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Using sequential injection analysis to improve system and data reliability of online methods: determination of ammonium and phosphate in coastal waters.

Frank C, Schroeder F - J Autom Methods Manag Chem (2007)

Bottom Line: These measures are advantageous during method development and validation and can be used to verify the system performance on a regular base to reduce the amount of erroneous results.No changes in the flow system are necessary and the sample throughput is only slightly reduced.Results from a campaign in summer 2005 are shown.

View Article: PubMed Central - PubMed

Affiliation: GKSS Research Centre, Institute for Coastal Research, Max-Planck-Strasse, 21502 Geesthacht, Germany.

ABSTRACT
This article summarises the advantages of the sequential injection analysis (SIA) for the online determination of nutrients in coastal waters. It concentrates on techniques to improve the reliability of the gained data by continuously monitoring one or more standards and on the advantages of online standard additions and offline determination of manually collected samples with the online SIA system. These measures are advantageous during method development and validation and can be used to verify the system performance on a regular base to reduce the amount of erroneous results. No changes in the flow system are necessary and the sample throughput is only slightly reduced. These techniques have been applied to a SIA system which is able to simultaneously determine ammonium and phosphate at a rate of more than 100 samples per hour each and detection limits (3sigma) of 0.06 muM and 0.05 muM. Results from a campaign in summer 2005 are shown.

No MeSH data available.


Scheme of the SIA used for the fast determination ofammonium and phosphate. RA: reagent for the determination ofammonium, RP1: reagent one for the phosphate determination, RP2:reagent two for the phosphate determination, rl 1–3: reactionloops for the determination of ammonium, rl 4: reactionloop for the determination of phosphate.
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Figure 1: Scheme of the SIA used for the fast determination ofammonium and phosphate. RA: reagent for the determination ofammonium, RP1: reagent one for the phosphate determination, RP2:reagent two for the phosphate determination, rl 1–3: reactionloops for the determination of ammonium, rl 4: reactionloop for the determination of phosphate.

Mentions: Two different fluorescence detectors are used in this setup(see Figure 1). A Hitachi F1000 fluorescence spectrometer(ex. 365 nm, emm. 425 nm) is used for the determination ofammonium. It is connected to an HP 34401A digital multimeter whichis used as an analog-to-digital converter. The Hitachi fluorescencespectrometer is connected to the valve via three identicalreaction loops (60 cm; 0.8 mm i.d.) which are heated usinghome-made pipe system connected to a Haake DC 50 heating bath.Phosphate is determined via a fluorescence detector (ex.470 nm, emm. 550 nm) provided by IPHT Jena (Germany). Itis connected via a reaction loop (60 cm; 0.8 mm i.d.) tothe valve and uses a digital multimeter with RS232 connection(keithley model 2000) as an analog-to-digital converter. Allcomponents (the syringe pump, the valve, the multimeters, and theheating bath) are connected via RS232 to a personal computer whichcontrols the whole setup by scripts written in the pythonprogramming language.


Using sequential injection analysis to improve system and data reliability of online methods: determination of ammonium and phosphate in coastal waters.

Frank C, Schroeder F - J Autom Methods Manag Chem (2007)

Scheme of the SIA used for the fast determination ofammonium and phosphate. RA: reagent for the determination ofammonium, RP1: reagent one for the phosphate determination, RP2:reagent two for the phosphate determination, rl 1–3: reactionloops for the determination of ammonium, rl 4: reactionloop for the determination of phosphate.
© Copyright Policy - open-access
Related In: Results  -  Collection

Show All Figures
getmorefigures.php?uid=PMC1828606&req=5

Figure 1: Scheme of the SIA used for the fast determination ofammonium and phosphate. RA: reagent for the determination ofammonium, RP1: reagent one for the phosphate determination, RP2:reagent two for the phosphate determination, rl 1–3: reactionloops for the determination of ammonium, rl 4: reactionloop for the determination of phosphate.
Mentions: Two different fluorescence detectors are used in this setup(see Figure 1). A Hitachi F1000 fluorescence spectrometer(ex. 365 nm, emm. 425 nm) is used for the determination ofammonium. It is connected to an HP 34401A digital multimeter whichis used as an analog-to-digital converter. The Hitachi fluorescencespectrometer is connected to the valve via three identicalreaction loops (60 cm; 0.8 mm i.d.) which are heated usinghome-made pipe system connected to a Haake DC 50 heating bath.Phosphate is determined via a fluorescence detector (ex.470 nm, emm. 550 nm) provided by IPHT Jena (Germany). Itis connected via a reaction loop (60 cm; 0.8 mm i.d.) tothe valve and uses a digital multimeter with RS232 connection(keithley model 2000) as an analog-to-digital converter. Allcomponents (the syringe pump, the valve, the multimeters, and theheating bath) are connected via RS232 to a personal computer whichcontrols the whole setup by scripts written in the pythonprogramming language.

Bottom Line: These measures are advantageous during method development and validation and can be used to verify the system performance on a regular base to reduce the amount of erroneous results.No changes in the flow system are necessary and the sample throughput is only slightly reduced.Results from a campaign in summer 2005 are shown.

View Article: PubMed Central - PubMed

Affiliation: GKSS Research Centre, Institute for Coastal Research, Max-Planck-Strasse, 21502 Geesthacht, Germany.

ABSTRACT
This article summarises the advantages of the sequential injection analysis (SIA) for the online determination of nutrients in coastal waters. It concentrates on techniques to improve the reliability of the gained data by continuously monitoring one or more standards and on the advantages of online standard additions and offline determination of manually collected samples with the online SIA system. These measures are advantageous during method development and validation and can be used to verify the system performance on a regular base to reduce the amount of erroneous results. No changes in the flow system are necessary and the sample throughput is only slightly reduced. These techniques have been applied to a SIA system which is able to simultaneously determine ammonium and phosphate at a rate of more than 100 samples per hour each and detection limits (3sigma) of 0.06 muM and 0.05 muM. Results from a campaign in summer 2005 are shown.

No MeSH data available.