Development of analytical methods for ammonium determination in seawater over the last two decades

Ammonium plays an important role in the nitrogen cycle in marine environments. There is no universal method for ammonium analysis that can be applied to all types of seawater and meet the requirements of different applications. Therefore, selecting the most appropriate method is of crucial importance. The aim of this review is to explore the diverse range of methods available for the detection and analysis of ammonium in seawater, to provide a basis for selection of the most suitable method. The developments of typically used methodologies for the analysis of seawater are summarized, including ion-selective electrode, spectrophotometric, fluorometric and matrix separation methods. The main parameters assessed in research published in the last two decades (1999-2019) are also reviewed. To make this review specific to seawater analysis, only methods dealing with actual coastal, estuarine and seawater analysis or having specific salinity effect evaluations, were selected. (C) 2019 Elsevier B.V. All rights reserved.