title: On-column derivatization and analysis of amino acids, peptides, and alkylamines by anhydrides using capillary electrophoresis.
abstract: This work demonstrates the use of an in-capillary procedure for derivatization of amino acids, peptides, and alkylamines by anhydrides using capillary electrophoresis (CE). Migrating in an uncoated fused-silica capillary, plugs of substrate and anhydride are injected separately and electrophoresed. Differential transport velocities permit the separate zones to penetrate each other under an applied field, thereby facilitating reaction. In initial experiments the extent of reaction between tryptophan and acetic anhydride was examined and product amounts quantitated by CE. In separate experiments a series of amino acids and peptides were injected into the capillary and reacted with phthalic anhydride on-column to yield the phthalic derivatized species. Finally, on-column derivatization of alkylamines with phthalic anhydride was investigated and electrophoretic mobility related to molecular weight of the derivatized amines. These procedures illustrate the use of the capillary as a microreactor in the facile synthesis of derivatized molecules and ease of quantitation of reaction products under conditions of electrophoresis.
authors.affiliation: Department of Chemistry and Biochemistry, California State University, Los Angeles 90032-8202, USA.
authors.forename: Y
authors.initials: Y
authors.lastname: Zhang
authors.forename: F A
authors.initials: FA
authors.lastname: Gomez
mesh_terms: D000588:Amines / Q000032:analysis*; D000596:Amino Acids / Q000032:analysis*; D000812:Anhydrides; D019075:Electrophoresis, Capillary / Q000295:instrumentation / Q000379:methods; D004867:Equipment Design; D007202:Indicators and Reagents; D010455:Peptides / Q000032:analysis*
chemical_list: D000588:Amines; D000596:Amino Acids; D000812:Anhydrides; D007202:Indicators and Reagents; D010455:Peptides