Antibacterial Activity Of Nanoparticles Research Articles

Green synthesis of anisotropic gold nanoparticles using cinnamon with superior antibacterial activity

Stable gold nanoparticles have been synthesized by one step, cost effective and environment friendly technique at room temperature using the natural spice cinnamon. The synthesized nanoparticles have been characterized using Ultraviolet visible spectroscopy, x-ray diffraction, Fourier transform infrared spectroscopy and Transmission electron microscopy. Transmission electron microscopy images confirm the presence of spherical and anisotropic nanoparticles of different shapes that include triangular, hexagonal and some spherical shaped nanoparticles. The decreased symmetry of anisotropic nanoparticle gives rise to unique optical properties. The antibacterial activity of nanoparticles has also been studied.

Recent advance in antibacterial activity of nanoparticles contained polyurethane

ABSTRACTPolyurethanes (PUs) are among the most widely used polymers with various applications in several industries. Antibacterial activity is an important feature of PU materials used in medical or many other related consumer products. They can, however, be easily colonized by bacteria and fungi, which may cause many problems for human health. It is therefore very important to enhance the antimicrobial properties of PUs, besides improving their chemical and physical properties. The incorporation of some antibacterial materials in the PUs' polymeric matrices is an effective strategy to improve their antibacterial activity. In this regard, the addition of some materials including Ag, Au, ZnO, and TiO2 nanoparticles, carbon nanotubes and chitosan to the PUs' material structure is reviewed in this article, and their antibacterial mechanisms are discussed. © 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019, 136, 46997.

Non-toxic properties of TiO2 and STiO2 nanocomposite PES ultrafiltration membranes for application in membrane-based environmental biotechnology

In membrane bioreactor (MBR) technology, nanocomposite membrane has a great potential to improve the filtration performance and antifouling. However, antibacterial activity of nanoparticles (NPs) is a significant disadvantage which can be impacted to bacterial growth and microbial community in MBRs. The modified polyethersulfone (PES) ultrafiltration (UF) membranes in the study were prepared by using TiO2 NPs and TiO2 NPs functionalized with sulfonation (STiO2). The antibacterial effect of NPs and non-toxic properties of nanocomposite membranes were examined by using three different Gram-negative bacterial species isolated from a local full scale membrane bioreactor treating municipal wastewater (Escherichia coli, Pantoea agglomerans, and Pseudomonas graminis). Results are revealed that the TiO2 and STiO2 NPs have 60% of antibacterial activity based on disc diffusion, viability tests, and TEM analysis. However, the PES-TiO2 and PES-STiO2 nanocomposite UF membranes showed significantly lower antibacterial activity (<95%, significance at p < 0.0001), indicating innocuous to bacterial growth. This study highlights that the PES-TiO2 and PES-STiO2 nanocomposite membrane is more sustainable than PES membrane and promising materials for MBRs, by taking advantage of non-toxic properties to bacterial growth.

Photocatalytic antibacterial activity of copper-based nanoparticles under visible light illumination

Copper oxide and sulfide nanoparticles after annealing treatment at 400 °Chave been characterized and tested for their bactericidal properties toward Staphylococcus aureus and Escherichia coli under the dark and LED light illuminated conditions. It was found that the nanoparticles with the formation of CuS/Cu2S/CuO nanoheterostructuresexhibited a great capability of killing Staphylococcus aureus and Escherichia coli with or without light illumination. The antibacterial activity of the nanoparticles was demonstrated and simply observed with colony counting method. A mechanism of the antibacterial behaviour had been proposed and elucidated in this work.

Size-dependent Bacterial Growth Inhibition and Antibacterial Activity of Ag-doped ZnO Nanoparticles under Different Atmospheric Conditions

Silver is commonly used antibacterial material, and showed improved results when doped to less expensive ZnO nanoparticles. Chemical reduction method with zinc acetate as host and silver nitrate as dopant precursor was used. The surface area of particles was enhanced by calcination in different atmospheric conditions. Antibacterial activity of synthesized nanoparticles was evaluated against different Gram-negative and Gram-positive bacterial strains. Minimum inhibitory (6 to 21 mM) and minimum bactericidal concentrations (23 to 47 mM) indicated that antibacterial activity of nanoparticles was increased by silver doping and calcination in oxygen atmosphere. The X-ray diffraction, scanning electron microscopy and energy dispersive X-ray spectroscopic data further confirmed the hypothesis. Present study confirmed that oxygen treated silver doped zinc oxide nanoparticles could have pharmacological applications as alternative for antibiotics and disinfectants.

