Abstract
Purpose: The aim of the
study was the characterization of the electrophoretic behavior of
cephalosporins from different generation having different structural
characteristics in order to develop a rapid, simple and efficient capillary
electrophoretic method for their identification and simultaneous separation
from complex mixtures.
Methods: Ten
cephalosporin derivatives (cefaclor, cefadroxil, cefalexin, cefazolin,
cefoxitin, cefuroxime, cefoperazone, cefotaxime, ceftazidime, ceftriaxone) were
analyzed by capillary zone electrophoresis using different background
electrolyte solutions at different pH values. Electrophoretic mobilities of the
analytes were calculated, the influence of the electrophoretic parameteres on
the separation was established and the analytical conditions were optimized.
Results: Taking into
consideration their structural and chemical properties cephalosporins can be
detected over a pH range between 6 and 10. The best results were obtained using
a buffer solution containing 25
mM disodium hydrogenophosphate - 25 mM sodium dihydrogenophosphate, at a pH –
7.00, + 25 kV voltage at a temperature of 25 °C, UV detection at 210 nm. Using the
optimized analytical conditions we achieved the simultaneous baseline
separation for seven cephalosporins in less then 10 minutes.
Conclusion: Using the described optimized
electrophoretic procedures, capillary electrophoresis can be used for the
identification and determination of cephalosporins in formulated pharmaceutical
products and for their separation from complex mixtures.