Determination of Phenolic Environmental Estrogens in Eggs by High Performance Liquid Chromatography and Sample Preparation with Matrix Solid Phase Dispersion

Abstract

Simultaneous determination of the phenolic environmental estrogens in egg by high performance liquid chromatography (HPLC) and sample preparation with matrix solid phase dispersion (MSPD) was developed. A 0.2 g of sample was placed into an agate mortar and gently blended with 0.4 g florisil to obtain a homogeneous mixture. This mixture was introduced into a Teflon cartridge. The estrogens fraction was eluted from the cartridge with dichloromethane. The residue was dissolved with methanol after evaporation of the solvent (dichloromethane). The estrogens (bisphenol A, diethylstilbestrol and nonylphenol) were separated on a ZORBAX stable bound (4.6 mm × 50 mm, 1.8 μm) C₁₈ column with acetonitrile and water (80:20) as the mobile phase and detected with photodiode array detector. This method provides good reproducibility and sensitivity for the quantification of bisphenol A, diethylstilbestrol and nonylphenol. The relative standard derivations of overall intra-day variations were less than 2.6 % and the relative standard deriva-tions of inter-day variations were less than 2.9 %. The standard recoveries (three different concentrations of markers: 0.5, 1.0 and 5.0 μg) were ranged from 93-104 %.