Photosensitization properties of carbon-60 and fullerol aqueous suspensions

This work provides a framework by which to judge the photochemical properties of water suspended fullerene and its derivatives. Assessment of photosensitization properties is essential to understanding the potential of nanoparticles such as fullerene to impact the environment. Measurements of the presence and the rate of reactive oxygen species generation were carried out via three unique trapping methods: electron paramagnetic resonance; dissolved oxygen trapping by furfuryl alcohol; and reduction of nitro blue tetrazolium. A quantitative comparison photosensitization finds unfunctionalized clustered fullerene suspensions to have no photoactivity whereas functionalized and aggregated fullerenes exhibit type I and type II photosensitization. These findings build upon results from previous studies in polar and non-polar solvents, and also serve to provide a deeper understanding of past nanoparticle toxicity studies which provide unclear explanations of mechanisms for cell death. This framework will inform future precautionary and engineering design environmental work with fullerene