title: Development of a new quantitative method for detection of endotoxin by fluorescence labeling of 3-hydroxy fatty acid.
abstract: New quantitative method for the detection of minute amounts of endotoxin has been developed using 3-hydroxytetradecanoic acid as a chemical marker. After converting 3-hydroxytetradecanoic acid to methyl ester, it was coupled with a fluorescent probe, anthracene-9-carboxyl chloride, obtained by chlorization of 9-anthroic acid with oxalyl chloride. The resulting ester was isolated by HPLC on silica column. The purified product, methyl-3-0-(9-carboxy-anthracenyl) tetradecanoate (M/Z 462), was highly responsive to a fluorescence spectrophotometer, showing maximum emission with excitation wavelength at 257 nm and emission wavelength at 458 nm in dichloromethane, the limit of detection being as little as 10 f mol. Using this method it is currently possible to detect Salmonella abortus equi endotoxin in aqueous solution at a level of 100 pg.
authors.affiliation: National Institute of Hygienic Sciences, Tokyo, Japan.
authors.forename: K
authors.initials: K
authors.lastname: Tanamoto
mesh_terms: D000873:Anthracenes / Q000138:chemical synthesis; D002849:Chromatography, Gas; D002851:Chromatography, High Pressure Liquid; D004731:Endotoxins / Q000032:analysis*; D005227:Fatty Acids / Q000032:analysis*; D005453:Fluorescence; D008050:Lipid A / Q000032:analysis; D013058:Mass Spectrometry; D009227:Myristic Acids / Q000032:analysis; D011135:Polysaccharides, Bacterial / Q000032:analysis*; D012475:Salmonella / Q000032:analysis / Q000276:immunology*
chemical_list: D000873:Anthracenes; D004731:Endotoxins; D005227:Fatty Acids; D008050:Lipid A; D009227:Myristic Acids; D011135:Polysaccharides, Bacterial; C009893:beta-hydroxymyristic acid; C010030:9-anthroic acid