Fluorometric determination of ammonia in sea and estuarine waters by direct segmented flow analysis

摘要: Abstract A direct automated method for routine determination of ammonia in sea and estuarine waters has been developed using segmented flow analysis. The method, based on the reaction with orthophtaldialdehyde (OPA) sulfite, is easy to use, sensitive highly reproducible. combination reagents makes it selective, thus eliminating need gas diffusion cell commonly used remove amino acid interference. Results kinetics, reagent composition light effects pH salinity changes are presented. salt-effect does not exceed 3% 0–35 range. Interference from primary amines −1 ); specific recommendations provided accordingly. Repeatability 0.01 μmol l was achieved marine samples concentrations ranging 0.5 5 . Using on-line dilution, can be performed up 250 salt effect becomes negligible. Comparison present OPA-method indophenol blue yielded fully comparable results.