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.
Laboratoire de Biochimie Médicale et INSERM U316, CHU de Tours, France.
J
J
Jouve
D
D
Bakri
J
J
Herault
J P
JP
Muh
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