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Images showing the inhibition zone in the developing bacterial lawns after 24 h at 37 C. (A) Samples as control; 1: zirconiaepolyether solegel films þ AOT/Isooctane, 2: zirconiaepolyether solegel films, 3: zirconiaepolyether solegel films þ AgNO3. (B) Zirconiaepolyether solegel films supporting different AgNps contents; 85, 140, 212, 255 and 283 mg mL À1 AgNps are marked 1,2,3,4 and 5 respectively.
Source publication
The antimicrobial effect of incorporating silver nanoparticles (AgNps) into zirconia matrixepolyether
glycol was studied. AgNps of 4e6 nm in size were synthesized using the inverse micelles method, and
different doses of metallic nanoparticles were incorporated into zirconiaepolyether glycol mixtures
during the ageing procedure. Atomic force micros...
Contexts in source publication
Context 1
... procedure on MH-agar medium [12]. Controls were performed to rule out the possible antibacterial effect of i) zirconiaepolyether solegel films þ AOT/Isooctane; ii) zirconiaepolyether solegel films and iii) zirconiaepolyether solegel films þ AgNO 3 , through inoculation of bacteria in the respective medium without silver nanoparticles (Ag-Np). Fig. 8A shows the zirconiaepolyether glycol film mixed with the AOT/isooctane system (labelled 1), zirconia- polyether glycol (labelled 2) and AgNO 3 (labelled ...
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... Fig. 8A, the film supported on a disc is not able to create a zone of inhibition in bacterial growth, which implies that neither the hybrid polymer, nor the incorporated AOT, have antibacterial capacity. AgNO 3 even at very high concentration (450 mg mL À1 , Fig. 7. Contact mode AFM image (4 mm in size, displaying deflection signal) of ...
Context 3
... (450 mg mL À1 , Fig. 7. Contact mode AFM image (4 mm in size, displaying deflection signal) of unmodified and silver nanoparticles modified zirconiaepolyether glycol hybrid films; top view and cross section view. 0.3 wt%) was not able to show activity, revealing only a brown spot around the sample and a little inhibition zone of less than 10 mm. Fig. 8B reveals the inhibition zone in the bacterial lawn for each different AgNps content. In comparison to the results shown in Fig. 8A, silver nanoparticles at even the lowest concentration (85 mg AgNp mL À1 , labelled 1) displayed better results in L. monocytogenes and S. aureus than AgNO 3 . Thus, both Gram- positive bacteria tested, S. ...
Context 4
... modified zirconiaepolyether glycol hybrid films; top view and cross section view. 0.3 wt%) was not able to show activity, revealing only a brown spot around the sample and a little inhibition zone of less than 10 mm. Fig. 8B reveals the inhibition zone in the bacterial lawn for each different AgNps content. In comparison to the results shown in Fig. 8A, silver nanoparticles at even the lowest concentration (85 mg AgNp mL À1 , labelled 1) displayed better results in L. monocytogenes and S. aureus than AgNO 3 . Thus, both Gram- positive bacteria tested, S. aureus and L. monocytogenes, show a greater sensibility to silver nanoparticles. In contrast S. typhi and E. coli, both ...
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Silver nanoparticles were synthesized in sodium bis(2-ethylhexyl)-sulfosuccinate (AOT) reverse micelles in isooctane with tetraethylene glycol dodecyl ether (C 12 E 4) as a cosurfactant. Recovery of the Ag particles from the reverse micelles by dissolving antisol-vent CO 2 in the micellar solution was investigated. All the Ag particles in the rever...
Citations
... Individual bacterial colonies were meticulously collected using sterile inoculating rings and subsequently cultured in a suitable broth medium within the incubator for an additional 24 h to yield bacterial suspensions for subsequent experimentation. The antimicrobial efficacy of the OEO composite film against tested strains was assessed using the disc diffusion method (Azócar et al. 2012). Initially, different volumes of OEO were incorporated into the composite films: a low volume (1 mL), a medium volume (3 mL), and a high volume (5 mL). ...
