Determination of urinary vanillactic acid and plasma dihydroxyphenylalanine as markers of non-secreting neuroblastoma by high-performance liquid chromatography with electrochemical detection.
An accurate and precise isocratic high-performance liquid chromatographic technique for the analysis of urinary vanillactic acid (VLA) and plasma dihydroxyphenylalanine (DOPA), especially at low concentrations (pmol/l) for VLA and nmol/l for DOPA), is described. The compounds were purified in a single step, (on an anion exchanger for VLA and on aluminium oxide for DOPA), separated by ion-pair reversed-phase liquid chromatography, and detected electrochemically. A single analysis was complete within 18 min. Mean recoveries of 103 and 81% were obtained for VLA and DOPA, respectively, and the limits of detection were 42 and 76 pmol/l, respectively. The mean values of the intra-assay coefficient of variation were 14 and 7.1% for VLA and DOPA, respectively, and the mean values of the inter-assay coefficient of variation were 15.7 and 11.6%, respectively. Modifications of the retention times (between 2 and 42 min) induced by changes in the eluent were determined. Reference values for normal children and children with neuroblastoma or various tumours are given.
Jouve
J
J
Laboratoire de Biochimie Médicale et INSERM U316, CHU de Tours, France.
Bakri
D
D
Herault
J
J
Muh
J P
JP
D000293:Adolescent; D014408:Biomarkers, Tumor; D002648:Child; D002675:Child, Preschool; D002851:Chromatography, High Pressure Liquid; D004032:Diet; D004295:Dihydroxyphenylalanine / Q000097:blood*; D004563:Electrochemistry; D004566:Electrodes; D006719:Homovanillic Acid / Q000031:analogs & derivatives* / Q000652:urine; D006801:Humans; D006863:Hydrogen-Ion Concentration; D007202:Indicators and Reagents; D007223:Infant; D007231:Infant, Newborn; D009423:Nervous System Neoplasms / Q000097:blood / Q000175:diagnosis* / Q000652:urine; D009447:Neuroblastoma / Q000097:blood / Q000175:diagnosis* / Q000652:urine; D012015:Reference Standards
D014408:Biomarkers, Tumor; D007202:Indicators and Reagents; C003753:vanillactic acid; D004295:Dihydroxyphenylalanine; D006719:Homovanillic Acid