Antibacterial activity of nickel and nickel hydroxide nanoparticles against multidrug resistance K. pneumonia and E. coli isolated urinary tract

Objective(s): Antibacterial materials are so significant in the textile industry, water disinfection, medicine, and food packaging. Unfortunately, organic compounds for sterilization show toxicity to the human body; therefore, the interest in inorganic disinfectants such as metal oxide nanoparticles (NPs) is increasing. Materials and Methods: Nickel and nickel hydroxide nanoparticles (NiNPs and Ni(OH)2-NPs) were prepared and characterized by DLS, SEM, AFM and ATR. Antibacterial activity assay was carried by Spot on lawn method against two selected standard pathogenic bacteria such as E. coli (as Gram negative), S. aureus (as Gram positive) and multidrug resistance K. pneumonia and E. coli. Also the minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) were determined against two selected standard pathogenic bacteria and multidrug resistance K. pneumonia and E. coli. Results: The formation of the NiNPs and Ni(OH)2-NPs were confirmed by DLS, SEM, AFM and ATR. Antibacterial activity of nanoparticles were confirmed against two selected standard pathogenic bacteria such as E. coli and S. aureus. And also, NiNPs and Ni(OH)2-NPs revealed fair antibacterial effect against multidrug resistance K. pneumonia and E. coli based on MIC and MBC data. As well, the experimental data presented that the antibacterial activity of NiNPs was more than Ni(OH)2-NPs. Conclusion: Based on the achieved results, NiNPs and Ni(OH)2-NPs show antibacterial activity against clinical patients bacteria (multidrug resistance K. pneumonia and E. coli(. Finally, the NPs evaluated in this study have promising properties for applications as antiseptic agent for environment; however, further studies are warranted such as study toxicity NPs on normal human cell line and other clinical bacteria.

Antibacterial activity of zinc oxide nanoparticles obtained by pulsed laser ablation in water and air

The paper studies physicochemical and antibacterial properties of ZnO nanoparticles obtained by pulsed laser ablation in water and air. Their composition and structure were studied by X-ray diffraction, transmission and scanning electron microscopy. Antibacterial activity of the nanoparticles was examined by its affection on Gram-positive Staphylococcus aureus (S.aureus). The dependence of nanoparticles’ physical and chemical antibacterial properties on the conditions of the ablation was shown. The model materials for the antibacterial bandage were made of cotton, filter paper and biodegradable polymer scaffolds (poly-l-lactide acid), and then they were coated with the obtained ZnO nanoparticles. The model bandage materials were examined by the scanning electron microscopy method and their antibacterial activity (ISO 20743:2013) was determined. High activity of all the samples against S.aureus was proved.

Antibacterial activity of plant extract and zinc nanoparticles obtained from Syzigium aromaticum L.

Nanotechnology deals with the use of nanoparticles in various remarkable fields of present time with vast medicinal, agricultural and industrial applications. Biological approaches using microorganisms and plants or plant extracts for metal nanoparticles, have been suggested as valuable alternatives to chemical methods. In present study Syzigium aromaticum L. extracts in water and ethanol were used for the green synthesis of zinc oxide nanoparticles. After being treated with zinc sulphate solution, the color of all the extracts of plant changed indicating the formation of zinc nanoparticles and their color change was also monitored by using Ultraviolet-Visible spectroscopy. Particle size analyzer showed 44.4 nm for water extract nanoparticles and 103nm for ethanolic NPs. Antibacterial activity of these nanoparticles was evaluated against four bacterial strains, namely Klebsiella pneumonia, Pseudomonas aureginosa, Escherichia coli and Acetobactor bauminii. The zinc oxide nanoparticles of S. aromaticum developed by ethanolic extract did not show the significant antibacterial activity against any bacterial strain. The zinc nanoparticles of S. aromaticum developed by water extract showed maximum inhibition zone against K. pneumonia as 1.43mm, P. aureginosa is 1.00mm, E. coli as 2.14mm and against A. bauminii as 2.30mm as compared to 1.15mm, 1.86mm, 1.76mm and 1.53mm respectively by plant extract. Keywords: Antimicrobial activity; Green nanotechnology; Microwave assisted extraction (MAE); Plant extract; Ultraviolet-visible spectroscopy (UV-Vis); Zinc nanoparticles http://dx.doi.org/10.19045/bspab.2017.600115

