title: HPLC analysis of in vivo intestinal absorption and oxidative metabolism of salicylic acid in the rat.
abstract: In vivo absorption and oxidative metabolism of salicylic acid in rat small intestine was studied by luminal perfusion experiment. Perfusion through the lumen of proximal jejunum with isotonic medium containing 250 μm sodium salicylate was carried out. Absorption of salicylate was measured by a validated HPLC-DAD method which was evaluated for a number of validation characteristics (specificity, repeatability and intermediate precision, limit of detection, limit of quantification, linearity and accuracy). The method was linear over the concentration range 0.5-50 μg/mL. After liquid-liquid extraction of the perfusion samples oxidative biotransformation of salicylate was also investigated by HPLC-MS. The method was linear over the concentration range 0.25-5.0 μg/mL. Two hydroxylated metabolites of salicylic acid (2,5-dihydroxybenzoic acid and 2,3-dihydroxybenzoic acid) were detected and identified. The mean recovery of extraction was 72.4% for 2,3-DHB, 72.5% for 2,5-DHB and 50.1% for salicylic acid, respectively. The methods were successfully applied to investigate jejunal absorption and oxidative metabolism of sodium salicylate in experimental animals. The methods provide analytical background for further metabolic studies of salycilates under modified physiological conditions.
authors.affiliation: Institute of Pharmaceutical Chemistry, University of Pécs, H-7624, Pécs, Rókus str. 2, Hungary.
authors.forename: Mónika
authors.initials: M
authors.lastname: Kuzma
authors.affiliation: Institute of Pharmaceutical Chemistry, University of Pécs, H-7624, Pécs, Rókus str. 2, Hungary.
authors.forename: Eszter
authors.initials: E
authors.lastname: Nyúl
authors.affiliation: Department of Forensic Medicine, University of Pécs, H-7624, Pécs, Szigeti str. 12, Hungary.
authors.forename: Mátyás
authors.initials: M
authors.lastname: Mayer
authors.affiliation: Department of Pharmacology and Pharmacotherapy, University of Pécs, H-7624, Pécs, Szigeti str. 12, Hungary.
authors.forename: Emil
authors.initials: E
authors.lastname: Fischer
authors.affiliation: Institute of Pharmaceutical Chemistry, University of Pécs, H-7624, Pécs, Rókus str. 2, Hungary.
authors.forename: Pál
authors.initials: P
authors.lastname: Perjési
mesh_terms: D000818:Animals; D002851:Chromatography, High Pressure Liquid / Q000379:methods*; D007408:Intestinal Absorption; D007583:Jejunum / Q000378:metabolism; D057230:Limit of Detection; D059625:Liquid-Liquid Extraction; D008297:Male; D013058:Mass Spectrometry / Q000379:methods; D010084:Oxidation-Reduction; D051381:Rats; D017208:Rats, Wistar; D012015:Reference Standards; D015203:Reproducibility of Results; D020156:Salicylic Acid / Q000378:metabolism*
chemical_list: D020156:Salicylic Acid
keywords: HPLC-MS; intestinal metabolism; oxidative metabolism; salicylic acid