Preparation and Antibacterial Activity of Silver Ions-Substituted Hydroxyapatite/Titania

2006 ◽  
Vol 510-511 ◽  
pp. 78-81 ◽  
Author(s):  
Guo Yu Lv ◽  
Yu Bao Li ◽  
Ai Ping Yang ◽  
Xiang Zhang ◽  
Wei Hu Yang ◽  
...  

In this paper a series of silver ions-substituted hydroxyapatites (HA) were prepared. The antibacterial activities of these materials on textiles against bacteria have been investigated. Titania (TiO2) was selectively added into the materials to decrease the silver-ions concentration to get the same active antimicrobial effects. The microstructure, the shape and size, concentration of silver, and the groups of the composite materials were characterized using transmission electron microscopy (TEM), infrared spectroscopy (IR), Atomic absorption spectroscopy (AAS), and X-ray diffraction (XRD). The results showed that there was a dose dependent-effect of silver-ions concentration from the disk diffusion test. The higher the silver-ions concentration, the better the antibacterial activity of the composite materials was. Keeping silver-ions concentration constant, the antibacterial activity of the materials for adding Titania was better than that of without Titania. Moreover, the addition of Titania would inhibit the discolouration of the composite materials. The antibacterial activities of the composite materials differentiate to some extent with the bacterial strains.

2020 ◽  
Vol 2020 ◽  
pp. 1-8
Author(s):  
Edwina Olohirere Uzunuigbe ◽  
Abidemi Paul Kappo ◽  
Sixberth Mlowe ◽  
Neerish Revaprasadu

Synthesizing nanoparticles with the less environmentally malignant approach using plant extract is of great interest; this is because most of the chemical approaches can be very costly, toxic, and time-consuming. Herein, we report the use of Acacia senegal leaf extracts to synthesize silver nanoparticles (AgNPs) using an environmentally greener approach. Silver ions were reduced using the bioactive components of the plant extracts with observable colour change from faint colourless to a brownish solution as indication of AgNP formation. The structural properties of the as-synthesized AgNPs were characterized using powder X-ray diffraction (XRD), transmission electron microscopy (TEM), Fourier transform infrared spectroscopy (FTIR), and UV-Vis absorption spectrum. Antimicrobial assessment of the as-synthesized AgNPs was explored on some strains of gram-positive and gram-negative bacteria. The obtained results indicate that the as-synthesized AgNPs are pure crystallite of cubic phase of AgNPs, fairly dispersed with a size range of 10–19 nm. The AgNPs were found to be small in size and exhibit significant antibacterial activities, suggesting that the as-synthesized AgNPs could be used in the pharmaceutical and food industries as bactericidal agents.


2013 ◽  
Vol 2013 ◽  
pp. 1-6 ◽  
Author(s):  
Solmaz Akmaz ◽  
Esra Dilaver Adıgüzel ◽  
Muzaffer Yasar ◽  
Oray Erguven

The aim of this study is to investigate the antibacterial properties and characterization of chitosan-silver nanoparticle composite materials. Chitosan-silver nanoparticle composite material was synthesized by adding AgNO3and NaOH solutions to chitosan solution at 95°C. Different concentrations (0,02 M, 0,04 M, and 0,06 M) of AgNO3were used for synthesis. Chitosan-silver nanoparticle composite materials were characterized by Transmission electron microscopy (TEM), X-ray diffraction (XRD), ultraviolet (UV) spectrophotometer, and Fourier transform infrared (FTIR) spectrometer techniques.Escherichia coli,Acinetobacter baumannii,Staphylococcus aureus,Enterococcus faecalis,Pseudomonas aeruginosa, andStreptococcus pneumoniaewere used to test the bactericidal efficiency of synthesized chitosan-Ag nanoparticle composite materials. The biological activity was determined by the minimum bacterial concentration (MBC) of the materials. Antibacterial effect of chitosan-silver nanoparticle materials was increased by increasing Ag amount of the composite materials. The presence of small amount of metal nanoparticles in the composite was enough to significantly enhance antibacterial activity as compared with pure chitosan.


