Determination of ammonium in aqueous samples using new headspace dynamic in-syringe liquid-phase microextraction with in situ derivitazation coupled with liquid chromatography–fluorescence detection

A novel all-solid-state ammonium electrode with polyaniline and copolymer of aniline/2,5-dimethoxyaniline as transducers

“…Traditional methods for measuring ammonia content were based on Nessler's reagent colorimetry [3], indophenol [4], Ophthaldialdehyde (OPA) and N-acetyl-cysteine (NAC) reagent [5], and titration [6]. Electrochemical methods have attracted great interests in recent years because of its high sensitivity, fast analysis, low detection limit, few reagent requirements, and little cost [7].…”

Deterniillation of Ammonium in Aqueous Samples by Gas Phase Light Scattering Using Hydrogen Chloride Gas as a Derivatizing Reagent Followed by Nondispersive Atomic Fluorescence Spectrometry

“…1,2 Many analytical methods have been reported for the determination of ammonium in different samples. Common methods include spectrophotometry, [3][4][5] fluorescence, 6,7 electrochemistry, 8,9 and ion chromatography (IC). 10 In general, these methods are carried out in the liquid phase.…”

“…For highly selective and fast determination of ammonium in complex matrices, the above detection methods combining flow techniques (FA) and gas diffusion (GD) as a separation technique have been developed. [5][6][7]25 However, the analysis is time consuming, and requires special apparatus. In recent years, solid phase microextraction (SPME) and headspace (HS) have become known as powerful tools for separation and enrichment of ammonia from aqueous samples prior to analysis of ammonium.…”

“…The disadvantage of both procedures is the need for a series of time steps. 4,7 In addition, ammonium can also be determined by gas phase molecular absorption spectrometry (GPMAS) by evolution and measurement of ammonia using an atomic absorption spectrophotometer. 11,12 However, the method is limited by its low sensitivity and expensive spectrophotometric equipment.…”

Monitoring of nitrite, nitrate, chloride and sulfate in environmental samples using electrophoresis microchips coupled with contactless conductivity detection

“…Besides nitrite and nitrate, the monitoring of ammonium concentration levels is quite relevant, once it is considered the most severe pollutant causing eutrophication of aquatic ecosystems. The determination of ammonium has been performed using often photometric, fluorescence, and chemiluminescence and electrochemical detectors coupled with IC, flow injection analysis and capillary electrophoresis (CE) techniques [13][14][15]. However, most of the mentioned analytical techniques require derivatization reactions, which are considered laborious and, consequently, time-consuming.…”