solution of silver sulphate (Ag2SO4) was done by the cell filtrate of Spirogyra sp. leading to the synthesis of silver nanoparticles. Phycofabrication of silver nanoparticles was confirmed by using characterization tools like UV-Vis spectrophotometer, FTIR, TEM and NTA. The resulting silver nanoparticles were spherical in shape, in the range of 40-80 nm and capped with proteins. Through the experimental studies, it was found that temperature, pH and salt concentration affects the rate of phycofabrication of silver nanoparticles. Antibacterial study of phycofabricated silver nanoparticles was assessed against human pathogenic bacteria. These silver nanoparticles showed better antibacterial activity against Gram positive bacteria i.e. Staphylococcus aureus (ATCC-25923) (13 mm) as compared to Gram negative bacteria i.e. Escherichia coli JM-103 (ATCC-39403) (11 mm). This is the first report of synthesis of silver nanoparticles by Spirogyra sp. using Ag2SO4 as a salt. Extracellular phycofabrication of silver nanoparticles by Spirogyra sp. was found be easy, simple and eco-friendly method.
2012
Various types of polymers are currently used for making indirect restorations for rehabilitation of patient in dentistry. Most of these lack inherent antimicrobial property. The aim of this study was to develop and characterize antimicrobial polymer by impregnation with silver nanoparticle which besides serving its primary function also possess antimicrobial property. This study was conducted during MSc, Dental material programme, year 2010-11 in School of Engineering and Material Sciences, Queen Mary, University of London, UK under supervision of Professor Pankaj Vadgama. For this purpose polydimethylsiloxane(PDMS) based poly ether urethane(PEU) was selected to synthesize antimicrobial polymer. In methodology ultraviolet visible spectroscopy was used to detect size and shape and interaction of matrix with nanoparticles. Thermogravimetric analysis was employed to determine the thermal stability, degradation pattern, absorption of moisture and inorganic content .Contact angle measure...
Journal of Biomedical Materials Research Part A, 2013
Plasma polymerized polyacrylic acid (PPAA) was deposited on a polymer substrate, namely polyethylene terephthalate (PET) mesh, for entrapment of silver nanoparticle (Ag-NP) in order to achieve antibacterial property to the material. Carboxylic groups of PPAA act as anchor as well as capping and stabilizing agents for Ag-NPs synthesized by chemical reduction method using NaBH 4 as a reducing agent. Fourier transform infrared spectroscopy, X-ray photoelectron spectroscopy (XPS), and water contact angle analysis were used to characterize the PPAA coatings. The Ag-NPs loaded polymer samples were characterized by UV-visible spectroscopy, field emission scanning electron microscopy, energy dispersive X-ray, and XPS techniques. XPS analysis showed $1.0 at.% loading of Ag-NPs on to the PPAA-PET-mesh, which was composed of 79% zero-valent (Ag o ) and 21% oxidized nano-Ag (Ag þ ). The plasma processed PET meshes samples were tested for antibacterial activity against two bacterial strains, namely Staphylococcus aureus (Gram positive) and Escherichia coli (Gram negative). Qualitative and quantitative tests showed that silver containing PPAA-PET meshes exhibit excellent antibacterial property against the tested bacteria with percent reduction of bacterial concentration >99%, compared to the untreated PET mesh. V C 2012 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 00A:000-000, 2012.
Oriental Journal of Chemistry, 2014
International Journal …, 2010
In this study, antibacterial characteristic of silver/poly (lactic acid) nanocomposite (Ag/PLA-NC) films was investigated, while silver nanoparticles (Ag-NPs) were synthesized into biodegradable PLA via chemical reduction method in diphase solvent. Silver nitrate and sodium borohydride were respectively used as a silver precursor and reducing agent in the PLA, which acted as a polymeric matrix and stabilizer. Meanwhile, the properties of Ag/PLA-NCs were studied as a function of the Ag-NP weight percentages (8, 16, and 32 wt% respectively), in relation to the use of PLA. The morphology of the Ag/PLA-NC films and the distribution of the Ag-NPs were also characterized. The silver ions released from the Ag/PLA-NC films and their antibacterial activities were scrutinized. The antibacterial activities of the Ag/PLA-NC films were examined against Gram-negative bacteria (Escherichia coli and Vibrio parahaemolyticus) and Gram-positive bacteria (Staphylococcus aureus) by diffusion method using Muller–Hinton agar. The results indicated that Ag/PLA-NC films possessed a strong antibacterial activity with the increase in the percentage of Ag-NPs in the PLA. Thus, Ag/PLA-NC films can be used as an antibacterial scaffold for tissue engineering and medical application.
