MICELLAR ELECTROKINETIC CHROMATOGRAPHY OF HIGHLY HYDROPHOBIC PEPTIDES

A micellar electrokinetic chromatography (MEKC) separation method was developed for analysis of highly hydrophobic derivatized peptides that are able to reverse multidrug resistance (MDR) observed in chemothera py of human tumors. The hydrophobicity of these peptides was character ized by the retention factor (k(MEKC)') obtained by MEKC and by the k( HPLC)' obtained by reversed phase high performance liquid chromatograp hy (RP-HPLC). A tendency was observed between the log k(MEKC)' values of the peptides investigated and their capabilities to reverse MDR. Th e higher the k(MEKC) value of the peptide, the higher its hydrophobici ty and the higher was its capability to reverse MDR. This result was i n accordance with that obtained by RP-HPLC. Therefore, the effect of t he peptides on MDR could be estimated on the basis of their log k(MEKC )' values. (C) 1998 Elsevier Science B.V. All rights reserved.