A submersible flow-injection analyser for the in-situ determination of nitrite and nitrate in coastal waters

Development and initial deployments of an autonomous in situ instrument for long‐term monitoring of copper (II) in the marine environment

“…In situ chemical analyzers have been developed and successfully deployed for periods of up to a year for macronutrients such as nitrate and nitrite (Chapin et al 2004;Daniel et al 1995) and trace metals such as iron, zinc, and copper (Fe: Chapin et al 2002;Laës et al 2005; Zn: Chapin and Wanty 2005;Cu: Callahan et al 2004). These analyzers are essentially miniaturized, submersible versions of classic wet chemical bench-top methods.…”

Flow injection analysis as a tool for enhancing oceanographic nutrient measurements—A review

“…in tethered buoys, as described by Répécaud et al [240]. There has been limited, but continuing development of FIA in submersible systems and on remotely operated vehicles (ROVs) [128][129][130][131]180,[241][242][243][244][245][246], and there is great potential in this area, given the developments in microfluidic devices during the last decade. The microfluidic flow device described by Beaton et al for the determination of nitrate [247] is an example of the new generation of flow analysis devices under development.…”

“…diazotization with sulfanilamide followed by coupling with N-(1-naphthyl)-ethylenediamine dihydrochloride (NED) to form a pink azo dye [125]. Johnson and Petty [126] first described the use of FIA for nitrate measurement in marine waters using Cd reduction and the Griess reaction for nitrite detection, and their work has been adapted by many for surface [127] and submersible systems [27,[128][129][130][131].…”

Underway monitoring of nanomolar nitrate plus nitrite and phosphate in oligotrophic seawater

“…The feasibility of flow-injection techniques with spectroscopic detection for remote deployment to measure multiple variables with high resolution has been described recently (Manrahan et al 2002). Further improvement and application of these systems in field observations will greatly advance our Although several methods for nitrate and nitrite determinations in seawater have been reported, including spectrophotometry, chemilumenesence, electrophoresis, florescence spectroscopy, high pressure liquid chromatography (HPLC), and ion chromatography (Garside 1982;Kieber and Seaton 1995;Daniel et al 1995;Hansen and Koroleff 1999;Okemgbo et al 1999;Masserini and Fanning 2000;Manrahan et al 2002;Thouron et al 2003;Ito et al 2005), the colorimetric method with cadmium reduction remains the most popular technique for nitrate determinations in natural waters (Moorcroft et al 2001). To increase sensitivity, long-path flow cells have been successfully incorporated into conventional spectrophotometric methods for nitrate and nitrite measurements at nanomolar level (Yao et al 1998;Zhang 2000).…”