Thesis Type: Doctorate
Institution Of The Thesis: Gazi University, Turkey
Approval Date: 2018
Thesis Language: Turkish
Student: Tenzile Zilhan Çabuk
Supervisor: NİLGÜN GÜNDEN GÖĞER
Abstract:A new, efficient, quick and alternative method has been developed, optimized and validated for the simultaneous determination of some acidic and basic doping substances (Procaine, Isoxsuprine, Nikethamide, Chlorpromazine and Flufenamic acid) in horse urine by dispersive liquid-liquid microextraction in combination with high-performance liquid chromatograpy tandem mass spectrometry. The reversed-phase chromatographic separation was obtained with a column Zorbax SB-C18 extended (150x3 mm; 3,5 μm; 80 Å) in gradient elution mode using distilled water-0.1% formic acid (v/v) and methanol-0.1% formic acid (v/v). Horse urine samples were analyzed by the multiple reaction monitoring (MRM) in the positive ion mode for Procaine, Isoxsuprine, Nikethamide, Chlorpromazine and negative ion mode for Flufenamic acid. Best results were obtained by use of 110 V for Isoxsuprine and Chlorpromazine, 80 V for Procaine and Nikethamide, 100 V for Flufenamic acid as fragmentor voltage. Under optimum dispersive liquid-liquid microextraction conditions, pH of the horse urine samples was adjusted 6. Acetonitrile (900.0 μL) and sodium chloride (20%) were added. Chloroform (80.0 μL) was used as extraction solvent. LOD values were found as 0.07 ng/mL for Procaine, 0.06 ng/mL for Isoxsuprine, 0.08 ng/mL for Nikethamide, 0.093 ng/mL for Chlorpromazine and 0.075 ng/mL for Flufenamic acid. After the evaluation of validation parameters for developed method, it was concluded that the method was selective, sensitive, precise, accurate and robust. Measurement uncertainty was calculated after validation of the method. Then the method was applied to the horse urine samples that was determined to contain Procaine, Isoxsuprine, Nikethamide, Chlorpromazine and Flufenamic acid.