Synthesis Of ZnO NPs Research Articles

A review on green synthesis of zinc oxide nanoparticles – An eco-friendly approach

Abstract Nanotechnology deals with the production and usage of material with nanoscale dimension. Nanoscale dimension provides nanoparticles a large surface area to volume ratio and thus very specific properties. Zinc oxide nanoparticles (ZnO NPs) had been in recent studies due to its large bandwidth and high exciton binding energy and it has potential applications like antibacterial, antifungal, anti-diabetic, anti-inflammatory, wound healing, antioxidant and optic properties. Due to the large rate of toxic chemicals and extreme environment employed in the physical and chemical production of these NPs, green methods employing the use of plants, fungus, bacteria, and algae have been adopted. This review is a comprehensive study of the synthesis and characterization methods used for the green synthesis of ZnO NPs using different biological sources.

ZnO nanoparticles (ZnO-NPs) and their antifungal activity against coffee fungus Erythricium salmonicolor

In this work, a methodology of synthesis was designed to obtain ZnO nanoparticles (ZnO NPs) in a controlled and reproducible manner. The nanoparticles obtained were characterized using infrared spectroscopy, X-ray diffraction, and transmission electron microscopy (TEM). Also, we determined the antifungal capacity in vitro of zinc oxide nanoparticles synthesized, examining their action on Erythricium salmonicolor fungy causal of pink disease. To determine the effect of the quantity of zinc precursor used during ZnO NPs synthesis on the antifungal capacity, 0.1 and 0.15 M concentrations of zinc acetate were examined. To study the inactivation of the mycelial growth of the fungus, different concentrations of ZnO NPs of the two types of synthesized samples were used. The inhibitory effect on the growth of the fungus was determined by measuring the growth area as a function of time. The morphological change was observed with high-resolution optical microscopy (HROM), while TEM was used to observe changes in its ultrastructure. The results showed that a concentration of 9 mmol L−1 for the sample obtained from the 0.15 M and at 12 mmol L−1 for the 0.1 M system significantly inhibited growth of E. salmonicolor. In the HROM images a deformation was observed in the growth pattern: notable thinning of the fibers of the hyphae and a clumping tendency. The TEM images showed a liquefaction of the cytoplasmic content, making it less electron-dense, with the presence of a number of vacuoles and significant detachment of the cell wall.

Stabilization of nano-structured ZnO particles onto the surface of cotton fibers using different surfactants and their antimicrobial activity

ZnO NPs were prepared and deposited onto cotton fibers via ultrasound irradiation successfully. Different surfactants (SDS, HY, CTAB, TX-100) have been used to stabilize, homogenize the coated ZnO NPs and control their shape and size as encapsulated species. The use of surfactants has improved the durability of ZnO NPs and decreased its leaching in particular SDS. The small mean crystallite size for ZnO particles due to the use of surfactants is the main reason for decreasing the leached of ZnO particles from cotton substrate. SEM and XRD analysis revealed information about the shape and size of the coated ZnO nanoparticles. The use of SDS and HY surfactants in the synthesis of ZnO NPs coated fabrics showed the highest antibacterial and antifungal activities against different pathogenic bacterial and fungal species with high reduction reached over 90%.

Antibacterial Activity of ZnO Nanoparticle Coated Textiles Against Staphylococcus Aureus

Health and hygiene is the indispensable thing with maximum efficiency to human beings. Infections are cause by tiny things (organisms) that get into the human body to start multiplying and the immune system can’t fight them off immediately. Some organisms are harmless and help human bodies to work properly and some bacteria are that causes infections. Staphylococcus aureus is the most common skin affected bacteria. Staph skin infections are common, particularly among children, teenagers, young adults and even healthy people but more serious infections tent to affect those who have a weakened immune system because of an underlying medical condition or a side effect of treatment, skin, deep wound or major burn such as chemotherapy. The textiles used for the hospital purpose are contact with bad bacteria and cause the illnesses and death. So the effective antimicrobial finish has been essential for the safeguard of human beings from harmful microorganism to prevent them from cross infection. ZnO- NPs exhibit attractive antibacterial properties. This paper focus on the antimicrobial activity on 100% Cotton 40 s count fabric with natural and synthetic dye using hospital usable colours, such as Green and blue. ZnO-NPs synthesis was done by wet chemical method using ethanol medium with 1:1 concentrations with pH 12 using optimizing temperature 60, 70, 80, 90˚ C. The ZnO nanoparticles characterization was analysed by XRD, SEM/EDAX, FTIR, UV absorption. Higher zone inhibition (ZE4) was selected for further textile coating process and evaluated the activity on against staphylococcus aureus. ZE4 coated green and Blue Vat fabrics has 20 mm, 22 mm Zone than ZE4 coated Eclipta, Indigo fabrics 18 mm,19 mm.

