Development of a Novel Screening Approach for the Hazard Assessment of Nanoparticles using Both Cell Line Panel and Whole Embryo Analysis
Francesca Baldelli Bombelli, UEA
With the advancement of nanotechnology for a widening spectrum of potential applications it comes an ever increasing risk of unintentional contact with these particles and the associated health and environmental risks of any related exposure. The aim of this proposed project is to develop a toxicity assessment protocol that is suitable for determining the hazard potential of a range of nanoparticle types. All the systems we shall use have the potential to be scaled up for high-throughput assessment that can be utilised for industrial scale toxicity testing in the future. Our overall aim for this project is to develop a standardised protocol for the hazard assessment of nanoparticles.
Nanoparticles and their protein corona
Jens Madsen, University of Southampton
When nanoparticles (NPs) enter a biological fluid, proteins associate with NPs leading to a protein "corona" that largely defines the biological identity of the particle. The aim of the research project is to perform a physico-chemical characterisation of the protein corona formed on a variety of different NPs incubated with lung lavage or isolated human lung cells as a model for NP exposure via the lungs (air pollution). This characterisation is a part of a PhD studentship to understand how the exposure route affects the biological identity of NPs and if this interaction affects the cells subsequent response to infection.
Ecologically relevant nanoparticle coronas and how they influence the particles’ fate and behaviour in artificial and natural freshwater systems
Daniel Read, CEH (NERC), Wallingford
This project investigates the development of eco-coronas for silver nanoparticles (AgNPs) formed from polymeric substances exuded by microbes (naturally and as a stress reaction). Eco-coronas resulting from interactions between AgNPs and microbial organisms may change the particles properties (e.g. dissolution, agglomeration, surface charge & coating) and their bioavailability (uptake & toxicity). Uptake and localisation will be assessed using TEM (and potentially ESEM) imaging of the NP-exposed organisms, and correlated with uptake and 3D imaging using confocal microscopy. The project results will provide major advance on NP-microbes interactions and help explain current mainly observational NP toxicity studies on bacteria and algae.
Uptake and localization of different silver nanoparticles in nematode tissue and potential formation of eco-coronas in an environmentally relevant exposure medium
Claus Svendsen, CEH, Wallingford
This study aims to investigate the fate of silver nanoparticles (AgNPs) with varying properties such as size, surface coating and surface charge and their toxicokinetics in the nematode Caenorhabditis elegans. C. eleganshave been shown to assimilate AgNP, however, little is known about actual routes of uptake and distribution within the organism and particle dependent differences thereof, which we will investigate using TEM and confocal microscopy. Furthermore, we propose to study eco-coronas formed around ingested AgNP and aim to fully relate potential differences in impacts of the various AgNPs to routes of uptake and distribution.
Nanomaterial fate, transport, behaviour and bioavailability in the environment
Teresa Fernandes, Herriot-Watt University
This research aims to assess silver nanoparticle (NP) dynamics (dissolution and aggregation/agglomeration behaviour) under variable water chemistry and fluid flow/turbulence rates in order to explore the environmental fate and behaviour of NPs in the environment. Specifically this project will address:
- How water chemistry and NP surface modifications may affect the behaviour of silver NP;
- How environmentally related factors e.g. pH, sunlight and flow rates/turbulence* may affect silver NP aggregation and dissolution
*flow/turbulence will be generated in a flume, which is designed to be portable and representative of natural systems. This project is undertaken in collaboration with School of Built Environment at Heriot-Watt University where the flume work will take place.
Characterisation of nanometre-sized aluminium sulphates: implications for mobility of aluminium from mine wastes
Karen Hudson-Edwards, University of London
Wastes produced from the mining and extraction of metal, industrial mineral and energy resources constitute one of the largest waste streams on Earth, and they can contain considerable quantities of potentially toxic elements. Aluminium (Al) is one of these elements, whose high concentrations can have severe effects on ecosystems and
humans. The risks posed by exposure to Al are controlled by the reactivity of Al-bearing minerals, which in mine wastes are most commonly the sulphates alunite [KAl3(SO4)2(OH)6] and basaluminite [Al4(OH)10(SO4)⋅4H2O]. In spite of their importance, the rates, mechanisms, products and controls on the dissolution of these Al sulphate minerals in mine waste environments are not well known. Part of the reason their reactivities are poorly understood is likely that they occur as nano-sized particles, which have been poorly studied. In order to bridge this knowledge gap, dissolution experiments using both natural and synthetic alunite and basaluminite are being carried out. Since particle size has been shown to be one of the main controlling factors for the dissolution of minerals, and because nano-sized sulphates occur in the natural environment, it is of paramount importance to conduct the experimental work using both nano- and micro-sized alunite and basaluminite. Before we can conduct these dissolution experiments, however, we need to synthesise and characterise nano-sized alunite and basaluminite, and compare and contrast their properties to their micro-sized equivalents. We are applying to FENAC for the facilities and expertise to carry out this research.