Author(s):  
Gowri Shankar Krishnan ◽  
Namrata Pradhan ◽  
Masilamani K ◽  
Albin T Fleming

ABSTRACTObjective: In this study, silver nanoparticles (SNPs) were synthesized using an aqueous extract of Trainthema portulacastrum and silver ions (Ag+)which have been proven against certain pathogenic bacterial strains and hepatocellular carcinoma (HepG2) cell line.Methods: The bio fabricated nanoparticles were confirmed by surface plasmon resonance which were characterized by biophysical measuresutilizing the ultraviolet-visible spectroscopy, scanning electron microscopy (SEM), energy dispersive X-ray, and transmission electron microscope(TEM), Fourier transform infrared spectroscopy, particle size analyzer, and X-ray diffraction. Antibacterial efficacy against Enterobacter aerogens,Proteus mirabilis, Escherichia coli, Staphylococcus epidermis, and Bacillus subtilis. The effect of SNPs tested against HepG2 and NIH/3T3 cell lineexhibits a dose-dependent toxicity.Results and Conclusion: The SEM and TEM images confirmed the presence of spherical and hexagonal shape (0.3-4 μm) of nanocrystalline particleswith the size range of 11.5-29.2 nm. The average particles size of SNPs is 190.3±17.0 nm. Antibacterial activity was carried out by agar well diffusionmethod against different pathogenic bacteria of which B. subtilis showed a significant zone of inhibition 8.66 mm and 12.0 mm for aqueous plantextract and synthesized SNPs. The effect of SNPs tested against HepG2 and NIH/3T3 cell line exhibits a dose-dependent toxicity. In case of HepG2, thecell viability was decreased to 50% (IC50) at the concentration of 173.8±0.84 μg/mL. From the results, it can be concluded that the SNPs fabricatedusing green synthesis method will be a promising candidate in the biomedical field, due to its high bioactive properties.Keywords: Silver nanoparticles, Trainthema portulacastrum, Antibacterial activity, Cytotoxic activity.


2012 ◽  
Vol 2012 ◽  
pp. 1-8 ◽  
Author(s):  
Aruna Jyothi Kora ◽  
Jayaraman Arunachalam

A simple and ecofriendly procedure have been devised for the green synthesis of silver nanoparticles using the aqueous extract of gum tragacanth (Astragalus gummifer), a renewable, nontoxic natural phyto-exudate. The water soluble components in the gum act as reductants and stabilizers. The generated nanoparticles were analyzed using UV-visible spectroscopy, transmission electron microscopy, X-ray diffraction, Fourier transform-infrared spectroscopy, and Raman spectroscopy. The role of gum concentration and reaction time on the synthesis of nanoparticles was studied. By regulating the reaction conditions, spherical nanoparticles of13.1±1.0 nm size were produced. Also, the possible functional groups involved in reduction and capping of nanoparticles has been elucidated. The antibacterial activity of the fabricated nanoparticles was tested on model Gram-negative and Gram-positive bacterial strains with well-diffusion method. These nanoparticles exhibited considerable antibacterial activity on both the Gram classes of bacteria, implying their potential biomedical applications.


2018 ◽  
Vol 16 (S1) ◽  
pp. S48-S54
Author(s):  
Y. Ez zoubi ◽  
S. Lairini ◽  
A. Farah ◽  
K. Taghzouti ◽  
A. El Ouali Lalami

