Quantifying fullerene C60 including transformation products in water with LC LTQ Orbitrap MS and application to environmental samples

Development of analytical techniques and application to environmental samples is essential for human
and environmental risk assessment of the growing use of engineered nanoparticles. The purpose of this
study was to develop a sensitive analytical method to quantify nC60 in water, using accurate mass
screening liquid chromatography–hybrid linear ion trap Orbitrap mass spectrometry. The
transformation of parent (n)C60 by oxidation, reduction and photochemical reaction is well-known, but
the exact nature of the transformation products is not well studied A second aim was therefore to study
and identify transformation products of C60. Finally, the method was applied to surface water samples
from several locations in the Netherlands. The detection limit as found in the present study is
considerably more sensitive than existing analytical methods for nC60 in water. It is possible to detect
nC60 and transformation products in water at concentrations as low as 5 ng/L. C60 transformation
products are observed, and can exceed parent C60. The accurate mass allows identifying these
transformation products. No nC60 or transformation products are detected in any of the surface waters
monitored. This might be due to low emissions, and/or to high loss factors by sedimentation and
removal due to further transformation processes.