Automatic On-Line Purge-and-Trap Sequential Injection Analysis for Trace Ammonium Determination in Untreated Estuarine and Seawater Samples.

摘要: An innovative automatic purge-and-trap (P&T) system coupled with fluorimetric sequential injection (SI), for the on-line separation and preconcentration of volatile compounds, is presented. The truth concept demonstrated ammonium determination in environmental water samples complex matrices without any pretreatment. P&T flow comprises a thermostated purge-vessel where converted into gaseous ammonia trap-vessel collection. This configuration results matrix removal as well analyte preconcentration, avoiding membrane-associated problems. All main parameters affecting efficiency were studied optimized. proposed method characterized by working range 2.7-150.0 μg L-1 NH4+, detection quantification limit 0.80 2.66 L-1, respectively, 10-mL sample consumption. accuracy was assessed recovery assays seawater, estuarine, lake analysis standard reference material.