... The bands observed at 1215 cm −1 and 1017 cm −1 are assigned to the symmetric and asymmetric stretching of sulfonated groups (-SO 4 ) in SDS, respectively [21]. The bands at 3387 cm −1 in AgFilm and 3312 cm −1 in AgNPs can be attributed to hydroxyl group stretching vibrations [22]. ...
... The synthesis conditions of AgNPs can vary and incorporate other substances. In this study, SDS was used as a stabilizer, sodium hydroxide as a catalyst, and sorbitol to provide elasticity to AgFilm [21,30,31]. The embedding of AgNPs into the film was performed by an ex-situ method, which consists in adding the as-prepared AgNPs to agar. ...
The high incidence of Candida albicans infections has raised concerns regarding side effects and drug resistance, compounded by a limited number of alternative drugs. Silver nanoparticles (AgNPs) have prominent antimicrobial activity, but effective administration remains a challenge. In this study, AgNPs were synthesized via a green chemistry approach, using glucose as a reducing agent, and incorporated into an agar matrix to form a film (AgFilm). The AgNPs and AgFilm were characterized by Ultraviolet–visible (UV–vis) spectroscopy, Fourier transform infrared (FTIR) spectroscopy, dynamic light scattering (DLS), powder X-ray diffraction (PXRD), scanning electron microscopy (SEM), and atomic force microscopic (AFM). The UV–Vis spectra of the AgNPs and AgFilm showed bands at 415 and 413 nm, respectively. The PXRD and UV–Vis data suggest that the growth of AgNPs was effectively inhibited in the AgFilm. The diameter of AgNPs dispersed in AgFilm was 76 ± 42 nm, and the thickness of the film and 35 ± 3 µm. The antifungal activity of AgFilm was evaluated against 20 strains of C. albicans, demonstrating high antifungal activity with an inhibition zone of 19 ± 2 mm. Therefore, AgFilm could be a promising option for the treatment of superficial C. albicans infections.
... In the fi ltration process the ceramic membranes are widely used. This is due to their properties, among which mechanical strength, chemical and high temperature resistance, ease of cleaning (Koyuncu et al. 2015, Narong andJames 2008) and also microbial resistance, resulting from a nanometric metal particles (silver) addition to a membrane (Lv et al. 2009, Azócar et al. 2012, can be distinguished. In these respects, ceramic membranes surpass polymeric membranes (Kumar et al. 2015, Narong andJames 2008) which in order to improve their properties are modifi ed by doping with nanometric, inorganic particles, such as ZrO 2 , Al 2 O 3 , TiO 2 and SiO 2 . ...
... The antibacterial properties and other unique features of zirconium modified materials have been recorded thus promoting their effectiveness for a broad range of applications [67]. In the study by Masim et al. [68] the antibacterial properties of polyaniline functionalized with zirconium dioxide (PANI-ZrO 2 ) towards E. coli and S. aureus was assessed using the agar diffusion test method. ...
The presence of pollutants (chemical and biological in nature) in wastewater in recent times has been a source of concern due to the vital role of clean water in the propagation of life on this earth. Therefore, the development of adsorbents with antibacterial properties for the remediation of wastewater using a simple but efficient technique such as the adsorption process offers significant benefits. This review is thus aimed at presenting some types of materials and their suitability for the development of adsorbents with antibacterial properties. Due to the ease and other associated benefits of the adsorption technique, only materials that were applied as adsorbents and also exhibit antibacterial properties are presented. Although some materials show intrinsic antibacterial properties, the introduction of some modification agents can be useful in enhancing their efficiency as well as resulting in the development of new materials with antibacterial properties and other properties. The underlying mechanism(s) for the inhibition of microorganisms by these adsorbents are also discussed. In addition, challenges associated with the application of these adsorbents for wastewater treatment as well as some recommendations to address them are presented. This report is aimed at helping in the design of novel adsorbents with the ability to remove both chemical and biological pollutants so as to promote their prospect for practical application.
