Capillary electrochromatographic separation of aromatic amino acids possessing peptides using porphyrin derivatives as the inner wall modifiers.
Two different porphyrin derivatives (H2TPP(m-OPh)4 and Rh(III)TPP(m-OPh)4) were investigated with respect to their capability to help resolution of five model aromatic peptides in capillary electrophoresis/open tubular capillary electrochromatography. Though the main separation mechanism was preferentially based on the ionic properties of the separated analytes, involvement of particularly H2TTPP(m-OPh)4-peptide interactions at alkaline pH (8.0) was clearly demonstrated. In combination with Tris-phosphate buffer, a speed up of the separation was observed at pH 2.25 (particularly if Rh(III)TPP(m-OPh)4 was used as capillary coating); in spite of the speed up of the separation the selectivity of the system was sufficient and resulted in a complete separation of the five model peptides. It can be expected that Rh(III)TPP(m-OPh)4 capillary coating in combination with Tris-phosphate buffer can be generally used for a considerable speeding up of lengthy separations of peptides in acidic media with some decrease in the separation power of the system.
Charvátová
Jana
J
Department of Analytical Chemistry, Institute of Chemical Technology Prague, Czech Republic.
Král
Vladimír
V
Deyl
Zdenek
Z
D024322:Amino Acids, Aromatic / Q000032:analysis*; D020374:Chromatography, Micellar Electrokinetic Capillary / Q000379:methods*; D010455:Peptides / Q000737:chemistry / Q000302:isolation & purification*; D011166:Porphyrins / Q000737:chemistry*
D024322:Amino Acids, Aromatic; D010455:Peptides; D011166:Porphyrins