Analysis of Mixed Drugs by Mass Spectrometry. XIII

Food Additives(3). Quantitative Determination of Ethyl p-hydroxybenzoate.

Abstract

Quantitative analysis of ethyl p-hydroxybenzoate by means of mass spectrometry was established by using benzoic acid as an internal standard. Thus, the amount of ethyl p-hydroxybenzoate can be calculated from the ratio of the peak hights of m/e 121(base peak, ethyl p-hydroxybenzoate)to m/e 105(base peak, benzoic acid), as the ratio was found to be proportional to the amount of ethyl phydroxybenzoate. This method made possible to determine ethyl p-hydroxybenzoate between 40 μg and 200μg within the error of±3%.