| A hyphenated technique of liquid chromatography and atomic fluorescence spectrometry was developed for the determination of arsenic species in seawater. The experimental parameters such as mobile phase concentration, pH and flow rate were optimized. Under the optimized experimental conditions, three arsenic species of As (III), As (methyl) and As (V) can be separated and detected in 6 minutes by using Hamilton PRP-X100 analytical column. Under the reaction conditions of carrier flow (5% HCl)and reducer(2% KBH4+0.5%KOH), the injection amount was 100 μL, and the detection limits for trivalent arsenic, methyl arsenic and pentavalent arsenic were 0.31 μg/L, 0.52 μg/L and 0.36 μg/L, respectively. In the range of concentration from 2 μg/L to 80 μg/L, there were good linearity among the three arsenic forms, and the linear coefficients were all better than 0.999. The established method was successfully applied to the determination of arsenic species in seawater samples. The measured concentrations of As (III) and As (methyl) were low relatively, and the concentration of As (V) was slightly higher, which indicated that As (V) was the main form of arsenic in seawater. When the adding standard matter amount were 5 μg/L and 10 μg/L, the recoveries were satisfactory (73%~104%). This method is relatively simple, sensitive, cheap and low operation cost. It is suitable for the determination of arsenic species in seawater. |
