Highlights

Characterisation of TiO₂ Nanoparticles for Toxicological Investigations

Scientific Achievement

Over the duration of work conducted at the EMC facility at ANL, successful characterization of a suite of TiO₂ nanoparticles was achieved.  Transmission electron microscopy (TEM) techniques were used to observe the presence of different shaped TiO₂ nanoparticles, such as; nanotubes, nanospheres and nanorods.  TEM techniques were also used to assess the level of nanoparticle dispersion attainable after differing surface functionalisation treatments.  Furthermore, TEM was used to attain quantitative estimates of the size distribution of a series of TiO₂ nanorods that were synthesized with differing spatial dimensions.

Energy dispersive X-ray analysis was also used to confirm the successful functionalisation of the TiO₂ nanoparticles with radioisotope encapsulating cage ligands that will be used for future investigations.

Significance

This research has focused on the synthesis and characterization of industrially relevant metal oxide nanoparticles (TiO₂) or various morphologies.  This will facilitate the development of models to correlate nanoparticle composition, size and shape to their biological interaction and potential toxicity.  This type of information is urgently needed for regulatory bodies, as such nanoparticulate entities are already beginning to infiltrate into everyday consumer products and cosmetics.

The TiO₂ nanoparticles which were characterized with EMC instrumentation were also used to conduct surface enhanced Raman spectroscopy (SERS) investigations with various enediol ligans (i.e. neurotransmitter molecules; dopamine and salicylic acid).  This work has been submitted in a brief manuscript to the Journal of American Chemical Society (September 2008).

The collaboration is ongoing with Tijana Rajh accepting an invitation to speak at a conference in Australia and visiting the research labs of the collaborating researchers.  Future directions of the research work will include synthesis of further TiO₂ nanoparticles of varying shape and size at the University of Queensland in Australia.  This will allow us to follow the biological interactions as well as nanoparticle persistence and accumulation through fluorescent and radiolabelling techniques which have been developed.  Additionally, further investigations into SERS phenomena observed in the presence of TiO₂ nanoparticles are planned.

Performers