Probing surface hydrophobicity of non-biodegradable, polymeric nanoparticles by AFM
Marie-Christine Jones, University of Birmingham
This pilot project will concentrate on the feasibility of using atomic force microscopy (AFM) to evaluate nanoparticle surface hydrophobicity. Despite being recognised as an important factor for interactions with bio- and ecological systems, surface hydrophobicity is not routinely explored as part of standard nanoparticle characterisation. Here, it is hypothesised that measuring adhesion forces between chemically modified AFM tips and nanoparticles can be used to measure hydrophobicity. Experiments will be conducted on two separate polymeric nanomaterials with known discrepancies in terms of surface properties with the aim to address potential experimental caveats.
Are iron nanoparticles in wet deposition a potential source of bioavailable Fe to marine algae?
Zongbo Shi, University of Birmingham
The iron (Fe) biogeochemical cycle has a critical influence on primary production in large areas of the oceans, and consequently has the potential to impact on climatic change through the fixation of atmospheric carbon by phytoplankton. Iron nanoparticles (FeNPs) are known to occur in rainwater (Shi et al., 2009) as a result of atmospheric processing of mineral dusts, and thus are a potential source of bioavailable Fe in high nitrogen, low carbon (HNLC) areas of the ocean through wet-deposition. This project will investigate the extent to which Fe (ferrihydrite) nanoparticles are bioavailable to a model marine diatom Thalassiosira pseudonana.
The project plan adopts a tiered approach using progressively more environmentally relevant forms of FeNP:
- Laboratory synthesised FeNPs with PVP and humic acid capping agents.
- FeNPs generated from simulated atmospheric processing of mineral dust.
- FeNPs from natural rainwater.
This tiered approach will allow characterisation methods to be optimised with relatively well-defined NPs, prior to characterising less abundant, and less well studied environmentally derived NPs.
Shi, Z. B.; Krom, M. D.; Bonneville, S.; Baker, A. R.; Jickells, T. D.; Benning, L. G., Formation of Iron Nanoparticles and Increase in Iron Reactivity in Mineral Dust during Simulated Cloud Processing. Environmental Science & Technology 2009,43(17), 6592-6596.
Synthesis and characterisation of isotopically labelled labelled Fe oxyhydroxide nanoparticles
Eniko Kadar, Plymouth Marine Laboratory
Atmospheric iron deposition in the form of mineral dust and volcanic ash increases phytoplankton productivity in iron-limited areas of the ocean, with major potential implications on the Earth’s carbon cycle. Despite that, the environmental fate of Fe-rich natural nanoparticles (NPs) derived from atmospheric dust/ash deposition is very poorly understood, partly as these particles are nanosized and technologies for their detection/quantification are only beginning to be available. Based on our recent laboratory simulations [1, 2] we hypothesize that Fe-rich natural nanoparticles (NPs) in the form of oxy-ferrihydrites are chief portion of the bioavailable iron following atmospheric dust/ash deposition, but we do not have accurate figures on the conversion of various types of parental dusts into nanoparticulate material or on which forms of nanoparticulate iron are prevalent upon contact with seawater. We also need a better understanding on how marine organisms might take up and utilise nano forms of Fe.
Here we seek funds to synthesise stable isotopically labelled ferrihydrite nanoparticles (via simulated cloud processing) to be used as model nanoparticles in both cloud processing simulations and microalgal exposure studies in order to fill the knowledge gaps on the biological uptake and consequences of atmospheric dust deposition.
Kadar, E.; Fisher, A.; Stolpe, B.; Calabrese, S.; Lead, J.; Valsami-Jones, E.; Shi, Z., Colloidal stability of nanoparticles derived from simulated cloud-processed mineral dusts. Sci. Total Environ. 2014,466, 864-870.
Kadar, E.; Cunliffe, M.; Fisher, A.; Stolpe, B.; Lead, J.; Shi, Z., Chemical interaction of atmospheric mineral dust-derived nanoparticles with natural seawater - EPS and sunlight-mediated changes. Sci. Total Environ. 2014,468, 265-271.