Sequential injection (SIA) present attractive characteristics for analyses in large scale. In SIA the analytical determination can be perfomed automatically reducing the number of steps usually involved in a chemical analysis. In order to laboratory dedicated to routine analyze, the determination of volatile nitrogen in silge and soil samples has been performed. The nitrogen content was deermined afther NH, on-line separation in alkaline conditions by using a gaseus diffision or a pervaporatioin unit for liquid separatioin. An ammonium tubular selective alectrode detector was used for determinations