... According to the test method of Azócar et al. [22] with slightly modified. In the aseptic culture dish, L. monocytogenes and E. coli were respectively added to the culture dish, the agar medium with 46 °C was poured into and spread evenly and then placed 5 min. ...
Polyvinyl alcohol/oregano oil/graphene oxide antibacterial composite film was prepared from PVA and GO by adding OEO as the antibacterial agent. The effect of different OEO contents on the properties of the composite film was studied. The results showed that the OEO improved the performance of the composite film. With the increase of OEO content, the thicknesses were increased, the mechanical properties were improved, and the antibacterial activities were increased. The performances of the film with 1% OEO were the best. The tensile fracture elongation and the tensile strength were 249% and 20.760 MPa, respestively. The diameter of the antibacterial ring of E. coli and L. monocytogenes was 11.70 mm and 12.61 mm, respectively. FTIR revealed that there were chemical bonds among PVA, GO and OEO. SEM showed that OEO made the surface of the composite film smoother. TGA showed that OEO did not affect the coke yield of composite films. DSC indicated that OEO reduced the exothermicity of composite films. The antibacterial properties of natural essential oils were taken advantage of to make the antibacterial composite films, which was beneficial to expand the use of essential oils in packaging films, and provides a reliable reference for other researchers.
... At the same time the excited electrons in conduction band undergoes reduction process with oxygen molecules to give superoxide anion O 2•− subsequently it reacts with water molecule to produce H 2 O 2 . Hydrogen peroxide is a very good oxidizing agent which is easily undergoes into the cell to destroy the micro-organism, but hydroxyl ions and super oxide anions doesn't penetrate the cell, they hang around on outer layer of the cell and disturb the proteins, DNA and lipids [52][53][54]. The schematic representation of mechanism of bacterial inhibition takes place via oxidation and reduction process is shown in Fig. 13 responsible for enhancement of zone of inhibition of the composite finally gives good result [16]. ...
... The antimicrobial properties of modified natural polymers are of great interest (Kukharenko et al. 2014;Littunen et al. 2016), but the mobility and potential migration of silver in such materials can be problematic. The antimicrobial properties of different porous materials are also still being tested (Wang et al. 2006;Yang et al. 2009;Azócar et al. 2012;Nassar and Youssef 2012;Youssef et al. 2013), and zeolites seem to be the best alternative because of their mechanical resistivity, sorptive and catalytic properties which can eliminate or decrease the problem of environmental risks. ...
The study is devoted to manufacturing and characterising a new paper material with antimicrobial properties, as an alternative to paper containing silver nanoparticles (NPs) which are claimed to be harmful to the ecosphere. In place of silver NPs, the new material contains faujasite mineral (from the faujasite group) exchanged with silver cations which are firmly attached to the material’s lattice. The material was obtained by typical ion exchange and additional elution with EDTA salt to dispose of the remaining silver oxide NPs. Thus, modified faujasite was then added to paper pulp. The new, modified paper showed better quality in terms of acidity, tensile strength and cellulose degree of polymerisation compared to paper containing Ag NPs. The visual quality of the paper is also better than that containing Ag NPs. The new material shows high potential for use in food and pharmaceutics packaging.
... In the fi ltration process the ceramic membranes are widely used. This is due to their properties, among which mechanical strength, chemical and high temperature resistance, ease of cleaning (Koyuncu et al. 2015, Narong andJames 2008) and also microbial resistance, resulting from a nanometric metal particles (silver) addition to a membrane (Lv et al. 2009, Azócar et al. 2012, can be distinguished. In these respects, ceramic membranes surpass polymeric membranes (Kumar et al. 2015, Narong andJames 2008) which in order to improve their properties are modifi ed by doping with nanometric, inorganic particles, such as ZrO 2 , Al 2 O 3 , TiO 2 and SiO 2 . ...
