title: Sensitive determination of aspirin and its metabolites in plasma by LC-UV using on-line solid-phase extraction with methylcellulose-immobilized anion-exchange restricted access media.
abstract: We describe a sensitive determination of aspirin (ASA) and its three metabolites (salicylic acid [SA], 2,3-dihydroxybenzoic acid [2,3-DHBA], and 2,5-dihydroxybenzoic acid [gentisic acid (GA)]) in rat plasma. Analysis was carried out by on-line solid-phase extraction (SPE) using a methylcellulose-immobilized-strong anion-exchanger (MC-SAX), followed by liquid chromatography (LC) coupled with UV detection. The lower limits of quantitation for ASA and SA were 60 ng/mL in 100 microL of plasma, respectively. This method was validated with respect to intra- and inter-day precision, accuracy, and linearity up to concentrations of 20,000 ng/mL for ASA, SA, 2,3-DHBA and gentisic acid, respectively. The method was successfully applied to an analysis of the pharmacokinetics of ASA and SA in rats.
authors.affiliation: Analytical Research Laboratories, Eisai Co., Ltd., 5-1-3 Tokodai, Tsukuba, Ibaraki 300-2635, Japan. e-yamamoto@hhc.eisai.co.jp
authors.forename: Eiichi
authors.initials: E
authors.lastname: Yamamoto
authors.forename: Susumu
authors.initials: S
authors.lastname: Takakuwa
authors.forename: Takashi
authors.initials: T
authors.lastname: Kato
authors.forename: Naoki
authors.initials: N
authors.lastname: Asakawa
mesh_terms: D000818:Animals; D000837:Anion Exchange Resins; D001241:Aspirin / Q000097:blood* / Q000493:pharmacokinetics; D002852:Chromatography, Ion Exchange / Q000379:methods*; D008297:Male; D008747:Methylcellulose / Q000737:chemistry*; D051381:Rats; D017207:Rats, Sprague-Dawley; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D013056:Spectrophotometry, Ultraviolet / Q000379:methods*
chemical_list: D000837:Anion Exchange Resins; D008747:Methylcellulose; D001241:Aspirin