Simplified assay method for measuring 3-methoxy-4-hydroxy mandelic acid in human urine.

Abstract

A simplified and accurate assay method for measuring 3-methoxy-

Determination of vanillylmandelic acid in urine by use of catalytic maximum wave in differential pulse polarography

“…This means that this method has excellent characteristics and selectivity. technique for eluting solutes with a wide range of polarity, for improving solute detectability, and for increasing the speed of analysis (5). However, the miniaturization of devices that can produce precise and accurate gradients is not a simple matter.…”

“…The solvents delivered by two pumps should be mixed in a static or dynamic mixer if sensitive solute detection is needed (7)(8)(9). However, these gradient instruments are not readily available, and they are expensive (5). Therefore, a considerable effort was made toward producing gradients for micro-HPLC in an indirect way by using a single high-pressure pump.…”

“…A number of techniques have been used to separate and identify metabolites such as VMA and HVA in urine. These metabolites have been analyzed by a colorimetric method (5) based on a rigorous color-development condition, but it is well-known that many substances existing in urine interfere with color development reaction. Also, a gas chromatographic method (6) requires nonvolatiles to form volatile derivatives.…”