Overview

Project Highlights:

  • Nanomaterials are extensively used in consumer products, with little knowledge and understanding of their long-term effects following their disposal and entry into marine environments.
  • This project will investigate the interaction, fate and ecotoxic effects of common nanomaterials on natural microbial communities.
  • This research has massive potential societal impact and could redefine policy and legislation on the use and disposal of nanomaterials in consumer goods.

The introduction of microplastics into the environment from consumer products, such as facial scrubs, has recently been highlighted as a major marine pollutant with the potential to affect organisms from zooplankton to small fish and larger fauna. The resilient nature of their smaller cousins, nanomaterials, and their unique properties, which are coupled to their small sizes, has made them popular for use in a large range of commercial consumer products, from food additives and cosmetics to catalysts. In our current intense consumer society, these products are rapidly disposed of and end up as waste products – inevitably being washed into rivers and ending up in the oceans. However, little is known about their transformation, impact and eventual fate in such environments.

This research project aims to investigate the behaviour and effect of key metal and metal oxide nanomaterials (including gold, silver, titanium dioxide, zinc oxide, aluminium oxide, iron oxide and copper oxide) commonly found in consumer products (e.g. sunscreens, cosmetics and antibacterial products, Figures 1 & 2) on marine environments and microorganisms. Investigations of their physicochemical properties over time in simulated and real environments and analysis of their interaction with organic matter and common pollutants (e.g. Pd, Hg, Cd) will provide information on their behaviour, enabling prediction of their fate in these environments. Ecotoxicity is a major concern which will be addressed through the analysis of how nanomaterials influence model marine microorganisms, key in understanding how nanomaterials affect the growth and evolution of biological systems.
The outcomes of this research have the opportunity to redefine governmental policy on the risk, use and disposal of nanomaterials by manufacturers and consumers.

Sources of man-made nanoparticles which can end up in the environment.

Methodology

This project aims to investigate the vital, yet poorly-understood impact of commercially-relevant nanomaterials on marine microenvironments. The student will carry out the preparation and extraction (from commercial products) of families of metal and metal oxide nanomaterials of different sizes, shapes and surface functionalities (Figure 2). Their behaviour (colloidal, surface adsorption and degradation) in simulated and real marine environments will be characterised using analytical chemistry techniques, including electron microscopy, infrared and raman spectrocopy, thermogravimetric analysis, x-ray photoelectron spectroscopy and high sensitivity elemental analysis.

The student will also cultivate and collect model and complex microbe colonies, whose interaction with nanomaterials will provide key data on microbial community evolution and proteomics. Cellular variations caused by the interaction with nanomaterials will be assessed by a variety of methods, including growth rate, cellular morphology and high throughput sequencing and proteomics.

The interdisciplinary nature of this project will provide the student with the opportunity to work at the interface between chemistry and life sciences, providing a unique route to illuminate an important area of research with enormous potential impact.

Training and Skills

CENTA students will attend 45 days training throughout their PhD including a 10 day placement. In the first year, students will be trained as a single cohort on environmental science, research methods and core skills. Throughout the PhD, training will progress from core skills sets to master classes specific to the student's projects and themes.

This multidisciplinary PhD project will offer a unique opportunity for the student to learn state-of-the-art techniques in environmental –OMICS (such as high-throughput proteomics and genomics), microbial ecology and biochemistry, preparation of nanomaterials and their extraction from consumer products and analytical chemistry of metal and metal oxide nanomaterials.

The laboratories of supervisors Dr Davies (Department of Chemistry) and Dr Christie-Oleza (School of Life Sciences) are excellently equipped to carry out this cutting-edge project.

Applicants: We are looking for enthusiastic applicants with BSc or MSci in Biology, Biochemistry, Chemistry or related fields. Applicants with 1st class or 2.1 degrees are encouraged to apply; laboratory experience is desirable.

Timeline

Year 1: Preparation of different metal and metal oxide nanomaterials with varying sizes, shapes and surface chemistries. Investigation of nanomaterials’ physicochemical behaviour over time in simulated and real marine solvents. Analytical chemistry techniques will allow determination of their size, crystalline and surface characteristics before, during and after exposure to sea water, as well as identification and quantification of surface adsorption of organic materials and pollutants.

Year 2: Colonisation of model marine microbes and investigation of the effect of incubation with nanoparticles on physiological processes and cellular responses. Identification of biomarkers of stress.

Year 3: Analysis of the ecotoxic effect of nanomaterials on complex marine microcosms (harvested during field work).
The student will also have the opportunity to embark on fieldwork to sample seawater from relevant (well-defined) coastal locations (e.g. Mallorca coast).

Partners and collaboration (including CASE)

This project has a high potential in becoming CASE, building collaborations within industries which explore and use nanomaterials in their products.

Further Details

Potential applicants are invited to contact Gemma-Louise Davies (g-l.davies@warwick.ac.uk) for more details and to express an interest in the project.