title: Determination of tamoxifen and its metabolites in human plasma by nonaqueous capillary electrophoresis with contactless conductivity detection.
abstract: A new approach for the quantification of tamoxifen and its metabolites 4-hydroxytamoxifen, N-desmethyltamoxifen, and 4-hydroxy-N-desmethyltamoxifen (endoxifen) in human plasma samples using NACE coupled with contactless conductivity detection (C4D) is presented. The buffer system employed consisted of 7.5 mM deoxycholic acid sodium salt, 15 mM acetic acid, and 1 mM 18-crown-6 in 100% methanol. The complete separation of all targeted compounds (including endoxifen racemate) could be achieved within 6 min under optimized conditions. The proposed method was validated and showed good linearity in the range from 100 to 5000 ng/mL with correlation coefficients between 0.9922 and 0.9973, LODs in the range of 25-40 ng/mL, and acceptable reproducibility of the peak area (intraday RSD 2.2-3.1%, n = 4; interday (3 days) RSD 6.0-8.8%, n = 4). The developed method was successfully demonstrated for the quantification of tamoxifen and its metabolites in human plasma samples collected from breast cancer patients undertaking tamoxifen treatment.
authors.affiliation: Centre for Sustainable Nanomaterials, Ibnu Sina Institute for Scientific and Industrial Research, Universiti Teknologi Malaysia, Johor, Malaysia.|Department of Chemistry, Faculty of Science, Universiti Teknologi Malaysia, Johor, Malaysia.
authors.forename: Lee Yien
authors.initials: LY
authors.lastname: Thang
authors.affiliation: Department of Biosciences and Health Sciences, Faculty of Biosciences and Medical Engineering, Universiti Teknologi Malaysia, Johor, Malaysia.
authors.forename: Shafinaz
authors.initials: S
authors.lastname: Shahir
authors.affiliation: Centre for Sustainable Nanomaterials, Ibnu Sina Institute for Scientific and Industrial Research, Universiti Teknologi Malaysia, Johor, Malaysia.|Department of Chemistry, Faculty of Science, Universiti Teknologi Malaysia, Johor, Malaysia.|Australian Centre for Research on Separation Science, School of Physical Sciences - Chemistry, University of Tasmania, Tasmania, Australia.
authors.forename: Hong Heng
authors.initials: HH
authors.lastname: See
keywords: Breast cancer; Contactless conductivity detection; Nonaqueous capillary electrophoresis; Plasma; Tamoxifen