Core–Shell Magnetic Molecularly Imprinted Polymers as Sorbent for Sulfonylurea Herbicide Residues

Abstract

Sulfonylurea herbicides are widely used at lower dosage for controlling broad-leaf weeds and some grasses in cereals and economic crops. It is important to develop a highly efficient and selective pretreatment method for analyzing sulfonylurea herbicide residues in environments and samples from agricultural products based on magnetic molecularly imprinted polymers (MIPs). The MIPs were prepared by a surface molecular imprinting technique especially using the vinyl-modified Fe3O4@SiO2 nanoparticle as the supporting matrix, bensulfuron-methyl (BSM) as the template molecule, methacrylic acid (MAA) as a functional monomer, trimethylolpropane trimethacrylate (TRIM) as a cross-linker, and azodiisobutyronitrile (AIBN) as an initiator. The MIPs show high affinity, recognition specificity, fast mass transfer rate, and efficient adsorption performance toward BSM with the adsorption capacity reaching up to 37.32 mg g(-1). Furthermore, the MIPs also showed cross-selectivity for herbicides triasulfuron (TS), prosulfuron (PS), and pyrazosulfuron-ethyl (PSE). The MIP solid phase extraction (SPE) column was easier to operate, regenerate, and retrieve compared to those of C18 SPE column. The developed method showed highly selective separation and enrichment of sulfonylurea herbicide residues, which enable its application in the pretreatment of multisulfonylurea herbicide residues.

Preparation of stoichiometric molecularly imprinted polymer coatings on magnetic particles for the selective extraction of auramine O from water

“…It was observed that the vibration peak at 1630 cm −1 corresponding to the stretching vibration of C=C in MPS further proved that SiO 2 @Fe 3 O 4 was successfully grafted with MPS. Those results are consistent with that of other researches [40,41].…”

“…The adsorption capacity of the MMIPs for AO is the highest, which means that template molecule has a higher selective affinity to the MMIPs than its analogues [25]. It may be related to the size and functional groups of recognition sites, and the interaction is mainly due to hydrogen bond and ionic interaction [39,40]. Low adsorption capacity of MMIPs for chrysoidine was observed due to the different structure in comparison with AO and AOHCl, and the adsorption capacity of MNIPs for AO is almost the same with AOHCl, but much higher than chrysoidine due to the structural difference.…”

Magnetic dispersive micro solid-phase extraction and gas chromatography determination of organophosphorus pesticides in strawberries

“…Among them, there can be found pyrethroids [46,60], carbamates [61], organochlorine pesticides (OCPs) [62,63] or OPPs [45, 64,65], phenylurea [53] and sulfonylurea herbicides [66] although nanomaterials have also been suitability applied for pesticide multiresidues extraction [48,49,51].…”

Ultra-Stable UiO-66 Involved Molecularly Imprinted Polymers for Specific and Sensitive Determination of Tyramine Based on Quartz Crystal Microbalance Technology

“…MIPs are workable to maximize the selectivity and sensitivity of detection sensors as recognition elements [4]. MIPs are widely used in the environmental [12], agricultural [13], food science [14], and pharmaceutical industries [15]. With the development of science and technology and the appearance of advanced instruments, the relatively homogeneous MIPs could not satisfy the growing technological requirements [16].…”