Photocatalytic degradation of Congo red using Carissa edulis extract capped zinc oxide nanoparticles

The use of plant extract to synthesize nanoparticle has been considered as one of the eco-friendly method. Additionally, it is a strong alternate for conventional methods which includes chemical and physical approach. In this study, microwave assisted extraction of Carissa edulis (C. edulis) at 70°C and 400W was used to extract the secondary metabolites. Further, the metabolites were used as capping agent and Zn (NO3)2 as the metal precursor to synthesize ZnO nanoparticles (ZnO NPs). UV–Vis spectroscopy, FT-IR, XRD, SEM and HR-TEM were used for the characterization of nanoparticles. The Surface Plasmon Resonance around 358nm from the UV–Vis spectroscopy result represents the ZnO NPs formation. The FT-IR confirms the presence of functional groups that acts as the capping agent for the synthesis of ZnO NPs. The crystalline structure of nanoparticles is revealed in the XRD result, morphology showed by SEM results and the size of the ZnO NPs were predicted by HR-TEM. We have carried out the photocatalytic degradation of Congo red at 365nm in photo reactor using ZnO NPs. The result from the photocatalytic degradation Congo red showed rate constant is (−k) 0.4947 with 97% of degradation. This is our first attempt on the C. edulis extract on ZnO NPs preparation and Congo red dye degradation revels that ZnO NPs exhibit good photocatalytic property.

Green synthesis of nano zinc oxide and evaluation of its impact on germination and metabolic activity of Solanum lycopersicum

In the present study, zinc oxide nanoparticles (ZnO NPs) were rapidly synthesized at room temperature by treating zinc acetate dihydrate with the flower extract of Elaeagnus angustifolia (Russian olive). The formation of ZnO NPs was primarily confirmed by UV–visible absorption spectrum in the range of 250–700nm. XRD analysis and DLS particle size analyzer revealed the size of ZnO NPs. The FTIR spectrum revealed the presence of phytochemicals in the flower extract mediated ZnO NPs. Moreover, the morphology of the ZnO NPs was determined using SEM. Seeds of Solanum lycopersicum (tomato) were separately treated with different concentrations of synthesized ZnO NPs and zinc sulphate (ZnSO4) salt suspensions (common zinc supplement). The effect of these treatments on seed germination, seedling vigor, chlorophyll, protein and sugar contents as well as on the activities of lipid peroxidation and antioxidant enzyme were studied. Leaves of plants treated with 6.1mM concentration of ZnO NPs recorded maximum reflectance while it was minimum in plants treated with 1.2mM concentration of NPs. The effect of synthesized ZnO NPs on seedling vigor, pigment, protein and sugar content was found affirmative at lower concentrations contrary to control and ZnSO4 salt. The inhibitory effect at higher concentration of NPs indicated importance in the precise application of NPs, in Zn deficient system, where plant response varies with concentration. To the best of our knowledge this is the first report on Elaeagnus angustifolia mediated synthesis of ZnO NPs and their effects on germination and physiological activity of tomato.

EXTRACELLULAR SYNTHESIS OF ZINC OXIDE NANOPARTICLES USING ACINETOBACTER SCHINDLERI SIZ7 AND ITS ANTIMICROBIAL PROPERTY AGAINST FOODBORNE PATHOGENS

The present study focuses on the microbial synthesis of zinc oxide nanoparticles (ZnO NPs) and evaluating the antimicrobial property on foodborne pathogens. The bacterial strain, Acinetobacter schindleri SIZ7 was isolated from the waste filling area of Sivakasi, Tamil Nadu, India. The biogenic synthesis of ZnO NPs was carried out at room temperature and under suitable, eco-friendly environment using culture supernatant of A. schindleri. The physico-chemical properties exhibited by the biogenic ZnO NPs were characterised using UV-Visible Spectrophotometry, Energy dispersive X-ray spectroscopy (EDS), High Resolution Transmission Electron Microscopy (HRTEM), Fourier Transformed Infrared spectroscopy (FTIR) and Thermogravitometric Analysis (TGA). The synthesized ZnO NPs are polydispersed and spherical in shape. The antimicrobial activity of ZnO NPs was investigated against foodborne pathogens, Staphylococcus aureus (MTCC 96), Escherichia coli (MTCC 739), Vibrio parahaemolyticus (MTCC 451) and Salmonella enterica (MTCC 9844). The prepared ZnO NPs exhibited strong antimicrobial activity against E. coli and S. enterica with a minimum inhibitory concentration of 100µg ml-1. Thus, the bacterial strain Acinetobacter schindleri SIZ7 could be used for simple, extracellular, non-hazardous and efficient synthesis of antimicrobial ZnO NPs.

