Determination of polyhydroxy antibiotics by capillary zone electrophoresis with amperometric detection at a nickel electrode

Abstract Capillary zone electrophoresis (CZE) with amperometric detection at a nickel electrode for the determination of polyhydroxy antibiotics in alkaline solution is described. The electrode used was a 300 μm diameter Ni disk electrode operated in a wall-jet configuration. With a working potential of +0.54 V and an 80 cm capillary (o.d. 360 μm, i.d. 25 μm) at 15 kV in the electrophoretic medium of 0.10 mol/1 NaOH, a sample mixture containing seven different polyhydroxy antibiotics was separated within 20 min. The linearity varied over three orders of magnitude of concentration, the detection limit was 0.50 μmol/1, for doublemycin, and the relative standard deviation of the peak current was about 5.5% in a period of 8 h. The method has been successfully employed to the determination of the purity of kanamycin, and the content of amikacin in human urines.

[1]  S. Lunte,et al.  Chemically modified microelectrodes for capillary electrophoresis/electrochemistry , 1994 .

[2]  A. Ewing,et al.  Capillary electrophoresis in 2 and 5 microns diameter capillaries: application to cytoplasmic analysis. , 1990, Analytical chemistry.

[3]  Richard N. Zare,et al.  Determination of carbohydrates by capillary zone electrophoresis with amperometric detection at a copper microelectrode , 1993 .

[4]  R. Baldwin,et al.  Determination of carbohydrates, sugar acids and alditols by capillary electrophoresis and electrochemical detection at a copper electrode , 1994 .

[5]  Theodore Kuwana,et al.  Nickel-titanium alloy electrode as a sensitive and stable LCEC detector for carbohydrates , 1994 .

[6]  K. Korinek,et al.  The oxidation of organic compounds at a nickel anode in alkaline solution , 1971 .

[7]  A. Ewing,et al.  Capillary zone electrophoresis with electrochemical detection in 12.7 microns diameter columns. , 1988, Analytical chemistry.

[8]  R. Baldwin,et al.  Amperometric detection in capillary electrophoresis with normal size electrodes , 1993 .

[9]  Richard P. Baldwin,et al.  Determination of amino acids and peptides by capillary electrophoresis and electrochemical detection at a copper electrode , 1994 .

[10]  R. Zare,et al.  End-column detection for capillary zone electrophoresis. , 1991, Analytical chemistry.

[11]  S. Lunte,et al.  Selective detection of free thiols by capillary electrophoresis-electrochemistry using a gold/mercury amalgam microelectrode , 1993 .

[12]  G. Mancini,et al.  Quantitative determination and separation of analogues of aminoglycoside antiobiotcs by high-performance liquid chromatography , 1985 .