Automated Flow Injection Coupled with ICP-MS for the Online Determination of Trace Silver in Seawater

This article reports a sensitive analytical procedure for the analysis of silver (Ag) in seawater, using a simple automated flow injection system coupled online with inductively coupled plasma mass spectrometry (ICP MS). Parameters including flow rate and duration, and the effects of the pH and dissolved organic matter (DOM) concentration and salinity were investigated. The standard addition method was used for the quantification. The linear range of the method was up to 1000 ng/kg. For samples with various salinities the relative standard deviations were <3% (n = 5), and the recoveries were 98.88-101.67%. Silver concentrations of SLEW-3 and CASS-4 certified reference materials obtained in this work agreed with results in other studies. The limit of detection was 0.06 ng/kg with a sample volume of 7.5 mL, and the sample throughput was 7 h(-1). This method was successfully used for the determination of Ag in samples from the Jiulong River Estuary.