title: Dispersive liquid-liquid microextraction based on solidification of floating organic drop combined with field-amplified sample injection in capillary electrophoresis for the determination of beta(2)-agonists in bovine urine.
abstract: Dispersive liquid-liquid microextraction based on solidification of floating organic drop (DLLME-SFO) was for the first time combined with field-amplified sample injection (FASI) in CE to determine four β(2)-agonists (cimbuterol, clenbuterol, mabuterol, and mapenterol) in bovine urine. Optimum BGE consisted of 20 mM borate buffer and 0.1 mM SDS. Using salting-out extraction, β(2)-agonists were extracted into ACN that was then used as the disperser solvent in DLLME-SFO. Optimum DLLME-SFO conditions were: 1.0 mL ACN, 50 μL 1-undecanol (extraction solvent), total extraction time 1.5 min, no salt addition. Back extraction into an aqueous solution (pH 2.0) facilitated direct injection of β(2)-agonists into CE. Compared to conventional CZE, DLLME-SFO-FASI-CE achieved sensitivity enhancement factors of 41-1046 resulting in LODs in the range of 1.80-37.0 μg L(-1). Linear dynamic ranges of 0.15-10.0 mg L(-1) for cimbuterol and 15-1000 μg L(-1) for the other analytes were obtained with coefficients of determination (R(2)) ≥ 0.9901 and RSD% ≤5.5 (n = 5). Finally, the applicability of the proposed method was successfully confirmed by determination of the four β(2)-agonists in spiked bovine urine samples and accuracy higher than 96.0% was obtained.
authors: Department of Analytical Chemistry, Faculty of Pharmacy, Gazi University, Ankara, Turkey.
authors: Murat Faruk
authors: MF
authors: Us
authors: Usama
authors: U
authors: Alshana
authors: Ibrahim
authors: I
authors: Lubbad
authors: Nilgün G
authors: NG
authors: Göğer
authors: Nusret
authors: N
authors: Ertaş
mesh_terms: D015078:2-Hydroxyphenethylamine / Q000031:analogs & derivatives / Q000652:urine; D058666:Adrenergic beta-2 Receptor Agonists / Q000652:urine*; D000814:Aniline Compounds / Q000652:urine; D000818:Animals; D002417:Cattle; D002976:Clenbuterol / Q000031:analogs & derivatives / Q000652:urine; D019075:Electrophoresis, Capillary / Q000379:methods*; D006863:Hydrogen-Ion Concentration; D059627:Liquid Phase Microextraction / Q000379:methods*; D012680:Sensitivity and Specificity; D012997:Solvents
chemical_list: D058666:Adrenergic beta-2 Receptor Agonists; D000814:Aniline Compounds; D012997:Solvents; C583263:cimbuterol; C583264:mapenterol; D015078:2-Hydroxyphenethylamine; C044573:mabuterol; D002976:Clenbuterol