Selective solid-phase extraction and determination of profenofos from food and water samples using surface molecularly-imprinted bentonite

In this study, a surface-imprinted molecularly imprinted polymer (MIP) was prepared on bentonite (BNT) to create a selective solid-phase extraction (SPE) sorbent for detecting profenofos (PFF), a commonly used organophosphorus pesticide. The MIP–BNT material was produced through surface-initiated free-radical polymerization, and structural analyses confirmed the presence of specific binding sites, uniform morphology, and an enhanced surface area. Adsorption behavior followed a pseudo-second-order kinetic model (R 2 = 0.9965), while equilibrium data showed strong agreement with the Langmuir isotherm (R 2 = 0.9979), indicating monolayer adsorption. Key SPE parameters—including pH, sorbent amount, desorption time, and eluent volume—were systematically optimized. The final conditions (pH 6.0, 10 mg sorbent, 25 min desorption, 150 µL eluent) ensured high recovery and repeatability. When coupled with UV–vis spectrophotometry, the optimized MIP-SPE method provided a wide linear range (0.1–270 µM), a low detection limit (0.03 µM), and stable performance over at least eight reuse cycles. Recovery experiments conducted in food and water matrices yielded values between 94.01 % and 100.42 %, with RSD values below 5 %, and results were consistent with HPLC measurements. Overall, the developed approach presents a selective, cost-effective, and environmentally friendly alternative for routine PFF analysis. • A novel molecularly-imprinted bentonite was prepared for profenofos extraction. • The method allows selective solid-phase extraction from food and water samples. • A low detection limit of 0.0334 µM was achieved with high reproducibility. • The sorbent showed excellent reusability over eight consecutive extraction cycles.