development of a method for the determination of 4-hydroxy-3-methoxymandelic acid (vanillylmandelic acid) in urine by paper chromatography

we have developed a simple and precise paper chromatographic method for the determination of 4-hydroxy-3-methoxymandelic acid (vma) in urine. concentrations of vma in patients with neuroblastoma were increased in comparison to controls. the linearity was excellent in the concentration range tested. the within-assay coefficient of variation for control and patient urine was less than 2.2%. the recovery was in the range of 97.9-99.4%. results from testing urine samples of controls and patients with neuroblastoma suggest that this method is a reliable and convenient system for quantification of vma in urine and can be used in the mass screening of neuroblastoma in infants. sample preparation requires minimal time and the entire procedure is completed within 5 h.