Azadirachtin a biological compound found in neem have medicinal and pesticidal properties. The present work reports on the encapsulation of neem oil nanoemulsion using sodium alginate (Na-Alg) by cross linking with glutaraldehyde. Starch and polyethylene glycol (PEG) were used as coating agents for smooth surface of beads.
View Article and Find Full Text PDFThis study on a microcosm, brings out the temporal changes in physico-chemical behavior of aluminum oxide nanoparticles (for a period of 210 days), at environmentally relevant concentrations (1000 μg/L and below). The dynamics of particle behavior in terms of mean hydrodynamic diameter, specific surface area and dissolution of soluble aluminum and, their possible ecological implications have been presented in this study. A thorough statistical analysis brings out nanoparticle behavior, where a rapid aggregation of particles (79±13 nm at 0 h to 1464±80 nm at 48 h), with a decrease in specific surface area (32 m2/g at 0 h to 1.
View Article and Find Full Text PDFSilver nanoparticles (AgNPs) are proven to be an effective catalytic material for various applications due to their excellent optical and electronic properties. In this paper, we describe a novel approach for the degradation of starch using the catalytic behaviour of AgNPs in an enzyme catalysed reaction of starch hydrolysis by α-amylase. AgNPs were synthesized by soluble starch reducing silver nitrate to silver atoms.
View Article and Find Full Text PDFSilver nanoparticles (SNPs) are being increasingly used in many consumer products and industrial application. The release of SNPs to the environment is a major concern. Here we have studied the adsorptive removal of SNPs by a SNP resistant bacterial species Aeromonas punctata, isolated from the sewage environment.
View Article and Find Full Text PDFChrome mining activity has contributed intensively towards pollution of hexavalent chromium around Sukinda Valley, Orissa, India. In an attempt to study the specific contribution of exopolysaccharides (EPS) extracted from indigenous isolates towards Cr(VI) reduction, three chromium (VI) tolerant strains were isolated from the effluent mining sludge. Based on the tolerance towards Cr(VI) and EPS production capacity, one of them was selected for further work.
View Article and Find Full Text PDFThe cytotoxicity of Al(2)O(3) nanoparticles (NP) at very low exposure levels (1 μg/mL and less) to a dominant bacterial isolate from freshwater (lake water), Bacillus licheniformis, was examined. Sterile lake water was directly used as a test medium or matrix to simulate the freshwater environment. Exposure to 1 μg/mL Al(2)O(3) NP for 2 h caused a 17% decrease in cell viability (as determined by plate count and MTT assay).
View Article and Find Full Text PDFPresent study deals with the applicability of bacterial biofilms for the bioremoval of trivalent chromium from tannery effluents. A continuous flow reactor was designed for the development of biofilms on different substrates like glass beads, pebbles and coarse sand. The parameters for the continuous flow reactor were 20 ml/min flow rate at 30°C, pH4.
View Article and Find Full Text PDFThe stability of commercial silver nanoparticles (SNPs) in aquatic environment plays a significant role in its toxicity to the environment and to human health. Here, we have studied the impact of bacterial exopolysaccharides (EPS) to the stability of engineered SNPs. When nanoparticles are present in neutral water, the nanoparticles exhibited low zeta potential and are least stable.
View Article and Find Full Text PDFBackground: Nanoemulsion composed of neem oil and non-ionic surfactant Tween 20, with a mean droplet size ranging from 31.03 to 251.43 nm, was formulated for various concentrations of the oil and surfactant.
View Article and Find Full Text PDFIndiscriminate and increased use of silver nanoparticles (SNPs) in consumer products leads to the release of it into the environment. The fate and transport of SNPs in environment remains unknown. We have studied the interaction of SNPs with extracellular protein (ECP) produced by two environmental bacterial species and the adsorption behavior in aqueous solutions.
View Article and Find Full Text PDFWe here in report an extensive study on the development of a highly facile, selective and sensitive colorimetric probe for cysteine detection using silver nanoparticles (Ag NPs). The efficacy of the process relies upon the surface plasmon resonance properties of Ag NPs and the interaction of Ag-cysteine complex with chromium ions (Cr(3+)) in a ratio of 2:1. In the presence of Cr(3+), cysteine was able to induce the aggregation of Ag NPs thereby resulting in a change in yellow colour of the Ag colloid to purple.
View Article and Find Full Text PDFColloids Surf B Biointerfaces
October 2011
Silver nanoparticles (SNPs) are being increasingly used in many consumer products like textile fabrics, cosmetics, washing machines, food and drug products owing to its excellent antimicrobial properties. Here we have studied the adsorption and toxicity of SNPs on bacterial species such as Pseudomonas aeruginosa, Micrococcus luteus, Bacillus subtilis, Bacillus barbaricus and Klebsiella pneumoniae. The influence of zeta potential on the adsorption of SNPs on bacterial cell surface was investigated at acidic, neutral and alkaline pH and with varying salt (NaCl) concentrations (0.
