title: Determination of furosemide in whole blood using SPE and GC-EI-MS.
abstract: A simple and rapid method was validated to determine furosemide in whole blood. The experimental work was performed so that all validation parameters are considered simultaneously in a one-day assay protocol. A solid-phase extraction procedure using BondElut-LRC Certify columns was used to extract this compound from blood samples, while ketoprofen was used as an internal standard. The extracts were analyzed by gas chromatography-electron ionization-mass spectrometry after on-column derivatization with trimethylanilinium hydroxide (0.2M in methanol). Calibration curves were prepared daily, between 0.10 and 5.00 microg/mL, and the correlation coefficients were above 0.9910. The calculated limits of detection and quantitation were 0.010 and 0.045 microg/mL, respectively. Control samples at low, medium, and high concentrations (0.30, 0.75, and 3.00 microg/mL) of furosemide of an independent source were measured in the same day. Precision and trueness, calculated in terms of relative standard deviation (%), were less than 15% for all concentration levels. The relative recoveries calculated for the three levels of the control samples were 104%, 89%, and 91%, respectively. In general, a sensitive, specific, and reliable procedure has been developed for the determination of furosemide in whole blood samples and was found suitable for the application in postmortem forensic toxicology routine analysis.
authors.affiliation: Instituto Nacional de Medicina Legal, Delegação de Coimbra, Largo da Sé Nova, Portugal. claudiamargalho@iol.pt
authors.forename: Cláudia
authors.initials: C
authors.lastname: Margalho
authors.forename: Douwe
authors.initials: D
authors.lastname: de Boer
authors.forename: Eugenia
authors.initials: E
authors.lastname: Gallardo
authors.forename: Mário
authors.initials: M
authors.lastname: Barroso
authors.forename: Duarte Nuno
authors.initials: DN
authors.lastname: Vieira
mesh_terms: D002849:Chromatography, Gas; D004232:Diuretics / Q000097:blood* / Q000506:poisoning; D000431:Ethanol / Q000097:blood; D005260:Female; D005665:Furosemide / Q000097:blood* / Q000506:poisoning; D006801:Humans; D007202:Indicators and Reagents; D008875:Middle Aged; D000644:Quaternary Ammonium Compounds; D015203:Reproducibility of Results; D021241:Spectrometry, Mass, Electrospray Ionization; D015813:Substance Abuse Detection / Q000379:methods*
chemical_list: D004232:Diuretics; D007202:Indicators and Reagents; D000644:Quaternary Ammonium Compounds; C009571:phenyltrimethylammonium; D000431:Ethanol; D005665:Furosemide