Microbial biofilms on biomaterial implants or devices are hard to eliminate by antibiotics due to their protection by exopolymeric substances that embed the organisms in a matrix, impenetrable for most antibiotics and immune-cells. Application of metals in their nanoparticulated form is currently considered to resolve bacterial infections.
Int J Mol Sci. Published online Oct Find articles by Yuping Bao Katrina M. Find articles by Katrina M.
Ramonell Anna Cristina S. Received Jul 24; Accepted Oct 7. This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution license http: This article has been cited by other articles in PMC.
Abstract Increasing use of iron oxide nanoparticles in medicine and environmental remediation has led to concerns regarding exposure of these nanoparticles to the public. However, limited studies are available to evaluate their effects on the environment, in particular on plants and food crops.
Interestingly, the treated plants did not show any observable phenotypic changes in overall size or general plant structure, indicating that environmental nanoparticle contamination could go dangerously unnoticed. Expected production of engineered nanoparticles NPs is projected to reach 58, tons in — [ 45 ].
Engineered NPs are usually divided in four main categories: NPs of 1— nm have attracted the most interest due their unique properties that are not present in corresponding bulk materials [ 789 ] including quantum confinement, a large surface area to volume ratio, high surface energy, and several other catalytic and magnetic properties [ 1011 ].
Controlling the release of engineered NPs into the environment has proven difficult due to the rapid growth of the nanomaterial industry and the usage of nanomaterials in a wide array of products [ 12 ].
Plants are an essential component in ecological systems and may serve as a potential pathway for NP transport into the food chain and a route for bioaccumulation in higher organisms [ 13141516 ]. Many of the reported studies in the literature are focused on silver Ag and titanium oxide TiO2 NPs because of their extensive use in food packing and cosmetics [ 131415161718192021 ].
Most of the current published studies regarding NPs and plants are centered around the effects of NPs on seed germination and vegetative plant growth [ 6 ]. Depending on the types of NPs and the plant species under study, both positive and negative effects have been reported [ 2223242526 ]. The effects observed are highly dependent on the type and concentration of NPs as well as the plant species and growth conditions used in the experiments.
For example, carbon nanotubes were shown to be able to penetrate plant seed coats and dramatically affect both seed germination and plant growth [ 27 ]. TiO2 NPs were reported to improve the growth of spinach by enhancing their photosynthetic rate and nitrogen-fixation capacity in leaves and roots [ 14 ].
In contrast Zinc oxide NPs exhibited inhibitory effects on the germination and growth of plants. Ag NPs, the most prevalent metallic NPs in consumer products, showed no effects on the biomass and transpiration volume of zucchini plants [ 6 ].
However in another study, phytotoxicity of Ag NPs on plant seedling and growth at low concentration was observed and the phytotoxicity was concentration and size dependent [ 14 ]. A developmental phytotoxicity study [ 16 ] indicated that zinc oxide NPs were most phytotoxic, followed by magnetite, silica and alumina NPs, which were not toxic.
Experiments by Lopez-Moreno et al. The authors hypothesized that the observed growth enhancement might be mediated by NP treatment promoting the ability of soybean to absorb water and by enhancement of overall nitrate reductase activity in the plants [ 2829 ].
Additional work by the same group has shown that exposure to CONPs significantly reduced corn, tomato and cucumber germination [ 30 ]. CONPs also significantly inhibited root growth in both alfalfa and tomato but enhanced the root growth in cucumber and corn.
Clearly there is no consensus regarding the effects of a wide variety of NPs on plant growth and development. Upon uptake by plants, NPs can be transported and localize in various tissues. For instance, a significant amount of iron oxide NPs suspended in liquid media were shown to be taken up by pumpkin roots and translocated throughout the plant tissues [ 31 ].
Zinc oxide NPs were reported to pass through the root epidermis and cortex via the apoplastic pathway through cell walls [ 32 ]. Carbon-coated iron NPs injected or sprayed at certain locations on pumpkin leaves were shown to be capable of transport to other locations in the plant [ 33 ].
Detailed microscopic analysis revealed the presence of NPs in pumpkin xylem vessels, a major water transporting tissue in plants [ 33 ]. Another report demonstrated efficient delivery of DNA and chemicals through silica NPs internalized into plant cells [ 34 ].
Even with inconsistent results and unclear mechanisms, it is certain that plants can take up NPs and that NPs can be localized inside plant tissues. Iron oxide nanoparticles IONP are widely used in biomedicine for drug delivery and in magnetic resonance imaging MRI [ 3536373839 ].
These nanoparticles are also widely used for a variety of other applications, such as soil and groundwater treatments [ 40 ] and photocatalytic reactions [ 4142 ]. Iron oxide nanoparticles are also generated from the oxidation of zero-valence iron NPs, which have been used for environmental remediations [ 4344454647 ], with more than 50 commercial sites in the United States [ 48 ].
The increasing commercial use of IONPs has resulted in a concomitant accumulation of them in the environment.
Iron oxides are also present in nature as nano-sized crystals as both maghemite Fe2O3 and magnetite Fe3O4 formed naturally by fire events and volcanism. A major question is how detrimental these higher concentrations of IONPs are to the environment—especially considering that many of these IONPs are coated with biocompatible molecules [ 49 ].
In this study we have investigated the effects of spherical, charged IONPs Fe2O3 nanoparticles on growth, development and seed production in the model plant Arabidopsis thaliana L.Borosilicate Pigments – Transparency Meets Brilliance and Sparkle Authors: Katrin Steinbach Dipl.
Ing., Dr. Ulrich Schmidt, Eckart GmbH, Hartenstein, Germany By the iron oxide coating the golden interference colour effect (new “real gold” effect Mirage Sparkling Luxury Gold – red curve. Charge effect of superparamagnetic iron oxide nanoparticles on The applications of superparamagnetic iron oxide nanoparticles (SPIONs) in various fields have covalent bonds, respectively (Wang et al.
). One study showed that coating SPIONs with a gold layer enabled subsequent functionalization with thiolated DNA, which . Iron oxide nanoparticles were prepared by the thermal decomposition of iron-oleate.
The effect of reaction temperature, time, solvent and surfactant were tested. The synthesized nanoparticles were characterized by XRD, TEM, XPS, TGA and FT-IR.
The results show that reaction time has little effect on. synthesis of iron oxide–gold HNPs (Smolensky et al. ; Zhang et al. ; Ji et al. ; Hoskins et al. b). Previous investigations have shown the use of a polymer ‘cushion’ between the iron oxide core and the gold coating to be advantageous over direct gold .
The Effect of Gold and Iron-Oxide Nanoparticles on Biofilm-Forming Pathogens MadhuBalaSathyanarayanan, 1 RenetaBalachandranath, 1 YuvasriGenjiSrinivasulu, 1 SathishKumarKannaiyan, 2 andGuruprakashSubbiahdoss 1 h of growth in the presence of gold and iron-oxide nanoparticles .mg/mL).
Abstract. Hybrid nanoparticles (HNPs) formed from iron oxide cores and gold nano-shells are becoming increasingly applicable in biomedicine. However, little investigation has been carried out on the effects of the constituent components on their physical characteristics.