Application of a novel cation-exchange reagent, Igepon T-77 (N-methyl oleoyl taurate), to microbore separations of alumina extracts of catecholamines from cerebrospinal fluid, plasma, urine and brain tissue with amperometric detection

Abstract

The use of a novel amide surfactant, N-methyl oleoyl taurate (Igepon T-77), has been examined for the separation of amines on reversed-phase chromatographic material. This reagent was found to partition onto the C 18 material in a partially irreversible and concentration independent manner. When the stationary phase is saturated with this surfactant, the loaded column performs as a strong cation exchanger. Novel separations are possible as a result of secondary hydrogen-bonding effects which modify classical retention order for primary, secondary and tertiary amines. Sensitive and selective applications of these separations are demonstrated for catecholamine determinations in blood plasma, cerebrospinal fluid, urine and brain tissue. Additional sensitivity is obtained for epinephrine by taking advantage of the pH-dependent intramolecular cyclization and on-column concentration of large injection volumes.