title: Micellar electrokinetic chromatography for the determination of cortisol in urine samples in view of biomedical studies.
abstract: An MEKC method used for the determination of cortisol in urine was developed and elaborated. In turn, the measurements of urinary free cortisol provided the diagnostic information for excess adrenal production of cortisol. MEKC realized by the addition of anionic surfactant SDS to the buffer solution was demonstrated to be the appropriate mode for the separation of cortisol and dexamethasone was used as internal standard. A buffer solution composed of 10 mM sodium tetraborate and 50 mM SDS at pH 8.8 was used. The MEKC assay was evaluated by analyzing a series of urine samples containing cortisol in variable concentrations. The proposed method was validated for specificity, linearity, LODs and LOQs, precision and trueness. The LOQ for cortisol equaled 5 ng/mL. The method was selective and reliable for identification and can detect changes of endogenous levels of cortisol in urine under different stress situations.
authors.affiliation: Department of Pharmaceutical Chemistry, Medical University of Gdańsk, Gdańsk, Poland. ilona@gumed.edu.pl
authors.forename: Ilona
authors.initials: I
authors.lastname: Oledzka
authors.forename: Alina
authors.initials: A
authors.lastname: Plenis
authors.forename: Lucyna
authors.initials: L
authors.lastname: Konieczna
authors.forename: Piotr
authors.initials: P
authors.lastname: Kowalski
authors.forename: Tomasz
authors.initials: T
authors.lastname: Baczek
mesh_terms: D020374:Chromatography, Micellar Electrokinetic Capillary / Q000379:methods*; D006801:Humans; D006854:Hydrocortisone / Q000652:urine*; D057230:Limit of Detection; D012967:Sodium Dodecyl Sulfate
chemical_list: D012967:Sodium Dodecyl Sulfate; D006854:Hydrocortisone