View Article and Find Full Text PDFSilver nanoparticle (SNP) is a threat to soil, water and human health. Protection of environment from silver nanoparticles is a major concern. A sewage isolate, Bacillus pumilus treated with SNPs showed similar growth kinetics to that without nanoparticles.
View Article and Find Full Text PDFIncreasing use of zinc oxide nanoparticles (ZnO NP) in consumer products may enhance its release into the environment. Phytotoxicity study is important to understand its possible environmental impact. Allium cepa (Onion bulb) is the best model organism to study genetic toxicology of nanoparticles.
View Article and Find Full Text PDFIn view of their increasing commercial applications metal oxide NPs like titania have elevated chances of entry to the environment. The ecotoxicity analyses are required to assess their environmental risks. The present work aims to demonstrate the effect of titania NPs on microalgae isolated from freshwater environment (Scenedesmus sp.
View Article and Find Full Text PDFThe effluents from tanning industries in and around Palar river basin are the major cause of Cr (III) pollution. Forty-five chromium (III) tolerant bacterial strains were isolated from the Palar river basin. Bacillus subtilis VITSCCr01 showed tolerance up to 1500 mg/l and its Cr (III) bioremoval capacity was 64%.
View Article and Find Full Text PDFUse of silver nanoparticles (SNPs) is increasing in a large number of consumer products. Thus, the possible build-up of the nanoparticles in the environment is becoming a major concern. Aeromonas punctata isolated from sewage showed tolerance to 200 μg/ml SNPs.
View Article and Find Full Text PDFEcotoxicol Environ Saf
November 2010
The formulation of water dispersible nanopermethrin was investigated for its larvicidal property. Nanopermethrin was prepared using solvent evaporation of oil in water microemulsion, which was obtained by mixing an organic and aqueous phase. The mean particle size of nanodispersion in water was 151 ± 27 nm.
View Article and Find Full Text PDFIn the present study, silver nanoparticles were rapidly synthesized at room temperature by treating silver ions with the Citrus limon (lemon) extract. The effect of various process parameters like the reductant concentration, mixing ratio of the reactants and the concentration of silver nitrate were studied in detail. In the standardized process, 10(-2)M silver nitrate solution was interacted for 4h with lemon juice (2% citric acid concentration and 0.
View Article and Find Full Text PDFSilver nanoparticles are known to have bactericidal effects. A new generation of dressings incorporating antimicrobial agents like silver nanoparticles is being formulated to reduce or prevent infections. The particles can be incorporated in materials and cloth rendering them sterile.
View Article and Find Full Text PDFColloids Surf B Biointerfaces
March 2010
Biofunctionalization of noble metal nanoparticles like Ag, Au is essential to obtain biocompatibility for specific biomedical applications. Silver nanoparticles are being increasingly used in bio-sensing applications owing to excellent optoelectronic properties. Among the serum albumins, the most abundant proteins in plasma, a wide range of physiological functions of Bovine Serum Albumin (BSA) has made it a model system for biofunctionalization.
View Article and Find Full Text PDFPotential health and environmental effects of nanoparticles need to be thoroughly assessed before their widespread commercialization. Though there are few studies on cytotoxicity of nanoparticles on mammalian and human cell lines, there are hardly any reports on genotoxic and cytotoxic behavior of nanoparticles in plant cells. This study aims to investigate cytotoxic and genotoxic impacts of silver nanoparticles using root tip cells of Allium cepa as an indicator organism.
View Article and Find Full Text PDFUnlabelled: Metal oxide nanoparticles (NPs) are known to possess strong antimicrobial properties. Aluminum oxide NPs have wide-range applications in industrial as well as personal care products. In the absence of prior reports on the antimicrobial properties of alumina NPs for a wide concentration range, the principal objective of the present work was to study the growth-inhibitory effect of alumina NPs over a wide concentration range (10-1000 microg/mL) on an environmentally relevant gram-negative model microorganism, Escherichia coli.
View Article and Find Full Text PDFFor many applications ranging from catalysis to sensors to energetic materials, it is desirable to produce intimate mixtures of nanoparticles. For instance, to improve the reaction rates of energetic materials, the oxidizing agent and the fuel need to be mixed as intimately as possible, ideally at the nanoscopic level. In this context, the acidity of a hydrated CuCl(2) solution reacting toward a network of CuO nanoparticles (a good oxidant) is used to induce one-pot cogelation of a nanostructured network of a resorcinol-formaldehyde resin (RF, the fuel).
View Article and Find Full Text PDFThe serotonin1A (5-HT1A) receptor is an important member of the superfamily of seven transmembrane domain G-protein coupled receptors (GPCRs). We report here that guanine nucleotide sensitivity of agonist binding to hippocampal 5-HT1A receptors is dependent on the concentration of Mg2+. Our results show that agonist binding to 5-HT1A receptors is relatively insensitive to guanine nucleotides in the absence of Mg2+.
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