Determination of phosphorus and sulfur contents in tea by ICP-AES

Phosphorus and sulfur contents in tea samples were simultaneously determined by ICP-AES,and the results obtained from different instrument operating parameters were compared.The authors tried to improve the instrument sensitivity and stability by extending the time of argon gassing and plasma stabilization.Furthermore,they also carried out an methodological study on the testing method with specific operating parameters.RSD of phosphorus and sulfur contents were 1.0% and 2.6%,recovery rates were 94.2%-101.0% and 91.9%-95.6%,and the detection limits were 0.02 μg·g-1 and 0.03 μg·g-1 respectively,which indicated that this method was accurate to meet the requirements for determining phosphorus and sulfur in tea.