Study of peptide/metal-core interaction in capillary columns covalently modified with deuteroporphyrins

YONE A; GRELA D; GARCÍA MB; VIZIOLI NM

Florianópolis

Simposio; 16th Symposium on Biomedical, Biopharmaceutical and Industrial Applications of Capillary Electrophoresis and Microchip Technology; 2010

After mapping the genomes of several species, including the human genome, the mapping of the proteome is one of the most ambitious research projects mankind has ever undertaken. In this context, the growing importance of microseparation techniques, is expected to provide a valuable alternative to conventional slab-gel electrophoresis or HPLC in terms of speed, reagent consumption and efficiency. CE and CEC have demonstrated a broad applicability in the field of aminoacid, peptide and protein separations by development of different modes of both techniques. In the present work, a mixture of bioactive peptides (bradykinin, angiotensin I, luteinizing hormone releasing hormone, angiotensin II, oxytocin, and methionine-enkephalin) was analyzed by open tubular capillary electrochromatography (OTCEC). Separations were carried out in fused silica capillaries (50μm id x 32 cm long) covalently modified with different deuteroporphyrins (iron-, copper-, zinc-, and nickel-deuteroporphyrins). Optimization of running conditions was performed to obtain better resolution and peak shape. In all cases the running buffer consisted of a 25 mM potassium phosphate, pH 4.0, containing 5% acetonitrile and 10 mM of hydroquinone. The interaction between peptides and the metal-core was studied by comparison of peptide mobilities observed in different columns. The results obtained showed that different metal-core on the porphyrin and the spatial conformation of porphyrin attachment, traduce on differences in the analyte interaction with the stationary phase.