Determination of antimony in seawater by graphite furnace atomic absorption spectrometry with Zeeman-effect background correction and using ammonium nitrate as the matrix modifier

An ETAAS method was developed for the determination of antimony (Sb) in seawater using ammonium nitrate as the matrix modifier plus Zeeman-effect background correction. The concentration selected for the modifier was 35.2 μg/mL, and the temperature program selected for the graphite furnace for a spiked sample was 1200°C and 1900°C for mineralization and atomization, respectively. The use of the standard additions method was mandatory due to the matrix effects observed. The LOD and LOQ achieved were 2.7 and 9.0 pg/L, respectively; 9.6 pg was the mean characteristic mass obtained within the linear range of concentrations (0-20 μg/L Sb). The method was applied to spiked coastal seawater samples from the Mediterranean Sea.