An analytical method for estrogens in milk powder by pseudo template imprinted polymer coated fiber coupled with HPLC

Abstract

This paper reports a novel molecularly imprinted polymer (MIP) coated fiber for extraction of estrogens. A rationally designed 17-ethylestradiol (ED) that exhibits resemblance to estrogens has been synthesized and used as a pseudo template. A DFT-based computational simulation method was proposed to choose the best functional monomer. The MIP coated fiber was fabricated by using silica fiber as substrate, ED as pseudo template, 2-(trifluoromethyl) acrylic acid (TFMAA) and acrylic acid (AA) as composite functional monomers, and ethylene glycol dimethacrylate (EGDMA) as the cross-linking agent. A series of investigations indicated that the MIP coated fiber possessed excellent stability, rebinding capacity, selectivity and kinetics. An analytical method for the determination of estrogens in milk powder samples, combining molecularly imprinted solid phase micro-extraction (MISPME) with high performance liquid chromatography-ultraviolet (HPLC-UV), was developed. The limits of detection were in the range of 0.83–2.5 ng mL⁻¹, the recoveries were 86–92%, 88–97%, 90–93% and 95–99% with RSD < 6.7% for estrone, 17β-estradiol, estriol and 17-ethynylestradiol, respectively.