Toxicology of Manufactured Nanoparticles

We are currently involved in a collaborative project with Leicester Royal Infirmary to study the effect of nano-particle pollution on lung cells (alviolar macrophages).

This collaborative project combines expertise in physics and medicine to research possible toxic damage from inhaled nanoparticles. Such particles, in the size range 5-500 nm, are now manufactured and released into the environment on industrial scales. Their small size gives many novel and useful properties and they are used in applications as diverse as face creams, plastics, medical imaging and magnetic recording. However, there is growing concern that the very same properties may also lead to enhanced toxicity if the particles are ingested. Image (right): TEM image of a fractal dust of agglomerated gold nanoparticles (d= 5 to 100 nm).

Alveolar macrophage cells are part of the body's immune system and normally reside deep in the lungs where they form the first line of defence against inhaled particles. We will expose, in vitro, human macrophages cells to an aerosol of metal nanoparticles and measure and toxic damage to their DNA. Precise control over the size, chemical composition and dose of particles with enable us to determine whether there is a correlation between size and toxicity. Image (left): A micron-sized Pb particle made from 50 nm Pb clusters.

EXAFS

Extended fine structure spectroscopy (EXAFS) is a powerful and versatile technique which we use to study the local atomic structure within a vast array of systems.

Our work at the physics/biology interface is done primarily in collaboration with Sheffield Hallam University. We are investigating gold nanoparticles produced by Germanium roots, and also studying the efficiency of some plants, typically seaweed, at removing heavy metals from polluted soils. Image (right): EXAFS data and fit for Cadmium adsorbed on dealginated seaweed.

We are also collaborating with the chemistry department at Leicester to study the structural response of electrochemically modified transition metal oxide films using EXAFS. Finally, on the theoretical side, we use Reverse Monte Carlo simulation methods for the analysis of Surface X-ray diffraction data. Monte Carlo simulation of the configurational entropy of Si(1-x)C(x)