title: High-performance liquid chromatography/atmospheric pressure chemical ionization mass spectrometric method for the analysis of catecholamines and metanephrines in human urine.
abstract: An assay of norepinephrine (NE), epinephrine (E), dopamine (DA), normetanephrine (NE) and metanephrine (MN) based on high-performance liquid chromatography (HPLC) in combination with atmospheric pressure chemical ionization mass spectrometry (APcI-MS) is described. The catecholamines and metanephrines were extracted from urine and aqueous samples using Bio-Rex 70 cation-exchange resin and subjected to analysis by HPLC/APcI-MS. The separation was performed on a C18 column in 50 mM ammonium formate buffer, pH 3.0, using a flow rate of 0.8 mL/min. Acetonitrile was added post-column at a flow rate of 0.2 mL/min via a post-column addition tee. The total analysis time was 6.5 min. The quantitative analysis was performed using 3,4-dihydroxybenzylamine (DHBA) as the internal standard (I.S.). Selected ion monitoring detection was applied: m/z 170 (for NE), 184 (for E and NM), 154 (for DA), 198 (for MN) and 140 (for DHBA, I.S.). The limits of quantitation were 5 ng/mL for NE, E and DA and 2.5 ng/mL for NM and MN. The recovery ranged from 75 to 83% for each analyte. The method was found to be simple and highly selective for the determination of catecholamines and metanephrines in the urine of patients suspected of pheochromocytoma.
authors.affiliation: Department of Pharmacy, National University of Singapore, Singapore.
authors.forename: E C
authors.initials: EC
authors.lastname: Chan
authors.forename: P C
authors.initials: PC
authors.lastname: Ho
mesh_terms: D001274:Atmospheric Pressure; D002021:Buffers; D002395:Catecholamines / Q000737:chemistry / Q000652:urine*; D002851:Chromatography, High Pressure Liquid / Q000379:methods*; D002852:Chromatography, Ion Exchange; D004298:Dopamine / Q000031:analogs & derivatives / Q000032:analysis / Q000737:chemistry / Q000652:urine; D004837:Epinephrine / Q000737:chemistry / Q000652:urine; D006801:Humans; D013058:Mass Spectrometry / Q000379:methods*; D008676:Metanephrine / Q000737:chemistry / Q000652:urine*; D015394:Molecular Structure; D009638:Norepinephrine / Q000737:chemistry / Q000652:urine; D009647:Normetanephrine / Q000737:chemistry / Q000652:urine; D012015:Reference Standards; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity
chemical_list: D002021:Buffers; D002395:Catecholamines; D009647:Normetanephrine; C022133:3,4-dihydroxybenzylamine; D008676:Metanephrine; D004298:Dopamine; D009638:Norepinephrine; D004837:Epinephrine