title: Determination of tamoxifen and its main metabolites in plasma samples from breast cancer patients by micellar liquid chromatography.
abstract: A method was developed for the analysis of tamoxifen and its main derivatives (4-hydroxytamoxifen, N-desmethyl-tamoxifen, tamoxifen-N-oxide and endoxifen) in human plasma, using micellar liquid chromatography coupled with fluorescence detection. Analytes were off-line derivatized by sample UV-irradiation for 20 min to form the photocycled fluorescent derivatives. Then samples were diluted, filtered and directly injected, thus avoiding extraction steps. The analytes were resolved using a mobile phase containing 0.08 M SDS-4.5% butanol at pH 3 running at 1.5 mL/min through a C18 column at 40°C, without interferences from endogenous compounds in plasma. Excitation and emission wavelengths were 260 and 380 nm, respectively. The chromatographic analysis time was less than 40 min. The analytical methodology was validated following the International Conference on Harmonization of Technical Requirements for Registration of Pharmaceuticals for Human Use (ICH) guidelines in terms of: selectivity, linear range (0.3-15 μg/mL), linearity (r(2)>0.999), sensitivity (LOD, 65-80 ng/mL; LOQ, 165-200 ng/mL), intra- and interday accuracy (-12.2-11.5%) and precision (<9.2%) and robustness (<6.3%). The method was used to quantify the tamoxifen and tamoxifen derivatives in several breast cancer patients from a local hospital, in order to study the correlation between the genotype of the patient and the ability to metabolize tamoxifen.
authors.affiliation: Química Bioanalítica, QFA, ESTCE, Campus Riu Sec, Universitat Jaume I, 12071 Castelló, Spain. Electronic address: vicentej@uji.es.
authors.forename: Juan
authors.initials: J
authors.lastname: Peris-Vicente
authors.affiliation: Biopatologia Molecular, Hospital Provincial, Dr. Clara, 12003 Castelló, Spain.
authors.forename: Enrique
authors.initials: E
authors.lastname: Ochoa-Aranda
authors.affiliation: Department of Criminology and Forensic Sciences, Dr. H. S. Gour University, 470003 Sagar, India.
authors.forename: Devasish
authors.initials: D
authors.lastname: Bose
authors.affiliation: Química Bioanalítica, QFA, ESTCE, Campus Riu Sec, Universitat Jaume I, 12071 Castelló, Spain.
authors.forename: Josep
authors.initials: J
authors.lastname: Esteve-Romero
mesh_terms: D018931:Antineoplastic Agents, Hormonal / Q000097:blood; D001943:Breast Neoplasms / Q000097:blood*; D002853:Chromatography, Liquid / Q000379:methods*; D005260:Female; D005453:Fluorescence; D006801:Humans; D057230:Limit of Detection; D008823:Micelles; D013629:Tamoxifen / Q000031:analogs & derivatives* / Q000097:blood*
chemical_list: D018931:Antineoplastic Agents, Hormonal; D008823:Micelles; D013629:Tamoxifen; C016601:afimoxifene; C055492:4-hydroxy-N-desmethyltamoxifen; C035830:tamoxifen N-oxide; C028787:N-desmethyltamoxifen
keywords: Genotype; Metabolization; Micellar liquid chromatography; Plasma; Tamoxifen