Synthesis of molecularly imprinted polymer adsorbents for solid‐phase extraction of strobilurin fungicides from agricultural products

Abstract

Molecularly imprinted polymers for strobilurin fungicides were prepared by precipitation polymerization employing azoxystrobin as template molecular together with methacrylic acid monomer and trimethylolpropane triacrylate cross-linker.Morphological characterization showed molecularly imprinted polymers were uniform spherical particles with about 0.2 μm in diameter, while the morphologies of nonimprinted polymers were irregular bulk. The equilibrium binding and selective experiments proved that molecularly imprinted polymers possessed a higher affinity toward four fungicides compared to nonimprinted polymers and heterogeneous binding sites were found in the molecularly imprinted polymers. Molecularly imprinted solid-phase extraction conditions, including sample loading solvents, selective washing, and elution solvents, were carefully optimized. The developed method showed good recoveries (70.0-114.0%) with relative standard deviations in range of 1.0-9.8% (n = 3) for samples (cucumber and peach) spiked at three different levels (10, 50, and 100 μg/ kg). The detection limit (signal/noise = 3) ranged from 0.01 to 0.08 μg/kg. The results demonstrated good potential use of this convenient and highly efficient method for determining trace strobilurin fungicides in agricultural products. K E Y W O R D Sagricultural products, molecularly imprinted polymers, solid-phase extraction, strobilurin fungicides

Solid-Phase Extraction of Active Compounds from Natural Products by Molecularly Imprinted Polymers: Synthesis and Extraction Parameters

“…In a precipitation polymerization, the morphology was discussed by Li et al [93]. The SEM analysis shows that spherical particles were obtained with a diameter of around 0.2 µm for the MIPs, while an interconnected-irregular bulk was observed in the NIPs.…”

“…Li et al [93] observed absorptions in the azoxystrobin molecule of the MIPs correlated to the stretching vibration of -CN on the aromatic ring and the plane bending vibration of -CH on the aromatic ring at 2230 and 1560 cm −1 , respectively, while the carboxyl groups in MAA were assigned at 1731 cm −1 . Two distinct peaks of MIPs at 2230 cm −1 and 1560 cm −1 disappeared after washing with HAc-MeOH, suggesting that the azoxystrobin template was removed.…”

Imprinting Technology for Effective Sorbent Fabrication: Current State-of-Art and Future Prospects

“…The molecularly imprinted sorbents were utilized in the food analysis for determination of antibiotics such as norfloxacin [121] or cephalexin in pork [122], tetracycline in chicken [123], aminoglycosides (streptomycin, kanamycin, and gentamycin) in various milk samples [124], chloramphenicol in honey [125], zearalenone in wheat [126], estrogens (estrone, estriol, and estragon) in milk [127] or in cucumber, milk powder and grass carp samples [128], sulfonamides such as sulfamethoxazole in milk [129], imidacloprid [130] or kaempherol in apples [131], patulin in apple juice [132], hesperidin in lime juice [133], strobilurin in peach [134], carbendazim in orange [135], dopamine in bananas [136], fenoxycarb in mussels [137], phenylarsonic compounds in chicken and pork samples [138], or organochlorine fungicides in ginseng samples [139], acrylamide in biscuits [140], bisphenoles A [141] as well as F and S (on imprinted commercial sorbent-Affinimip ® ) [142], and quercetin in onion [143]. The imprinted sorbents were also used for selective extraction of plant ingredients, such as rosmarinic acid from Rosmarinus officinalis L. [144], tannins from the barks of Anadenanthera macrocarpa var.…”

Recent advances and applications of molecularly imprinted polymers in solid‐phase extraction for real sample analysis

“…The precipitation polymerization is another frequently used approach to prepare MIP particles or microspheres for food samples [24,29,38,52–54,88–93]. As an example, Khan et al.…”