title: Determination of oxytetracycline in tomatoes by HPLC using fluorescence detection.
abstract: An analytical method for the determination of oxytetracycline (OTC) in tomatoes was developed and validated. Liquid-liquid extraction (LLE) and a solid-phase extraction (SPE) were used for sample preparation. Reversed-phase high performance liquid chromatography (RP-HPLC) using a C18 column and a mobile phase containing MeOH: calcium chloride, disodium ethylenediaminetetraacetate (EDTA) and sodium acetate, pH 7.3 (30:70, v/v), with fluorescence detection at 390nm excitation and 512nm emission, was used for separation and quantitation of OTC. The method was validated through the following performance criteria: linearity and linear range, sensitivity, selectivity, intra-day and inter-day precision, detection and quantitation limits and accuracy. Limit of quantitation show that the method developed is suitable for the determination of OTC at a level below the maximum residue limits established by the Brazilian legislations (250μgkg(-1)). Of 40 samples analyzed, none contained OTC above the limit of quantitation.
authors.affiliation: Department of Food Science, State University of Campinas, P.O. Box 6121, 13084-971 Campinas, SP, Brazil.
authors.forename: Patrícia Penido
authors.initials: PP
authors.lastname: Maia
authors.affiliation: Institute of Chemistry, Department of Analytical Chemistry, State University of Campinas, P.O. Box 6154, 13084-971 Campinas, SP, Brazil.
authors.forename: Susanne
authors.initials: S
authors.lastname: Rath
authors.affiliation: Department of Food Science, State University of Campinas, P.O. Box 6121, 13084-971 Campinas, SP, Brazil. Electronic address: reyesfgr@fea.unicamp.br.
authors.forename: Felix Guillermo Reyes
authors.initials: FG
authors.lastname: Reyes
keywords: Antibiotics; High performance liquid chromatography; Method validation; Oxytetracycline; Tomatoes