title: Sequential injection extraction based on restricted access material for determination of furosemide in serum.
abstract: Restricted access material (RAM) column containing 25 microm C18 alkyl-diol support was integrated into the sequential injection analysis (SIA) manifold and the SIA-RAM system was tested for direct determination of furosemide in serum. LiChrospher ADS column based on restricted access material is proposed to direct injection of biofluids. The integration of RAM material into SIA enabled creation of a comprehensive on-line sample clean-up technique combined with fluorescence quantitation of analyte. Centrifuged and diluted serum sample was aspirated into the system and loaded onto the column using acetonitrile-water (2:98), pH 2.7. The analyte was retained on the column while proteins contained in the sample were removed to the waste without precipitation and clogging the column. Interfering substances complicating the detection were washed out by acetonitrile-water (15:85), pH 2.7 in the next step. The extracted analyte was eluted by means of acetonitrile-water (25:75), pH 2.3 to the fluorescence detector (emission filter 385 nm). The whole procedure comprising sample pre-treatment, analyte detection and column reconditioning took 20 min. The recoveries of furosemide from serum lay between 101.4 and 103.4% for three concentrations of analyte.
authors.affiliation: Department of Analytical Chemistry, Charles University in Prague, Faculty of Pharmacy in Hradec Králové, Heyrovského 1203, 500 05 Hradec Králové, Czech Republic.
authors.forename: Jitka
authors.initials: J
authors.lastname: Huclová
authors.forename: Dalibor
authors.initials: D
authors.lastname: Satínský
authors.forename: Tiago
authors.initials: T
authors.lastname: Maia
authors.forename: Rolf
authors.initials: R
authors.lastname: Karlícek
authors.forename: Petr
authors.initials: P
authors.lastname: Solich
authors.forename: Alberto Nova
authors.initials: AN
authors.lastname: Araújo
mesh_terms: D000327:Adsorption; D002138:Calibration; D002851:Chromatography, High Pressure Liquid / Q000379:methods*; D004232:Diuretics / Q000097:blood*; D005665:Furosemide / Q000097:blood*; D006863:Hydrogen-Ion Concentration; D012015:Reference Standards; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D013050:Spectrometry, Fluorescence
chemical_list: D004232:Diuretics; D005665:Furosemide