Iron, copper and silver nanoparticles: Green synthesis using green and black tea leaves extracts and evaluation of antibacterial, antifungal and aflatoxin B1 adsorption activity

The present study was aimed to account an eco-friendly synthesis of iron (Fe), copper (Cu) and silver (Ag) nanoparticles (NPs) using green tea and black tea leaves extracts. Synthesized NPs were characterized using SEM, FTIR, EDX and UV/Vis spectroscopy techniques. Antibacterial activity of NPs was assessed against methicillin- and vancomycin-resistance Staphylococcus aureus strains. Antifungal activity was investigated against Aspergillus flavus and A. parasiticus fungal species. Adsorbent capability with aflatoxin B1 (AFB1) was also assessed in solution. Ag-NPs showed superior antibacterial/antifungal activities and reduced the aflatoxins production in comparison to Fe-NPs and Cu-NPs. Adsorption capability of all NPs with AFB1 contamination was found in the order of Fe-NPs > Cu-NPs > Ag-NPs. The equilibrium data showed the favorability of Langmuir isotherm with the adsorption capacity (131–139 ng/mg), Cu-NPs (114–118 ng/mg) and Ag-NPs (110–115 ng/mg). Thermodynamic parameters and kinetic studies revealed that adsorption process is spontaneous, endothermic and followed the pseudo-second order. These results suggest that the synthesized NPs could be effectively utilize as an alternative antibacterial/antifungal agent against diseases caused by multiple drug resistant pathogens. In addition, these metal NPs may be utilize as a possible aflatoxins adsorbent in human food and animal feed such as rice, wheat, maize, red chillies and poultry feed.

Mycosynthesis of bactericidal silver and polymorphic gold nanoparticles: physicochemical variation effects and mechanism.

Extracellular synthesis of silver and gold nanoparticles using aqueous cell-free filtrate (CFF) of endophytic Chaetomium globosum and characterization of its bioactive proteins. Temperature and pH gradients were used to assess their effects on dimensions of NPs. NPs were tested in vivo for antibacterial activity. MALDI-TOF-MS/MS was used for characterization of CFF proteins. Fungal CFF fabricated nanoparticles of various shape under varied physicochemical conditions. Silver nanoparticles showed significantly (p≤0.5) enhanced antibacterial activity against Staphylococcus aureus and Klebsiella pneumoniae compared with AgNO3. Two prominent CFF proteins showed homology with benzoate 4-monooxygenase cytochrome P450 and ubiquinol-cytochrome c reductase. The study achieved controlled mycosynthesis of NPs and explains the hitherto poorly known mechanism of reduction, stabilization and antibacterial activity of nanoparticles.

Antibacterial Activity of Nanoparticles Produced by Ethanol Extract of Boesenbergia rotunda Rhizome Loaded with Chitosan and Alginic Acid Against Streptococcus mutans by In Vitro

The antibacterial activity of three Cupressaceae plants (Thujaoccidentalis,ThujaorientalisandChamaecyparisobtusa) was tested against three bacteria using the agar diffusion method. The ether and ethylacetate fraction of crude methanol extract from the three plants showed potent antibacterial activity against the tested microorganisms. The result showed that Staphylococcus aureus revealed the most sensitivity among the tested bacteria. Thujaoccidentalisether fraction and Thujaorientalis hexane fraction exhibited the highest antibacterial activity against Staphylococcus aureus. E. coli was shown the highest MIC values compared to the other two tested bacteria, which indicates the lowest antibacterial activity against the bacterium. This study promises an interesting future for designing a potentially active antibacterial agent from the three Cupressaceae plants.

