Determination of Li, Rb, B and Sr in seawater by ICP-MS

Determination of Li, Rb, B and Sr in seawater does not need to use complicated methods used for determination of trace elements in seawater such as chelation-separation and standard addition calibration. It can be performed briefly by diluting seawater by 50 times directly, tuning the sensitivity of Inductively Coupled Plasma Mass Spectrometry(ICP-MS) and adding internal standard Re on line. The examination limit(3σ) for Li, Rb, B and Sr was 0.75, 0.25, 14.0 and 0.10 μg/L respectively. After 10 times continuous determination of seawater samples, the relative standard deviation(RSD) was calculated: the RSD of Li was 1.47%, B was 3.13%, Rb was 2.05% and Sr was 2.01%. The standard was added to assess the recovery of experimentand the recovery rate was from 96.5% to 105%. The results show that this method is simple, fast, and the data is stable, accurate and reliable, which well met the requirement for determination of these elements in seawater. We have measured these four elements in Atlantic bottom water(from the Underwater at 200 meters). The data deviation was less than 2.65%, which was lower than the standard deviation of the method. The seawater in this layer is steady and there is no change.