Durable antibacterial and UV protections of in situ synthesized zinc oxide nanoparticles onto cotton fabrics

Herein we represent a new discovery based on amine material called hexamethyltriethylene tetramine (HMTETA). We have observed that when an aqueous solution of Zn(NO3)·6H2O was added to aqueous solution of HMTETA followed by shaking for a time, the colorless solution was converted to milky color under the alkaline medium provided by HMTETA prior to formation of uniform zinc oxide nanoparticles (ZnO NPs). The latter are in situ formed within the cotton fabrics without the support of capping or other stabilizing agents. Obviously, then, the new made of formation of ZnO NPs speaks of a single-stage process where cotton fabric is immersed in a prepared solution of the new precursors through which binding of ZnO NPs into the textile fabrics takes place. Textile fabrics are, indeed, used as a template, which is capable of maintaining the size and surface distribution of the as-synthesized nanoparticles in a uniform domain. It is also likely that nanoparticles is confined inside the fibril and microfibrils of the cotton fibers. World-class facilities have been employed to follow up the synthesis of ZnO NPs, their characterization and their application to confer, in particular, high durable antibacterial and UV protective function on cotton fabrics.

Potato extract as reducing agent and stabiliser in a facile green one-step synthesis of ZnO nanoparticles

A facile green recipe was developed to synthesise highly pure, safe and durable zinc oxide nanoparticles (ZnO Nps) using homemade starch-rich potato extract. The ZnO Nps were synthesised using zinc nitrate and potato extract, and the whole reaction is carried out for 30 min at 80 °C. In the synthesis, starch-rich potato extract acted as the reducing agent and as a stabilising layer on freshly formed ZnO Nps. Hexagonal (wurtzite) shaped ZnO Nps with size about 20 ± 1.2 nm were synthesised and characterised using X-ray diffraction, transition electron microscope and scanning microscopy analyses. Fourier transform infrared spectral analysis indicated that highly pure ZnO nanopowders were obtained at higher temperatures. The use of environmentally benign and renewable material as the respective reducing and protecting agents, starch-rich potato extract, as well as a gentle solvent medium (H2O), offered a simple and quite efficient procedure for the synthesis of ZnO Nps in neutral medium with promising potential for biological and biomedical applications.

EGCG assisted green synthesis of ZnO nanopowders: Photodegradative, antimicrobial and antioxidant activities

Zinc oxide nanopowders were synthesized by solution combustion method using Epigallocatechin gallate (EGCG) a tea catechin as fuel. The structure and morphology of the product was characterized by Powder X-ray Diffraction, Scanning Electron Microscopy, photoluminescence and UV–Visible spectroscopy. The nanopowders (Nps) were subjected to photocatalytic and biological activities such as antimicrobial and antioxidant studies. PXRD patterns demonstrate that the formed product belongs to hexagonal wurtzite system. SEM images show that the particles are agglomerated to form sponge like structure and the average crystallite sizes were found to be ∼10–20nm. PL spectra exhibit broad and strong peak at 590nm due to the Zn-vacancies, and O-vacancies. The prepared ZnO Nps exhibit excellent photocatalytic activity for the photodegradation of malachite green (MG) and methylene blue (MB) indicating that the ZnO NPs are potential photocatalytic semiconductor materials. ZnO NPs exhibit significant bactericidal activity against Klebsiella aerogenes, Pseudomonas aeruginosa, Escherichia coli and Staphylococcus aureus using the agar well diffusion method. Furthermore, the ZnO nano powders show good antioxidant activity by potentially scavenging DPPH radicals. The study successfully demonstrates synthesis of ZnO NPs by simple ecofriendly route employing EGCG as fuel that exhibit superior photodegradative, antibacterial and antioxidant activities.

