Chemiluminescent detection of catecholamines by generation of hydrogen peroxide with imidazole.

A novel detection method for catecholamines using imidazole was investigated using a chemiluminescence coupled flow injection system. Imidazole catalysed decomposition of catecholamines to generate hydrogen peroxide, then the hydrogen peroxide was detected by chemiluminescence. The optimal condition for generation of hydrogen peroxide from a catecholamine was to incubate the catecholamines (53 pmol) in an imidazole solution (50 mmol/L, pH 9.

Amines for detection of dopamine by generation of hydrogen peroxide and peroxyoxalate chemiluminescence.

A range of nitrogen-containing compounds (alkyl amines, piperazines, cyclohexylamines and nitrogen heterocyclics) were investigated for generation of hydrogen peroxide from dopamine and detection by peroxyoxalate chemiluminescence. Imidazole, ethyleneurea and allantoin among the nitrogen heterocyclic compounds tested generated hydrogen peroxide from dopamine following incubation at 60 degrees C, pH 9.5-10.

Detection of substances with alcoholic or phenolic hydroxyl groups by generation of hydrogen peroxide with imidazole and peroxyoxalate chemiluminescence.

On-line detection of substances with an alcoholic or phenolic hydroxyl group using imidazole and peroxyoxalate chemiluminescence was investigated qualitatively using a flow-injection method. The substances tested included six polyphenols, five monophenols and six sugars. After incubation at 80 degrees C with an imidazole buffer (pH 9.

High-performance liquid chromatographic determination of plasma and brain histamine without previous purification of biological samples: cation-exchange chromatography coupled with post-column derivatization fluorometry.

A highly sensitive and specific method was developed for the determination of histamine in biological materials by high-performance liquid chromatography with a cation exchanger and an automated Shore's fluorometric detection system. Since substances causing interference in Shore's o-phthalaldehyde method, such as ammonia, histidine, spermine and spermidine, were completely separated on the column and their fluorescent intensities were much less than that of histamine in this detection system, histamine could be determined by injecting a perchloric acid extract of human plasma or mouse brain tissue directly onto the column without any previous purification procedure. The lower limit of detection of histamine by this method is 0.