Efficient solid-phase microextraction of twelve halogens-containing environmental hormones from fruits and vegetables by triazine-based conjugated microporous polymer coating

A triazine-based conjugated microporous polymer (TCMP) was generated by introduced 1, 3, 5-triazine into conjugated microporous polymer network via Friedel-Crafts reaction. Under the optimum synthesis conditions, the obtained TCMP has a loose and porous structure. It was then used as a fiber coating material for solid-phase microextraction (SPME) of halogens-containing environmental hormones. It showed a strong adsorption capability due to the halogen bond, electrostatic, π-π stacking and hydrophobicity interactions. An analytical method combining the TCMP coated fiber-based SPME with gas chromatography-electron capture detection was developed to determine twelve halogens-containing environmental hormones in vegetable and fruit samples. A wide linear range (0.07-100.0 ng g-1) with the determination coefficients in the range of 0.9907-0.9996 and low limits of detection (0.02-0.04 ng g-1, S/N = 3) were achieved under optimized experimental conditions. The applicability of the established method was evaluated by the determination of the environmental hormones from three different fruit samples (apple, nectarine and pear) and five vegetable samples (Chinese cabbage, pakchoi, baby cabbage, rape and round lettuce). The resulting relative recoveries ranged from 76.6% to 123% with the relative standard deviations less than 10%. This research demonstrates the application potential of the TCMP coated fiber in the analysis of the halogens-containing environmental hormones in real vegetable and fruit samples.