X-Ray Analysis by Williamson-Hall and Size-Strain Plot Methods of ZnO Nanoparticles with Fuel Variation

In this paper, a simple and facile surfactant assisted combustion synthesis is reported for the ZnO nanoparticles. The synthesis of ZnO-NPs has been done with the assistance of non-ionic surfactant TWEEN 80. The effect of fuel variations and comparative study of fuel urea and glycine have been studied by using characterization techniques like X-ray diffraction (XRD), transmission electron microscope (TEM) and particle size analyzer. From XRD, it indicates the presence of hexagonal wurtzite structure for ZnO-NPs. Using X-ray broadening, crystallite sizes and lattice strain on the peak broadening of ZnO-NPs were studied by using Williamson-Hall (W-H) analysis and size-strain plot. Strain, stress and energy density parameters were calculated for the XRD peaks of all the samples using (UDM), uniform stress deformation model (USDM), uniform deformation energy density model (UDEDM) and by the size-strain plot method (SSP). The results of mean particle size showed an inter correlation with W-H analysis, SSP, particle analyzer and TEM results.

Zinc oxide nanoparticles for revolutionizing agriculture: synthesis and applications.

Nanotechnology is the most innovative field of 21st century. Extensive research is going on for commercializing nanoproducts throughout the world. Due to their unique properties, nanoparticles have gained considerable importance compared to bulk counterparts. Among other metal nanoparticles, zinc oxide nanoparticles are very much important due to their utilization in gas sensors, biosensors, cosmetics, drug-delivery systems, and so forth. Zinc oxide nanoparticles (ZnO NPs) also have remarkable optical, physical, and antimicrobial properties and therefore have great potential to enhance agriculture. As far as method of formation is concerned, ZnO NPs can be synthesized by several chemical methods such as precipitation method, vapor transport method, and hydrothermal process. The biogenic synthesis of ZnO NPs by using different plant extracts is also common nowadays. This green synthesis is quite safe and ecofriendly compared to chemical synthesis. This paper elaborates the synthesis, properties, and applications of zinc oxide nanoparticles.

<i>In Situ</i> Growth of Zinc Oxide Nanoparticles on Cotton Fabric Using Sonochemical Method

Researches show that properties of semiconductor materials such as electrical, optical and antibacterial properties can be improved in the nanoscale. Among the semiconductor materials , zinc oxide with excellent electronic properties has been considered extremely. Application and properties of Zno nanoparticles depends on the size and morphology. In the present work, Zno Nanoparticles (NPs) were prepared by sonochemical method at a constant temperature and were applied on to the 100% cotton woven fabric using Insitu method. The results show that nanoparticles with average sizes of 20-100 nm with different morphologies were created on the surface of samples. Synthesis of ZnO-NPs were varied in the morphological transformation by changes in zinc acetate concentration. Characterizations were carried out, Scanning electron microscopy (SEM) and Spectrophotometery. The antibacterial activities of the fabrics were assessed semi-quantitatively by the coloneis count method. The results show that the finished fabric demonstrated significant antibacterial activity against S.aureus in antibacterial test.

ROS-dependent anticandidal activity of zinc oxide nanoparticles synthesized by using egg albumen as a biotemplate

Zinc oxide nanoparticles (ZnO NPs) have attracted great attention because of their superior optical properties and wide application in biomedical science. However, little is known about the anticandidal activity of ZnO NPs against Candida albicans (C. albicans). This study was designed to develop the green approach to synthesize ZnO NPs using egg white (denoted as EtZnO NPs) and investigated its possible mechanism of antimicrobial activity against C. albicans 077. It was also notable that anticandidal activity of EtZnO NPs is correlated with reactive oxygen species (ROS) production in a dose dependent manner. Protection of histidine against ROS clearly suggests the implication of ROS in anticandidal activity of EtZnO NPs. This green approach based on egg white-mediated synthesis of ZnO NPs paves the way for developing cost effective, eco-friendly and promising antimicrobial nanomaterial for applications in medicine.

ZnO/Liquid Crystalline Nanohybrids: From Properties in Solution to Anisotropic Growth

Branched thermotropic liquid crystals (LCs) were successfully used as stabilizers for the synthesis of isotropic photoluminescent ZnO nanoparticles (NPs) in solution. (1)H NMR spectroscopy and differential scanning calorimetry experiments demonstrate the existence of specific interactions between the LC and both the ZnO precursor and ZnO NPs. This offers the possibility for some branched molecules to act as structurally ordered hosts for the anisotropic growth of ZnO NPs.