title: Measurement of nitrite and nitrate levels in biological samples by capillary electrophoresis.
abstract: Nitrite is one of the products of NO-synthase in biological media. It is slowly oxidized in animals to nitrate. We developed a simple and rapid method to determine simultaneously nitrite and nitrate in biological samples. Capillary ion electrophoresis with direct UV detection at 214 nm was used employing a carrier electrolyte consisting of 10 mM sodium sulfate and an electroosmotic flow modifier. The detection limit in ultrafiltrates of plasma, urine and brain tissue extracts was 25 ng/ml for both compounds. Nitrate levels in human plasma and urine were in the microgram/ml range. Nitrite could not be detected. Rat brain tissue extracts contained detectable amounts of nitrite and nitrate.
authors.affiliation: Faculté de médecine Xavier-Bichat, Laboratoire de Biophysique, Paris, France.
authors.forename: A
authors.initials: A
authors.lastname: Meulemans
authors.forename: F
authors.initials: F
authors.lastname: Delsenne
mesh_terms: D000818:Animals; D001923:Brain Chemistry; D004586:Electrophoresis; D006801:Humans; D009566:Nitrates / Q000032:analysis*; D009573:Nitrites / Q000032:analysis*; D051381:Rats; D013056:Spectrophotometry, Ultraviolet; D014462:Ultrafiltration
chemical_list: D009566:Nitrates; D009573:Nitrites