Analysis of urinary 3-methoxy-4-hydroxyphenylglycol by high-performance liquid chromatography and electrochemical detection

A high-performance liquid chromatographic method with electrochemical detection for the quantitation of total 3-methoxy-4-hydroxyphenylglycol (MHPG) in human urine is described. Existing methods for deconjugation and extraction have been optimized. The present method is simpler than existing methods with a high precision. Urinary MHPG is deconjugated enzymatically and subsequently extracted with ethyl acetate. The organic layer is extracted with acetic acid and a sample of the aqueous layer is injected into a reversed-phase column. In one run 90 samples can be processed. The critical parameters of deconjugation, extraction and chromatography are described. Data for reproducibility and selectivity are presented.