title: Determination of antipyrine in saliva using the dispersive liquid-liquid microextraction based on a stepwise injection system.
abstract: A fully automated stepwise injection spectrophotometric method for determination of antipyrine in saliva (agent for non-invasive assessment of the activity of the drug metabolizing system in hepatocytes) has been developed. The method is based on the antipyrine derivatization by nitrite-ion dispersive liquid-liquid microextraction (DLLME) of formed 4-nitrosoantipyrine with subsequent UV-vis spectrophotometric detection. Under optimal experimental conditions (0.5 М sulfuric acid, 6×10(-3) М sodium nitrite, time 6 min) the absorbance of the colored extract at the 345 nm obeys Beer׳s law in the range of 3-200 μM of antipyrine in saliva. The LOD, calculated from a blank test, based on 3σ, found to be 1 μM. The relative standard deviation for the determination of 50 μM antipyrine was 4.5% (n=10). The proposed method was successfully applied to the determination of antipyrine in saliva and the analytical results agreed fairly well with the results obtained by reference HPLC method.
authors.affiliation: Department of Analytical Chemistry, Faculty of Chemistry, Saint-Petersburg State University, Saint-Petersburg, pr. Universitetskij 26, 198504 Saint-Petersburg, Russia.
authors.forename: Andrey
authors.initials: A
authors.lastname: Bulatov
authors.affiliation: Department of Analytical Chemistry, Faculty of Chemistry, Saint-Petersburg State University, Saint-Petersburg, pr. Universitetskij 26, 198504 Saint-Petersburg, Russia. Electronic address: ksmed90@gmail.com.
authors.forename: Kseniia
authors.initials: K
authors.lastname: Medinskaia
authors.affiliation: Department of Analytical Chemistry, Faculty of Chemistry, Saint-Petersburg State University, Saint-Petersburg, pr. Universitetskij 26, 198504 Saint-Petersburg, Russia.
authors.forename: Darina
authors.initials: D
authors.lastname: Aseeva
authors.affiliation: Department of Analytical Chemistry, Certification and Quality Management, Kazan National Research Technological University, Kazan 420015, ul. K.Marksa 68, Russia.
authors.forename: Sergei
authors.initials: S
authors.lastname: Garmonov
authors.affiliation: Department of Analytical Chemistry, Faculty of Chemistry, Saint-Petersburg State University, Saint-Petersburg, pr. Universitetskij 26, 198504 Saint-Petersburg, Russia.
authors.forename: Leonid
authors.initials: L
authors.lastname: Moskvin
mesh_terms: D000894:Anti-Inflammatory Agents, Non-Steroidal / Q000032:analysis*; D000983:Antipyrine / Q000032:analysis*; D002851:Chromatography, High Pressure Liquid; D004867:Equipment Design; D006801:Humans; D057230:Limit of Detection; D059627:Liquid Phase Microextraction / Q000295:instrumentation*; D012463:Saliva / Q000737:chemistry*; D013056:Spectrophotometry, Ultraviolet
chemical_list: D000894:Anti-Inflammatory Agents, Non-Steroidal; D000983:Antipyrine
keywords: Antipyrine; Dispersive liquid–liquid microextraction; Saliva; Stepwise injection analysis