The purpose of this study was to determine the chemical composition and to evaluate the antioxidant and antibacterial effects of the Moroccan Artemisia herba-alba Asso essential oil against foodborne pathogens. The essential oil of Artemisia herba-alba was analyzed by gas chromatography coupled with mass spectroscopy. The antibacterial activity was assessed against three bacterial strains isolated from foodstuff and three bacterial strains referenced by the ATCC (American Type Culture Collection) using the disk diffusion assay and the macrodilution method. The antioxidant activity was evaluated using the DPPH (2, 2-diphenyl-1- picrylhydrazyl) method. The fourteen compounds of the Artemisia herba-alba essential oil were identified; the main components were identified as β-thujone, chrysanthenone, α-terpineol, α-thujone, α-pinene, and bornyl acetate. The results of the antibacterial activity obtained showed a sensitivity of the different strains to Artemisia herba-alba essential oil with an inhibition diameter of 8.50 to 17.00 mm. Concerning the MICs (minimum inhibitory concentrations), the essential oil exhibited much higher antibacterial activity with MIC values of 2.5 μl/ml against Bacillus subtilis ATCC and Lactobacillus sp. The essential oil was found to be active by inhibiting free radicals with an IC50 (concentration of an inhibitor where the response is reduced by half) value of 2.9 μg/ml. These results indicate the possible use of the essential oil on food systems as an effective inhibitor of foodborne pathogens, as a natural antioxidant, and for potential pharmaceutical applications. However, further research is needed in order to determine the toxicity, antibacterial, and antioxidant effects in edible products.


Materials ◽  
2020 ◽  
Vol 13 (21) ◽  
pp. 4715
Author(s):  
Adam Kubiak ◽  
Marta Kubacka ◽  
Elżbieta Gabała ◽  
Anna Dobrowolska ◽  
Karol Synoradzki ◽  
...  

The TiO2-Fe3O4 composite materials were fabricated via the hydrothermal-assisted technique. It was determined how the molar ratio of TiO2 to Fe3O4 influences the crystalline structure and morphology of the synthesized composite materials. The effect of the molar ratio of components on the antibacterial activity was also analyzed. On the basis of XRD patterns for the obtained titanium(IV) oxide-iron(II, III) oxide composites, the two separate crystalline forms—anatase and magnetite —were observed. Transmission electron microscopy revealed particles of cubic and tetragonal shape for TiO2 and spherical for Fe3O4. The results of low-temperature nitrogen sorption analysis indicated that an increase in the iron(II, III) oxide content leads to a decrease in the BET surface area. Moreover, the superparamagnetic properties of titanium(IV) oxide-iron(II, III) oxide composites should be noted. An important aim of the work was to determine the antibacterial activity of selected TiO2-Fe3O4 materials. For this purpose, two representative strains of bacteria, the Gram-negative Escherichia coli and Gram-positive Staphylococcus aureus, were used. The titanium(IV) oxide-iron(II, III) oxide composites demonstrated a large zone of growth inhibition for both Gram-positive and Gram-negative bacteria. Moreover, it was found that the analyzed materials can be reused as antibacterial agents in three consecutive cycles with good results.


2010 ◽  
Vol 123-125 ◽  
pp. 1291-1294 ◽  
Author(s):  
Bin Lü ◽  
Jian Zhong Ma ◽  
Dang Ge Gao ◽  
Lei Hong

Modified rapeseed oil(MRO) was prepared by using rapeseed oil, ethylene diamine and acrylic acid as the raw materials. Modified rapeseed oil/montmorillonite(MRO/MMT) nanocomposite was prepared by using modified rapeseed oil and montmorillonite. The emulsifying properties of MRO and MRO/MMT were determined respectively. Fourier transforms infrared spectrometry (FT-IR) and Transmission Electron microscope (TEM) results showed that MRO/MMT was prepared successfully. X-ray diffraction (XRD) results showed that modified rapeseed oil could smoothly enter the interlayer of montmorillonite, and modified the montmorillonite; with an increase in the amount of montmorillonite, the layer spacing of montmorillonite in the MRO/MMT lower after the first increase. The results of emulsifying properties indicated that emulsifying properties of MRO/MMT was better than MRO.


