Post-column Fluorescence Derivatization Research Articles

High-performance liquid chromatographic method for the analysis of N tau-methylhistidine in food, chicken excreta, and rat urine.

A reliable high-performance liquid chromatographic method that utilizes a reversed-phase separation with ion-pairing and post-column fluorescence derivatization for the analysis of N tau-methylhistidine in food, chicken excreta, and rat urine is described. N tau-Methylhistidine in the hydrolyzed sample is first roughly separated from acid and neutral amino acids by an ion-exchange column. The N tau-methylhistidine fraction is then evaporated and the residue is dissolved in the mobile phase (15 mM sodium octane sulfonate in 20 mM potassium phosphate), and subjected to high-performance liquid chromatography.

Determination of N-methylcarbamate pesticides in well water by liquid chromatography with postcolumn fluorescence derivatization.

La sensibilite pour l'aldicarb et ses produits de transformation et six autres composes est de 1 ppb dans des eaux potables. La recuperation moyenne de 9 pesticides ajoutes a l'eau a des concentrations de 8 a 40 ppb est superieur a 95%

Design of a post-column fluorescence derivatization system for use with microbore columns

The design of a post-column fluorescence derivatization system utilizing microbore columns is discussed theoretically and investigated experimentally. The basic disadvantage with post-column derivatization systems is the introduction of additional band broadening that occurs in the flow-through reactor. In this paper, the band spreading in the reactor is limited by using a zig-zag open-tubular capillary, where plate height decreases with the square of the capillary diameter. It is shown that adequate mixing of two liquid streams can be achieved with a special 30-nl volume mixing chamber. Some of the reactor design parameters are, by necessity, based on the model fluorescence derivatization reaction employed; in this case, a modification of the very fast o-phthaldialdehyde reaction with primary amines is reported which incorporates the use of 3-mercaptopropionic acid. The consideration of the minimum allowable residence time and the minimum band spreading in the reactor and the mixing chamber allows calculation of the reactor geometry. Theoretical investigation of the reactor design allows prediction of the general rules for the system optimization. The application of the system to analysis of amino acids and primary aliphatic amines, which were separated on an octadecyl-silica reversed-phase column, is demonstrated. Advantages and disadvantages of the system are discussed.

Profiling of urinary medium-sized peptides in normal and uremic urine by high-performance liquid chromatography

This report describes the profiling of medium-sized peptides in both normal and uremic urine by ion-pair reversed-phase high-performance liquid chromatography using an acetonitrile—heptafluorobutyric acid solvent system as eluent. Several medium-sized peptide peaks could be detected in both normal and uremic urine at low picomole level by using post-column fluorescence derivatization with fluorescamine. Contrary to expectation, uremic urine contained slightly larger amounts of medium-sized peptides compared with normal urine.

Post-column fluorescence derivatization of peptides : Problems and potential in high-performance liquid chromatography

Some critical parameters such as the pumping system, mixing devices and detector design in instrumentation for post-column derivatization in high-performance liquid chromatography are discussed. The derivatization was studied with pharmaceutically important nona-peptides containing primary amino groups which react with Fluram ® and reaction parameters such as pH, solvent and reagent concentration were investigated. Both adsorption systems and reversed-phase systems were used to separate the peptides prior to the post-column reaction. Reversed-phase chromatography has the advantage of simpler sample preparation, better reaction control and optimization of solvent conditions. As a result, detection limits of between 5 and 10 ng per injection can be obtained and the reproducibility of the results is better than ±2% (relative standard deviation). The method has been applied to the analysis of injection solutions (ampoules).