title: The use of liquid membranes in the multi-residue extraction of stilbenes in a variety of biological matrices and their detection with LC-ES-MS.
abstract: Supported liquid membrane (SLM) has been used as a sample preparation method in the simultaneous extraction of a mixture of three stilbene compounds in cow's milk, urine, bovine kidney and liver tissues matrices. The stilbene compounds analysed included, dienestrol, diethylstilbestrol and hexestrol. The liquid membrane used for trapping these compounds consisted of 5% tri-n-octylphosphine oxide (TOPO) dissolved in di-n-hexylether/n-undecane (1:1). The extraction efficiencies obtained after enrichment of 1 ng/L stilbenes in variety of biological matrices of milk, urine, liver, kidney and water, ranged from 60 - 70%, 71 - 86%, 69 - 80%, 63 - 7A% and 72 - 93% respectively. The detection limits obtained from urine extraction were 2.1 ng/L, 1.3 ng/L and 3.0 ng/L; from liver and kidney tissues were 2.9 ng/L, 1.6 ng/L and 3.8 ng/L and from milk was 3.2 ng/L, 2.5 ng/L and 4.3 ng/L for hexestrol, dienestrol and diethylstilbestrol respectively.
authors.affiliation: School of Chemistry, Faculty of Science and Agriculture, University of KwaZulu-Natal, Durban 4001 South Africa. msagati@ukzn.ac.za
authors.forename: Titus Alfred Makudali
authors.initials: TA
authors.lastname: Msagati
authors.forename: Mathew Muzi
authors.initials: MM
authors.lastname: Nindi
mesh_terms: D000818:Animals; D002417:Cattle; D002853:Chromatography, Liquid; D007668:Kidney / Q000737:chemistry; D008099:Liver / Q000737:chemistry; D008892:Milk / Q000737:chemistry; D009943:Organophosphorus Compounds / Q000737:chemistry; D015203:Reproducibility of Results; D021241:Spectrometry, Mass, Electrospray Ionization; D013267:Stilbenes / Q000032:analysis* / Q000652:urine
chemical_list: D009943:Organophosphorus Compounds; D013267:Stilbenes; C044965:trioctyl phosphine oxide