Berberine-based hypercrosslinked polymer: Advanced solid-phase microextraction for high-throughput analysis of aristolochic acids in environmental water and herbal plants

In this study, a novel berberine based anion-exchanged hypercrosslinked polymer (BBR-HCPs) was synthesized via Friedel-Crafts alkylation using dimethoxymethane as a cross-linking agent. The proposed BBR-HCPs polymer exhibited excellent adsorption capacities for aristolochic acids (AAs). Moreover, there are various interactions such as hydrophobic, π-π stacking, hydrogen bonding, and electrostatic interactions between BBR-HCPs and AAs. A solid phase microextraction (SPME) coating, prepared with BBR-HCPs as the sorbent and polyacrylonitrile (PAN) as the binder, was applied for the determination of AAs in herbal plants using a 24-well plate for high-throughput, with instrumental analysis carried out via high performance liquid chromatography with diode array detector (HPLC-DAD). The optimized and validated BBR-HCPs-SPME/HPLC-DAD method exhibited excellent linearity over range of 5–400 ng mL⁻¹ with R² > 0.9974. Detection limits (S/N = 3) for AAs were found to be 0.03–0.150 ng mL⁻¹, with recoveries ranging from 82.6 to 117.8 % and relative standard deviations (RSDs) less than 10.49 %. This study underscores the potential of BBR-HCPs as a promising adsorbent for selective extraction and enrichment of AAs while introducing a reliable novel strategy for monitoring trace amounts of AAs in water and herbal plant samples.