Quantifying summed fullerene nC60 and related transformation products in water using LC LTQ Orbitrap MS and application to environmental samples

The application of engineered nanomaterials increases strongly. Development of analytical techniques and their application to environmental samples is essential for human and environmental risk assessment of the nanoparticles. The objective 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. nC60 can be transformed by oxidation, reduction and photochemical reaction. Therefore, the formation of some transformation products of nC60 was studied as well. Finally, the developed analytical method was applied to surface water samples from several locations in the Netherlands. The developed method enabled to detect and quantify aqueous concentrations of the summed nC60 and its transformation products as low as 5 ng/L. It was observed that nC60 transformation products exceed quantities of the parent C60. Despite the high sensitivity of the developed method, no nC60 or transformation products were detected in an array of Dutch surface waters. This might be due to low emissions, losses in the aqueous phase by sedimentation, sorption or further transformation processes.

Research highlights
► Developing analytical techniques for nanoparticles is critical for proper risk assessment.
► We used accurate LC LTQ mass spectrometry to quantify nC60 and transformation products in water.
► The method enabled to quantify summed nC60 and transformation products as low as 5 ng/L.
► nC60 transformation products exceed parent C60.
► No nC60 or transformation products were detected in various Dutch surface waters.