Facile synthesis of heterostructured cerium oxide/yttrium oxide nanocomposite in UV light induced photocatalytic degradation and catalytic reduction: Synergistic effect of antimicrobial studies

Ceria (CeO2) is an exciting alternative noble metal catalyst, because it has ability to release and absorb oxygen in the redox system, and function as an oxygen buffer. In this study, heterostructured catalysts consisting of CeO2/Y2O3 nanocomposites were successfully synthesized by hydrothermal method in the presence of sodium hydroxide as a reducing agent from cerium nitrate and yttrium nitrate as a precursor which was then evaluated for its photocatalytic activity in the degradation of Rhodamine B (RhB) synthetic dye. Scanning electron microscopy (SEM) imparts the surface morphology and size of the prepared sample. Elemental compositions and the purity of the nanoparticles are proved by energy dispersive X-ray Spectroscopy (EDX). CeO2/Y2O3 nanoparticles were made up of CeO and YO bonds which are confirmed by Fourier transform infrared spectroscopy (FTIR). Synthesis temperature and pressure, during hydrothermal reactions, plays a critical role in controlling the shape, size, oxygen vacancy concentration, and low temperature reducibility in CeO2 based nanocomposites. The lattice constants and oxygen vacancy concentrations of ceria nanoparticles also depend upon the concentration of hydroxide ion which leads to better morphology at low temperature and pressure. Hydrogenation of p-nitrophenol to p-aminophenol with a reducing agent is conveniently carried out in aqueous medium by using this binary metal oxide catalyst. Further, the photocatalytic performance of the synthesized nanoparticles was monitored by photocatalytic degradation of Rhodamine B synthetic dye under UV light irradiation. To get maximum photocatalytic degradation (PCD) efficiency, we have used H2O2 for the generation of excess reactive oxygen species (ROS). In addition, the antibacterial activity of nanoparticles against bacteria was also examined. The observed antibacterial activity results are comparable with the results obtained using the standard antibiotic.

Antibacterial Activities of Nanoparticles of Titanium dioxide, Intrinsic and Doped With Indium and Iron

Antibacterial Activities of Nanoparticles of Titanium dioxide, Intrinsic and Doped With Indium and Iron

Biogenic nanoparticles bearing antibacterial activity and their synergistic effect with broad spectrum antibiotics: Emerging strategy to combat drug resistant pathogens

The present study emphasizes on synthesis of bimetallic silver–gold nanoparticles from cell free supernatant of Pseudomonas veronii strain AS41G inhabiting Annona squamosa L. The synthesized nanoparticles were characterized using hyphenated techniques with UV–Visible spectra ascertained absorbance peak between 400 and 800nm. Possible interaction of biomolecules in mediating and stabilization of nanoparticles was depicted with Fourier transform infrared spectroscopy (FTIR). X-ray diffraction (XRD) displayed Bragg’s peak conferring the 100, 111, 200, and 220 facets of the face centered cubic symmetry of nanoparticles suggesting that these nanoparticles were crystalline in nature. Size and shape of the nanoparticles were determined using Transmission electron microscopy (TEM) microgram with size ranging from 5 to 50nm forming myriad shapes. Antibacterial activity of nanoparticles against significant human pathogens was conferred with well diffusion assay and its synergistic effect with standard antibiotics revealed 87.5% fold increased activity with antibiotic “bacitracin” against bacitracin resistant strains Bacillus subtilis, Escherichia coli and Klebsiella pneumoniae followed by kanamycin with 18.5%, gentamicin with 11.15%, streptomycin with 10%, erythromycin with 9.7% and chloramphenicol with 9.4%. Thus the study concludes with biogenic and ecofriendly route for synthesizing nanoparticles with antibacterial activity against drug resistant pathogens and attributes growing interest on endophytes as an emerging source for synthesis of nanoparticles.

Reactive oxygen species mediated bacterial biofilm inhibition via zinc oxide nanoparticles and their statistical determination.

The formation of bacterial biofilm is a major challenge in clinical applications. The main aim of this study is to describe the synthesis, characterization and biocidal potential of zinc oxide nanoparticles (NPs) against bacterial strain Pseudomonas aeruginosa. These nanoparticles were synthesized via soft chemical solution process in a very short time and their structural properties have been investigated in detail by using X-ray diffraction and transmission electron microscopy measurements. In this work, the potential of synthesized ZnO-NPs (∼10–15 nm) has been assessed in-vitro inhibition of bacteria and the formation of their biofilms was observed using the tissue culture plate assays. The crystal violet staining on biofilm formation and its optical density revealed the effect on biofilm inhibition. The NPs at a concentration of 100 µg/mL significantly inhibited the growth of bacteria and biofilm formation. The biofilm inhibition by ZnO-NPs was also confirmed via bio-transmission electron microscopy (Bio-TEM). The Bio-TEM analysis of ZnO-NPs treated bacteria confirmed the deformation and damage of cells. The bacterial growth in presence of NPs concluded the bactericidal ability of NPs in a concentration dependent manner. It has been speculated that the antibacterial activity of NPs as a surface coating material, could be a feasible approach for controlling the pathogens. Additionally, the obtained bacterial solution data is also in agreement with the results from statistical analytical methods.

