caa a22 4500 469129549 CHVBK 20180323133200.0 cr unu---uuuuu 170328e19920601xx s 000 0 eng 10.1007/BF00324985 doi (NATIONALLICENCE)springer-10.1007/BF00324985 Determination of nitrite as pentafluorobenzyl derivative by RP-HPLC and UV detection with and without ion-pair extraction [Elektronische Daten] [Dimitrios Tsikas, Jürgen Frölich] Summary: A reversed-phase high-performance liquid chromatographic (RP-HPLC) method with UV detection (270 nm) for the determination of nitrite as its pentafluorobenzyl derivative with and without ion-pair extraction is described. Ion-pair extraction of nitrite from aqueous solutions was performed by using a 1 mol/l solution of the liquid ion exchanger methyltrioctylammonium chloride in toluene. The residue of the ion-pair extraction or an aliquot of an aqueous nitrite solution or of a biological fluid (100 μl) were treated with 400 μl of acetone and 10 μl of pentafluorobenzyl bromide. Nitrite was converted into its pentafluorobenzyl derivative by heating at 50°C for 90 min. After evaporation of acetone the aqueous phases were diluted with 100 to 400 μl of methanol, and up to 100 μl were injected into the RP-HPLC system. The method allows accurate analysis of nitrite in the presence of nitrate directly in aqueous solutions and biological fluids in concentrations down to 2.0 mg/l. The method is also applicable to the determination of nitrate following its reduction to nitrite by cadmium. Springer-Verlag, 1992 Tsikas Dimitrios Department of Clinical Pharmacology, Hannover Medical School, Konstanty-Gutschow-Strasse 8, W-3000, Hannover, Germany aut Frölich Jürgen Department of Clinical Pharmacology, Hannover Medical School, Konstanty-Gutschow-Strasse 8, W-3000, Hannover, Germany aut Fresenius' Journal of Analytical Chemistry Springer-Verlag 344/6(1992-06-01), 256-260 0937-0633 344:6<256 1992 344 216 https://doi.org/10.1007/BF00324985 text/html Onlinezugriff via DOI 1 research-article jats NATIONALLICENCE 856 40 https://doi.org/10.1007/BF00324985 text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Tsikas Dimitrios Department of Clinical Pharmacology, Hannover Medical School, Konstanty-Gutschow-Strasse 8, W-3000, Hannover, Germany aut NATIONALLICENCE 700 1- Frölich Jürgen Department of Clinical Pharmacology, Hannover Medical School, Konstanty-Gutschow-Strasse 8, W-3000, Hannover, Germany aut NATIONALLICENCE 773 0- Fresenius' Journal of Analytical Chemistry Springer-Verlag 344/6(1992-06-01), 256-260 0937-0633 344:6<256 1992 344 216 Metadata rights reserved Springer special CC-BY-NC licence nationallicence BK010053 XK010053 XK010000 NATIONALLICENCE NATIONALLICENCE NL-springer