Methacrylic acid:divinylbenzene (MAA:DVB) copolymer for mixed-mode extraction of emerging contaminants from environmental waters

Background The widespread occurrence of emerging contaminants (ECs) in environmental waters presents analytical challenges due to their structural diversity, varied physicochemical properties, and ultra-trace concentrations. Solid-phase extraction (SPE) remains a critical step in sample preparation, but commercial sorbents often lack the versatility needed to simultaneously extract diverse analytes. There is a growing need for cost-effective, customizable sorbents with enhanced selectivity and extraction efficiency. Results A novel hypercrosslinked methacrylic acid:divinylbenzene (MAA:DVB) copolymer was developed as a mixed-mode SPE sorbent, combining hydrophobic and weak cation-exchange functionalities. The polymer was synthesized under varying conditions to tune its physical (rigidity, permeability) and chemical (retention capacity) properties, and characterized by scanning electron microscopy (SEM) and Fourier-transform infrared (FTIR) spectroscopy. A factorial experimental design was used to optimize both polymer synthesis and SPE conditions, such as sample pH, elution solvent, and volumes. The optimum method, coupled with ultra-high performance liquid chromatography tandem mass spectrometry (UHPLC-MS/MS), achieved excellent analytical performance: linearity (R 2 > 0.991), low limits of quantification (50 ng L -1 ), and good precision (RSD < 15%). The method was successfully applied to real water samples, detecting various ECs including pharmaceuticals (azithromycin, O-desmethylvenlafaxine, fluconazole, venlafaxine) and pesticides (imidacloprid). Significance This work demonstrates, for the first time, the application of a lab-made hypercrosslinked MAA:DVB copolymer as a chemically tunable and cost-effective mixed-mode SPE sorbent for broad-spectrum EC extraction. The optimized method provides an efficient alternative to commercial sorbents, significantly enhancing the monitoring of ECs in complex environmental matrices.