Computer simulation-guided template selection for a molecularly imprinted polymer for selective trifluralin adsorption

Abstract

To meet selective adsorption toward trifluralin, a novel molecularly imprinted polymer (MIP) was fabricated by the dummy template molecular imprinting technology. First, computational simulation was performed to select a suitable dummy template, 3,5-dinitro-4-methylbenzoic acid (T1), based on the maximum basis set superposition error (BSSE)-corrected binding interaction energy (ΔE) of the monomer N-vinylpyrrolidone (NVP)-T1 complex and its structural overlap with trifluralin. Then, the MIP was prepared via the bulk polymerization. The adsorption experiments showed the MIP exhibited a trifluralin adsorption capacity of 5.1 mg g⁻¹, an imprinting factor (IF) of 2.2, and short adsorption equilibrium time of 5 min. The adsorption of trifluralin conformed to the Freundlich adsorption (R² = 0.985) and pseudo-second-order model (R² = 0.999). In addition, the MIP exhibited selectivity to trifluralin over other adsorbents, including structural analogs (pendimethalin and oryzalin), pesticide (carbendazim), and nitrocompounds (nitrofurantoin, furazolidone, and furaltadone), with the selectivity factor (β) in the range of 1.2–3.0, respectively. In trifluralin/oryzalin mixture, the IF toward oryzalin was still as high as 1.9. The removal rate of the MIP to trifluralin in environmental water samples ranged from 90.08% to 99.04%. This study provides theoretical and experimental insights for the preparation of MIP using dummy templates.