The goal of this article was to review the literature which discusses the problem of oily wastewater purification by membrane filtration. The authors focused on membranes containing zirconium compounds, mainly ZrO2, used in pressure driven membrane processes. The efficiency of the oil removal processes for various membranes (ceramic and composite), usually above 95% for the oil contaminated sewage, was compared. The influence of zirconium compounds on the properties of ceramic membranes was also discussed. The methods of producing ceramic membranes have been briefly characterized as well. Ceramic membranes are usually obtained by sol-gel technique but also by isostatic compression, reverse phase technique, or hydrothermal crystallization. Ceramic membranes are formed with zirconia, which cause an increase in filtration efficiency by improvement of hydrophilic properties of the membrane. Moreover, the addition of ZrO2 results in increased chemical and hydrothermal membrane stability. The efficiency of the filtration processes using the presented membranes was high, suggesting that membrane filtration processes are highly effective purification methods. © Copyright by Polish Academy of Sciences and Institute of Environmental Engineering of the Polish Academy of Sciences, Zabrze, Poland 2018.
... ZrO 2 nanoparticles are regarded as effective antibacterial and anti-corrosion agents with a number of excellent properties, such as high strength, fracture toughness, wear resistance, hardness, and chemical resistance [9,10]. For example, studies on ZnO-ZrO 2 nanocomposite-doped polyaniline (PANI) show an improved thermal stability, good electrical conductivity, and enhanced antibacterial activity against two Grampositive bacteria, Staphylococcus aureus (MSSA- 22) and Bacillus subtilis (ATCC-6051), and two Gram-negative, bacteria Escherichia coli (K-12) and Pseudomonas aureginosa (MTCC-2488) strains, using a broth dilution method [1]. ...
The increasing number of bacteria-related problems and presence of trace amounts of phosphate in treated wastewater effluents have been become a growing concern in environmental research. The use of antibacterial agents and phosphate adsorbents for the treatment of wastewater effluents are of great importance. In this study, the potential applications of a synthesized PANI-ZrO2composite as an antibacterial, phosphate adsorbent and anti-corrosion material were systematically investigated. The results of an antibacterial test reveal an effective area of inhibition of 14 and 18 mm for the E. coli and S. aureus bacterial strains, respectively. The antibacterial efficiency of PANI-ZrO2 composite is twice that of commercial ZrO2. In particular, the introduction of PANI increased the specific surface area and roughness of the composite material, which was beneficial to increase the contact area with bacterial and phosphate. The experimental results demonstrated that phosphate adsorption studies using 200 mg P/L phosphate solution showed a significant phosphate removal efficiency of 64.4%, and the maximum adsorption capacity of phosphate on the solid surface of PANI-ZrO2 is 32.4 mg P/g. Furthermore, PANI-ZrO2 coated on iron substrate was tested for anti-corrosion studies by a natural salt spray test (7.5% NaCl), which resulted in the formation of no rust. To the best of our knowledge, no works have been reported on the synergistic effects of PANI-ZrO2 composite as an antibacterial, anti-corrosion, and phosphate adsorbent material. PANI-ZrO2 composite is expected to be a promising comprehensive treatment method for water filters in the aquaculture industry and for use in water purification applications.
Key words: antibacterial activity, zirconia, polyaniline, composite, phosphate removal, corrosion protection
... Thus, Zirconia based nonmaterial as antibacterial component have been used in dental ceramic, and their coating of medical devices [17][18][19]. Recently, Ignacio Azocar and co-workers reported that hybrids of Zirconia with silver NPs [20]. To our knowledge, the antibacterial activity of Zirconia is well known one and it has been studied in detail [20,21], whereas, the antibacterial active and nontoxic element of Zirconia in the form of nanoparticles, has not been reported in the literature. ...
... Recently, Ignacio Azocar and co-workers reported that hybrids of Zirconia with silver NPs [20]. To our knowledge, the antibacterial activity of Zirconia is well known one and it has been studied in detail [20,21], whereas, the antibacterial active and nontoxic element of Zirconia in the form of nanoparticles, has not been reported in the literature. ...
