Fractionation of the human recombinant tissue plasminogen activator (rtPA) glycoforms by high-performance capillary zone electrophoresis and capillary isoelectric focusing.

This paper reports the fractionation of recombinant human tissue plasminogen activator (rtPA) glycoforms, a complex mixture to demonstrate the high resolving power of capillary zone electrophoresis (CZE) and capillary isoelectric focusing (cIEF). rtPA is a glycoprotein with a complex carbohydrate structure. The electropherograms and IEF patterns have been discussed in light of the known carbohydrate structures of rtPA. rtPA was treated with neuraminidase which removes the sialic acids from the carbohydrate chains. The desialylated rtPA was analyzed by both CZE and IEF and the results were compared to those of untreated rtPA. The usefulness of CZE and cIEF in the characterization of glycoproteins proteins is also discussed.