title: Analysis of Valproic Acid, Salicylic Acid and Ibuprofen in Whole Blood by GC-MS.
abstract: The Georgia Bureau of Investigation utilized a silylation method of analysis for low molecular weight carboxylic acids in the past. Due to the negative impact such derivatizations can have on gas chromatography-mass spectrometry (GC-MS) systems an alternative means of analysis was investigated. The described method is a whole blood solid phase extraction of valproic acid, salicylic acid and ibuprofen utilizing butylation for sensitivity and improved chromatography by GC-MS. The method produced a limit of detection and limit of quantitation at 1 mg/L for valproic acid, 2 mg/L for salicylic acid and 0.25 mg/L for ibuprofen. The variability based upon the middle of the calibration curve estimated to be 7% for valproic acid, 8% for salicylic acid and 11% for ibuprofen established upon a 95% confidence interval, with the highest percent coefficient of variation being 5.3% for ibuprofen.
authors: GBI Division of Forensic Sciences, P.O. Box 370808, Decatur, GA, USA jon.stephenson@gbi.ga.gov.
authors: Jon B
authors: JB
authors: Stephenson
authors: GBI Division of Forensic Sciences, P.O. Box 370808, Decatur, GA, USA.
authors: Melanie L
authors: ML
authors: Flater
authors: GBI Division of Forensic Sciences, P.O. Box 370808, Decatur, GA, USA.
authors: Lisa T
authors: LT
authors: Bain
mesh_terms: D002138:Calibration; D008401:Gas Chromatography-Mass Spectrometry; D005845:Georgia; D006801:Humans; D007052:Ibuprofen / Q000097:blood*; D057230:Limit of Detection; D008970:Molecular Weight; D015203:Reproducibility of Results; D020156:Salicylic Acid / Q000097:blood*; D052616:Solid Phase Extraction; D053719:Tandem Mass Spectrometry; D014635:Valproic Acid / Q000097:blood*
chemical_list: D014635:Valproic Acid; D020156:Salicylic Acid; D007052:Ibuprofen