Quantitative determination of fullerene (C60) in soils by high performance liquid chromatography and accelerated solvent extraction technique

Abstract

Environmental context.Due to the increasing adoption of nanotechnology, synthetic nanoparticles such as fullerenes (nC60), are likely to emerge as contaminants in aquatic and terrestrial environments. Currently, our understanding of the fate and effects of C60 in the terrestrial environment is poor and is primarily hampered by the lack of reliable quantitative analytical methods. In this paper, we describe a method for effective extraction and sensitive detection of C60 residues in soils which will facilitate environmental fate studies on nC60. Abstract.Fullerenes (e.g. C60) are emerging as environmental contaminants due to their wide range of applications, such as in optics, electronics, cosmetics and biomedicine. Residue analysis is a crucial step in understanding the fate and effects of C60 in the terrestrial environments. However, there is a lack of reliable quantitative analytical methods for extraction and analysis of C60 in soils or sediments. We developed a method for determination of C60 in soils using accelerated solvent extraction (ASE) followed by HPLC-UV detection. Separation of C60 from soil matrix interferences was achieved by gradient elution using methanol–toluene mobile phase. Mean recoveries obtained from extraction efficiency tests using six contrasting soils spiked (wet and dry tests with freeze drying of wet and aged soils before ASE) at varying concentrations of C60 ranged from 84 to 107%. The current method provides adequate sensitivity (limit of quantitation = 20 μg kg–1), and can be used for quantitative determination of C60 in soils and sediments (especially for environmental fate studies) without needing expensive HPLC-mass spectrometry.