MICELLAR ELECTROKINETIC CAPILLARY CHROMATOGRAPHY OF HEMATOPORPHYRIN, PROTOPORPHYRIN AND THEIR COPPER AND ZINC-COMPLEXES

The micellar electrokinetic chromatographic separation of haematoporphyrin IX (HP) and protoporphyrin IX (PP) in the forms of free acids and of metal complexes with zinc or copper is successful in a mixture of a micellar solution of sodium dodecyl sulphate (SDS) at pH 11 and dimethylformamide (10:2, v/v). All the porphyrins migrate in the direction of the electric field, i.e., from the positive end towards the grounded end of the capillary. The migration time of each porphyrin increases with increasing concentration of DMF in the carrier solution. The capacity factor calculated for the distribution of each porphyrin compound between the SDS micelles and the bulk solution varies nearly linearly with the concentration of the SDS micelles. The migration sequence, that is, the increasing order of migration time, for the porphyrins is Zn(HP) < H2HP < Cu(HP) < Zn(PP) < H2PP < Cu(PP).