An efficient mixed-mode strong anion-exchange adsorbent based on functionalized polyethyleneimine for simultaneous solid phase extraction and purification of bisphenol analogues and monoalkyl phthalate esters in human urine

Abstract

In this study, a mixed-mode strong anion-exchange (MAX) adsorbent was developed based on amine-functionalized poly(divinylbenzene) (PDVB) functionalized with polyethyleneimine (PEI) followed by quaternization with glycidyl phenyl ether (named as PDVB-QPEI). Fourier Transform Infrared spectroscopy and nitrogen adsorption–desorption experiments indicated that the PDVB-QPEI was successfully synthesized with a BET specific surface area (SBET) of 118.5 m2 g−1, pore volume of 0.37 cm3 g−1, and pore size of 16.41 nm. High ion-exchange capacity (IEC) of 0.57 mmol g−1 was achieved. The important parameters influencing SPE efficiency were optimized, including adsorbent mass, pH of the sample, type and volume of washing solvent and eluent. The practical capability of this novel PDVB-QPEI MAX adsorbent was tested for solid phase extraction and purification of bisphenol analogues and monoalkyl phthalate esters (MPEs) in urine samples. Outstanding extraction and cleanup efficiency were achieved simultaneously for urine samples due to high selectivity of the PDVB-QPEI adsorbent for bisphenol analogues and MPEs. Recovery values ranged from 80.1% to 102.4% with precision (relative standard devition, n = 3) below 6% for these blank urine samples spiked at different levels. The limit of detections (LODs) obtained by HPLC-DAD were in the range of 3–9 ng mL−1. The PDVB-QPEI is superior to commercial adsorbents (Oasis HLB, C18 and Oasis MAX). These results demonstrated the great potential application of the PDVB-QPEI adsorbent in routine analysis of bisphenol analogues and MPEs in complex samples.