Author(s):  
Olufunmiso O. Olajuyigbe ◽  
Morenike O. Adeoye-Isijola ◽  
Otunola Adedayo

Background: Black soap is a medicinal product that could be harnessed for economic purpose if properly packaged, and misconception about its traditional use by herbalists is thrown overboard.Aims: To promote the relevance of these soaps for economic development, this study compared the antibacterial activity of black soaps with medicated soaps widely used against bacterial infections.Methods: The antibacterial activities of these soap samples were determined by agar diffusion and macrobroth dilution methods.Results: In this study, the statistical analysis of the inhibition zones showed that black soaps were significantly (p < 0.05) more active than medicated soaps used against the test bacterial isolates. The black soaps inhibited and killed the isolates better than the medicated soaps at the different concentrations used. The minimum inhibitory concentration for Klebsiella pneumoniae and Enterococcus faecalis ranged between 0.125 mg/mL and 2 mg/mL, Staphylococcus aureus (0.25–4) mg/mL, Escherichia coli (0.125–4) mg/mL and Pseudomonas aeruginosa (1–4) mg/mL. The result showed that K. pneumoniae and E. faecalis were the most susceptible, followed by E. faecalis > E. coli > S. aureus > P. aeruginosa.Conclusion: As a valuable medicinal output derivable from organic waste product that could be converted to wealth, African black soap production, utilisation and commercialisation have tremendous economic potentials. These soaps showed significant antibacterial activity greater than those of the medicated soaps. Hence, their use could be a better option in place of commercially available medicated and antiseptic soaps because of the degree of antibacterial activities they exhibited.


2021 ◽  
Author(s):  
Amalanathan.M ◽  
Aravind.M ◽  
Sony Michael Mary.M ◽  
Razan A. Alshgari ◽  
Asma A. Alothman ◽  
...  

Abstract In this work, jasmine flower derived activated carbon were successfully synthesized by hydrothermal carbonization process at the different annealing temperature. The Crystallinity, phase, structural, morphological and optical properties of activated carbon were investigated using X-ray diffraction (XRD), Fourier Transform Infrared spectroscopy (FT-IR), Scanning electron microscopy (SEM), Transmission electron microscope (TEM), and UV-visible spectroscopy analysis. The graphitic phase of carbon was obtained from the XRD pattern. Surface morphology reveals irregular-shaped nanoparticles. The photodegradation of methylene blue (MB) was carried out under the visible light irradiation technique to study its photocatalytic activity. The activated carbon obtained at 400oC, 500oC and 600oC shows a photocatalytic degradation efficiency of 86%, 90%, and 94%, respectively. Antibacterial activity of activated carbon was examined against S. Aureus (MTCC-737) and E-Coli (MTCC- 443) microbial pathogens, and their potent antibacterial activity was examined from the zone of inhibition layer.


Author(s):  
Shyla Marjorie Haqq ◽  
Amit Chattree

  This review is based on the synthesis of silver nanoparticles (AgNPs) using a green approach which is biofabricated from various medicinal plants. AgNPs were prepared from the various parts of the plants such as the flowers, stems, leaves, and fruits. Various physiochemical characterizations were performed using the ultraviolet (UV)-visible spectroscopy, Fourier transform infrared spectroscopy, X-ray diffraction spectroscopy, transmission electron microscopy, and energy dispersive spectroscopy. AgNPs were also used to inhibit the growth of bacterial pathogens and were found to be effective against both the Gram-positive and Gram-negative bacteria. For the silver to have antimicrobial properties, it must be present in the ionized form. All the forms of silver-containing compounds with the observed antimicrobial properties are in one way or another source of silver ions. Although the antimicrobial properties of silver have been known, it is thought that the silver atoms bind to the thiol groups in enzymes and subsequently leads to the deactivation of enzymes. For the silver to have antimicrobial properties, it must be present in the ionized form. The study suggested that the action of the AgNPs on the microbial cells resulted into cell lysis and DNA damage. AgNPs have proved their candidature as a potential antibacterial against the multidrug-resistant microbes. The biological agents for synthesizing AgNPs cover compounds produced naturally in microbes and plants. Reaction parameters under which the AgNPs were being synthesized hold prominent impact on their size, shape, and application. Silver nanoparticle synthesis and their application are summarized and critically discussed in this review.


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