Determination of monoamine neurotransmitters and metabolites by high-performance liquid chromatography based on Ag(III) complex chemiluminescence detection

Abstract

A novel, simple and efficient chemiluminescence system has been developed for the determination of monoamine neurotransmitters and metabolites. By using the Ag (III)-luminol chemiluminescence system as a detector, a high performance liquid chromatography chemiluminescence method (HPLC-CL) was established and used to detect seven monoamine neurotransmitters. Under the optimized conditions, the detection limits (3S/N) of epinephrine (E), levodopa (l-DOPA), dopamine (DA), serotonin (5-HT), 3-methoxy-4-hydroxyphenylglycol (MHPG), 3,4-dihydroxyphenylacetic acid (DOPAC) and 5-hydroxypentylacetic acid (5-HIAA) were 20.0 μg dm^-3,15.0 μg dm^-3, 15.0 μg dm^-3, 8.0 μg dm^-3, 2.0 μg dm^-3, 2.0 μg dm^-3 and 3.0 μg dm^-3, respectively. Moreover, they were well within the linear range of 50-1000 μg dm^-3, 50-1000 μg dm^-3, 50-1000 μg dm^-3, 25-1000 μg dm^-3, 5-25 μg dm^-3, 5-25 μg dm^-3 and 10-30 μg dm^-3, respectively. The average recovery varied between 84.82% and 110.4%. The method has the attributes of simplicity, high sensitivity, and high efficiency. The sensitization and inhibition mechanisms for luminol-[Ag(HIO₆)₂]^5-- analytes CL system were proposed by CL spectra and free-radical capture experiment.

Keywords: Chemiluminescence; High-performance liquid chromatography; Luminol-[Ag(HIO(6))(2)](5-); Mechanism; Metabolites; Monoamine neurotransmitter.