Liquid chromatography with amperometric detection for determinging phenolic preservatives

Liquid chromatography with amperometric detection is a rapid and sensitive method for determining commonly encountered phenolic antioxidants including 3(2)-tert-butyl-4-hydroxyanisole, tert-butylhydroquinone, n-propyl gallate, nordihydroguaiaretic acid, and 2,6-di-tert-butyl-4-hydroxymethylphenol (Ionox-100), and the antimicrobial parabens, in a variety of commercial products. Sample extracts are chromatographed directly with few interferences on the reverse phase system. The typical linear range extends from 10(-11) to 10(-6) mole of injected analyte. Pertinent experimental factors are discussed with regard to the requirements of the detector and optimizing the determination of this class of compounds.