Determination of Acidic Metabolites of Biogenic Amines in Human Aqueous Humour by Gas Chromatography‐Negative Ion Chemical Ionisation Mass Spectrometry

Abstract

The concentrations of acidic metabolites derived from the biogenic amines o-, m-, and p-tyramines (o-, m-, and p-hydroxyphenylacetic acids), p-octopamine/p-synephrine (p-hydroxymandelic acid), and dopamine (homovanillic acid and 3,4-dihydroxyphenylacetic acid) were measured in human aqueous humour obtained from patients undergoing elective surgery for cataract removal or for trabeculectomy as a treatment for chronic open-angle glaucoma. There were no clear differences in the pattern of metabolism of neurotransmitters between the two groups. An unexpected finding was that the o-tyramine metabolite, o-hydroxyphenylacetic acid, was present in aqueous humour.

Using Chemical Derivatization to Determine the Human Urinary Acidic Catecholamine Metabolites Quantitatively by Liquid Chromatography/Electrospray Ionization‐Tandem Mass Spectrometry

“…1,2 Homovanillic acid (HVA), vanillymandelic acid (VMA), 3,4-dihydroxymandelic acid (DOMA) and 3,4-dihydroxyphenylacetic acid (DOPAC) are the main acidic metabolites of catecholamines, which was often tested in urine for monitoring the response to therapy in patients with phaeochromocytoma, psychosis and other related diseases and for neurologic diagnosis. 3,4 The widely used methods were based on GC, LC, capillary electrophoresis, coupled with mass spectrometric, [5][6][7][8][9] fluorescence, [10][11][12] and electrochemical detection. [13][14][15] LC-MS/MS technologies have revolutionized chemical and biological samples analysis, especially with electrospray ionization methods.…”