Speciation analysis of mercury and tin compounds in water and sediments by gas chromatography-mass spectrometry following preconcentration on C60 fullerene

A simple method for the determination of mercury and tin compounds in water and sediments by solid-phase extraction-gas chromatography-mass spectrometry is proposed. The analytes are complexed with sodium diethyldithiocarbamate, retained on a C60 fullerene column and eluted with ethyl acetate containing sodium tetra-n-propylborate as derivatizing reagent. The analytical figures of merit of the proposed method in the selective ion monitoring mode include: limits of detection from 0.8 to 1.5 pg ml−1 (sample volume 50 ml) and precision (as relative standard deviation) from 6.2 to 7.4%. The method is quite selective: the determination of mercury and tin species is subject to no interferences from metal ions such as Zn2+, Fe3+, Sb3+, As3+, Pb2+, Ni2+, Cu2+, Co2+, Mn2+and Cd2+. The accuracy of the method was evaluated from recovery values and the analysis of two standard reference coastal sediments (CRM 462 and CRM 580). The method was also applied to the determination of mercury and tin compounds in water and coastal sediment samples.