Micellar electrokinetic chromatography separations of dynorphin peptide analogs

Abstract

Prodynorphin is a precursor that has multiple cleavage sites to release various dynorphin opioid peptides. The dynorphin analogs used in this study have 18 amino acid residues. A series of dynorphin-like peptides, differing by a single residue (alanine substitution) were assembled by Fmoc solid-phase procedures and purified by preparative high performance liquid chromatography (HPLC). Separation of the Ala-scan dynorphin analogs was investigated by micellar electrokinetic chromatography (MEKC) employing anionic, cationic and zwitterionic surfactants. The role of electrostatic and hydrophobic forces in analyte-surfactant interactions is discussed with respect to the observed elution patterns. Separation of all dynorphin analogs by MEKC using a zwitterionic surfactant shows this technique to be powerful for separating closely related peptide species. It also demonstrates the potential for using MEKC for the prescreening of peptide libraries to determine their biological activity toward specific receptors. Results from the separation of dynorphin analogs by free solution and ion-pairing capillary electrophoresis are also presented.

Capillary Electrophoresis for the Analysis of Biopolymers

“…Relatively few applications have been found using MECC for protein separation. MECC is well suited for separation of peptides that have similar structures and electrophoretic mobilities (24,25). Depending on the electrostatic and hydrophobic interactions of analyte and surfactant, anionic, cationic, and zwitterionic surfactants can be chosen to optimize the resolution of peptides (24).…”

“…MECC is well suited for separation of peptides that have similar structures and electrophoretic mobilities (24,25). Depending on the electrostatic and hydrophobic interactions of analyte and surfactant, anionic, cationic, and zwitterionic surfactants can be chosen to optimize the resolution of peptides (24). The metabolism of the neuropeptide substance P has been investigated using MECC to analyze the degraded products after its incubation with bovine brain microvessel endothelial cells, which is a cell culture model of the blood-brain barrier (26).…”

Rapid methods for the separation of natural mixtures of beauverolides, cholesterol acyltransferase inhibitors, isolated from the fungus Isaria fumosorosea

“…It allows the partitioning of analytes between the aqueous phase and the micellar pseudostationary phase, which allows the neutrally charged compounds to be separated as long as they differ in hydrophobicity . Several other examples of the use of MEKC for the analysis of hydrophobic peptides were provided .…”

QUANTITATIVE ANALYSIS OF THE BACILLUS CEREUS EMETIC TOXIN, CEREULIDE, USING MICELLAR ELECTROKINETIC CHROMATOGRAPHY‐CAPILLARY ELECTROPHORESIS

“…Of particular relevance to the present study, MEKC‐CE has been used in several studies to analyze hydrophobic peptides (Idei et al. 1998; Fürtös‐matei et al. 2000; Gong et al.…”