JOURNAL OF CHROMATOGRAPHY, no.1713, pp.1-10, 2024 (SCI-Expanded)
A dummy molecularly imprinted polymer-based solid-phase extraction (SPE) sorbent was used for the selective
extraction of some phthalate monoesters, monoethyl phthalate (MEP), monobutyl phthalate (MnBP) and mono-
(2-ethylhexyl) phthalate (MEHP) in urine prior to gas-chromatography-mass spectrometry (GC-MS) analysis.
Diethyl phthalate (DEP), a phthalate ester, was successfully used as a dummy template to prepare selective
sorbent for MEP, MnBP, and MEHP extraction. DEP-imprinted poly(ethylene glycol dimethacrylate N-methacryloyl-L-tryptophan methyl ester) (DPEMT) microbeads were synthesized by suspension polymerization and
characterized by Fourier Transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM) and
Brunauer Emmet Teller (BET) analysis. The critical parameters (i.e., pH, sorbent amount, ionic strength, sample
volume, elution solvent) affecting the extraction performance of the DPEMT-SPE sorbent were optimized. Under
optimum conditions, good linearities were obtained in the concentration range of 4 to 60 ng/mL with determination coefficients (R2
) of greater than 0.9959. The developed SPE method provided low limits of detection
(LOD) of 0.05–1.20 ng/mL and limits of quantification (LOQ) of 0.18–4.01 ng/mL with relative standard deviations (RSDs) of less than 8.95 % for intra- and inter-day analyses. The proposed SPE method was used to
analyze phthalate monoesters in spiked urine samples, and recoveries of 97.45–109.26 % were obtained.
DPEMT-SPE sorbent was reused for 15 times without any losses of performance. Consequently, a highly selective
and sensitive SPE method based on a dummy molecularly imprinted polymer combined with GC-MS was successfully developed to monitor human phthalate exposure via urine samples.