Establishment of a Method for the Determination of Trace Phosphorus in Water by ICP-MS/MS and Its Application in Xin'anjiang Reservoir
An inductively coupled plasma coupled with triple quadrupole mass spectrometric(ICP-MS/MS)method was established for the determination of trace total phosphorus(TP),dissolved phosphorus(DP)and particulate phosphorus(PP)in surface water samples.The instrument parameters and oxygen flow rate for the determination of phosphorus in water by ICP-MS/MS were determined.The detection limit,precision and accuracy of the method for the determination of phosphorus in surface water were studied.The effects of turbidity,chromaticity and the presence of arsenic,chromium and sulfur on the determination of phosphorus by ICP-MS/MS were explored.The results show that trace phosphorus in surface water can be detected by ICP-MS/MS with high purity oxygen,and the detection limit of this method is 0.24 μg/L,the method has good linearity in the range of 1.00~1 000 μg/L,the correlation coefficient is 0.999 5,and the recoveries are between 92%to 103%.This method has fast detection speed and strong resistance to the interference of turbidity,chromaticity,arsenic,chromium and sulfur.The monitoring data of Xin'anjiang Reservoir in four quarters shows that the average concentration of TP in the whole lake of Xin'anjiang Reservoir is 10~20 μg/L,the ratio of DP to TP is 42.4%~50.9%.ICP-MS/MS method therefore can satisfy the determination and speciation analysis of trace phosphorus in surface water.