International Nano Letters, 2015
We present silver nanoparticles as the new age broad spectrum antibiotic. Siver nanoparticles exhibit unique physical and chemical properties that make them suitable for understanding their biological potential as antimicrobials. In this study, we explored the antibacterial activity of silver nanoparticles (TSC-AgNPs) and silver nanoparticles doped with polyvinylpyrrolidone (PVP-AgNPs) against Gram-negative and Gram-positive bacteria, Escherichia coli (DH5a) and Staphylococcus aureus, (ATCC 13709). Nucleation and growth kinetics during the synthesis process of AgNPs were precisely controlled using citrate (TSC) and further doped with polyvinylpyrrolidone (PVP). This resulted in the formation of two different sized nanoparticles 34 and 54 nm with PDI of 0.426 and 0.643. The physical characterization was done by nanoparticle tracking analysis and scanning electron microscopy, the results of which are in unison with the digital light scattering data. We found the bactericidal effect for both TSC-AgNPs and PVP-AgNPs to be dose-dependent as determined by the minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) against E. coli and S. aureus. Interestingly, we also observed that AgNPs showed enhanced antimicrobial activity with a MIC of 26.75 and 13.48 lg/ml for E. coli and S. aureus, respectively, while MBC for AgNPs are 53.23 and 26.75 lg/ml for E. coli and S. aureus, respectively. Moreover, AgNPs showed increased DNA degradation as observed confirming its higher efficacy as antibacterial agent than the PVP doped AgNPs.
IJRASET, 2021
Polymeric films which can be used in packaging industries were prepared by blown film method with polypropylene chips and silver nanoparticles. The nanocomposite films were characterized concerning its potential use. Oxygen Transmission rate (OTR) measurements was done in order to ascertain permeability of oxygen through the polymeric films. It was found that the permeability of oxygen through nanocomposite film is higher than that of virgin polypropylene film due to incompatibility between polypropylene matrix and silver nanoparticles. The water vapour transmission rate (WVTR) test of the polymeric nanocomposite films was calculated in order to know the information about mass transfer mechanisms and solute-polymer interactions in the food packaging film. It has been found that, there is a significant decreased water vapour transmission rate through nanocomposite films compared to that of virgin polypropylene film. With increasing the concentration of silver nanoparticles, this effect was reduced. The explanation for this could be that with higher concentration of silver nanoparticles agglomeration in the polymer film could the possibility which create narrow pathway for water molecules to travel. The effect of various silver nanoparticles content in the polymer nanocomposites with respect to its antimicrobial efficacy against the Gram positive bacteria Escherichia coli and Gram positive bacteria Staphylococcus aureus were studied. However, Escherichia coli was most effectively retarded by silver nanoparticles than Staphylococcus aureus, which is related to the difference in the cell wall of the gram positive and gram negative bacteria.
Polímeros, 2010
Commercial copolymers based on styrene and divinylbenzene containing sulfonic acid groups were used as support for the incorporation of silver nanoparticles. These nanoparticles were obtained in situ by the reduction of Ag + by using hydroxylamine in the presence of a protective agent. These materials were characterized with determination of the silver content and their morphological characteristics. The antibacterial activity of the final products against Escherichia coli was evaluated and the results show that the synthesized copolymers had antibacterial effect varying from 54 to 100%. The most efficient composite was made with small, well distributed particles.
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