Bacteriolysis by vancomycin-conjugated acryl nanoparticles and morphological component analysis

Nanoparticles are currently attracting considerable attention because of their ability to conjugate to various substances. As such, these nanoparticles can assist the transfer of the conjugated substance to target tissues where they are gradually released. In this study, vancomycin-conjugated nanoparticles (VCM NPs) were prepared. The antibacterial activity of VCM NPs was compared with that of VCM alone by exposure to vancomycin-resistant enterococci (VRE). The morphology of the cells was then analyzed by electron microscopy. VCM NPs were found to have more potent antibacterial activity against VRE compared to VCM alone, but the activity against vancomycin-sensitive enterococci (VSE) remained the same. The antibacterial activity of nanoparticles alone was the same against VSE and VRE. The nanoparticles were found to induce characteristic morphological changes in the bacteria based on scanning and transmission electron microscopy. The results suggest that the strong antibacterial activity of VCM NPs against VRE may be attributable not only to the well-known control release carrier property of the nanoparticles but to an additional mechanism that involves VCM NPs avoiding the drug resistant mechanism of VRE.

Antibacterial Activity of Polymer Coated Cerium Oxide Nanoparticles

Cerium oxide nanoparticles have found numerous applications in the biomedical industry due to their strong antioxidant properties. In the current study, we report the influence of nine different physical and chemical parameters: pH, aeration and, concentrations of MgSO4, CaCl2, KCl, natural organic matter, fructose, nanoparticles and Escherichia coli, on the antibacterial activity of dextran coated cerium oxide nanoparticles. A least-squares quadratic regression model was developed to understand the collective influence of the tested parameters on the anti-bacterial activity and subsequently a computer-based, interactive visualization tool was developed. The visualization allows us to elucidate the effect of each of the parameters in combination with other parameters, on the antibacterial activity of nanoparticles. The results indicate that the toxicity of CeO2 NPs depend on the physical and chemical environment; and in a majority of the possible combinations of the nine parameters, non-lethal to the bacteria. In fact, the cerium oxide nanoparticles can decrease the anti-bacterial activity exerted by magnesium and potassium salts.

Mechanism of Photogenerated Reactive Oxygen Species and Correlation with the Antibacterial Properties of Engineered Metal-Oxide Nanoparticles

Oxidative stress induced by reactive oxygen species (ROS) is one of the most important antibacterial mechanisms of engineered nanoparticles (NPs). To elucidate the ROS generation mechanisms, we investigated the ROS production kinetics of seven selected metal-oxide NPs and their bulk counterparts under UV irradiation (365 nm). The results show that different metal oxides had distinct photogenerated ROS kinetics. Particularly, TiO(2) nanoparticles and ZnO nanoparticles generated three types of ROS (superoxide radical, hydroxyl radical, and singlet oxygen), whereas other metal oxides generated only one or two types or did not generate any type of ROS. Moreover, NPs yielded more ROS than their bulk counterparts likely due to larger surface areas of NPs providing more absorption sites for UV irradiation. The ROS generation mechanism was elucidated by comparing the electronic structures (i.e., band edge energy levels) of the metal oxides with the redox potentials of various ROS generation, which correctly interpreted the ROS generation of most metal oxides. To develop a quantitative relationship between oxidative stress and antibacterial activity of NPs, we examined the viability of E. coli cells in aqueous suspensions of NPs under UV irradiation, and a linear correlation was found between the average concentration of total ROS and the bacterial survival rates (R(2) = 0.84). Although some NPs (i.e., ZnO and CuO nanoparticles) released toxic ions that partially contributed to their antibacterial activity, this correlation quantitatively linked ROS production capability of NPs to their antibacterial activity as well as shed light on the applications of metal-oxide NPs as potential antibacterial agents.