title: Determination of tobramycin in human serum by capillary electrophoresis with contactless conductivity detection.
abstract: A study on the determination of the antibiotic tobramycin by CE with capacitively coupled contactless conductivity detection is presented. This method enabled the direct quantification of the non-UV-absorbing species without incurring the disadvantages of the indirect approaches which would be needed for optical detection. The separation of tobramycin from inorganic cations present in serum samples was achieved by optimizing the composition of the acetic acid buffer. Field-amplified sample stacking was employed to enhance the sensitivity of the method and a detection limit of 50 microg/L (S/N = 3) was reached. The RSDs obtained for migration time and peak area using kanamycin B as internal standard were typically 0.12 and 4%, respectively. The newly developed method was validated by measuring the concentration of tobramycin in serum standards containing typical therapeutic concentrations of 2 and 10 mg/L. The recoveries were 96 and 97% for the two concentrations, respectively.
authors.affiliation: Department of Chemistry, National University of Singapore, Republic of Singapore.
authors.forename: Wai Siang
authors.initials: WS
authors.lastname: Law
authors.forename: Pavel
authors.initials: P
authors.lastname: Kubán
authors.forename: Ling Ling
authors.initials: LL
authors.lastname: Yuan
authors.forename: Jian Hong
authors.initials: JH
authors.lastname: Zhao
authors.forename: Sam Fong Yau
authors.initials: SF
authors.lastname: Li
authors.forename: Peter C
authors.initials: PC
authors.lastname: Hauser
mesh_terms: D019342:Acetic Acid; D000900:Anti-Bacterial Agents / Q000097:blood*; D001774:Blood Chemical Analysis / Q000379:methods* / Q000706:statistics & numerical data; D004553:Electric Conductivity; D019075:Electrophoresis, Capillary / Q000379:methods* / Q000706:statistics & numerical data; D006801:Humans; D007612:Kanamycin / Q000031:analogs & derivatives / Q000097:blood; D012680:Sensitivity and Specificity; D014031:Tobramycin / Q000097:blood*
chemical_list: D000900:Anti-Bacterial Agents; C001495:bekanamycin; D007612:Kanamycin; D019342:Acetic Acid; D014031:Tobramycin