Gas chromatographic determination of urinary 3-methoxy-4-hydroxyphenylethyleneglycol sulphate after its ion-pair extraction.

In order to develop a gas chromatographic method with flame ionization detection for the analysis of urinary 3-methoxy-4-hydroxyphenylethyleneglycol sulphate, a new procedure for its isolation has been introduced. The conjugated metabolite has been extracted by an ion-pair technique using tetrabutyl ammonium as counter ion and dichloromethane as organic solvent. Hydrolysis and derivatization of 3-methoxy-4-hydroxyphenylethyleneglycol sulphate have been finally performed by treatment with heptafluorobutyric anhydride. Each step of the procedure, applied to the analysis of urine samples both from normal subjects and from patients with neuroblastoma, has been discussed.