Unified Reversed‐Phase Method for the Determination of Di (2‐Ethylhexyl) Phthalate and Its Major Metabolite, Mono (2‐Ethylhexyl) Phthalate, in Biological Samples

Abstract

A UV detector at 235 nm and an Alltech Altima C₁₈ column (150×4.6 mm and 5 micron) were used to develop a high performance liquid chromatographic method to determine Di (2‐ethylhexyl) phthalate [DEHP] and its metabolite mono (2‐ethylhexyl) phthalate [MEHP] in biological samples. A gradient time of 8 min and a gradient range of 60–100% acetonitrile (ACN) at pH 3.0, with a segmented flow rate gradient, were found to be optimum conditions. These conditions resulted in retention times of 4.2 and 7.1 min for MEHP and DEHP, respectively. The estimated limits of detection (LOD) and quantitation (LOQ) for DEHP were 1.37 and 4.8 µg/mL, respectively. For MEHP, LOD, and LOQ were 0.57 and 2.4 µg/mL, respectively. The developed method was applied to determine DEHP and its metabolite MEHP in blood plasma, liver, kidney, brain, and testis samples.

Keywords:

• DEHP
• MEHP
• HPLC‐UV
• Biological samples