Sustainable dual-template magnetic molecularly imprinted polymer for ultra-trace simultaneous determination of morin and luteolin in complex matrices

A newly designed dual-template magnetic molecularly imprinted polymer (MMIP) integrated with ultrasound-assisted dispersive solid-phase microextraction (UA‑DSPME) was developed for the simultaneous determination of morin and luteolin in herbal products and water samples. The MMIP displayed outstanding selectivity (imprinting factors: 3.26–3.44; selectivity coefficient (β) > 3.0 relative to caffeic, chlorogenic, and rosmarinic acids) and enhanced sorption capacity (84.1–86.3 mg g -1 ), surpassing the sorption capacity of the non-imprinted polymer (MNIP) by 3.4-fold. The method provided ultra-trace detection limits of 0.42 ng mL -1 for luteolin and 0.53 ng mL -1 for morin, with limits of quantification (LOQs) of 1.41–1.78 ng mL -1 , and a wide linear ranges of 10–6000 ng mL -1 for luteolin and 15–6000 ng mL -1 for morin. High extraction recoveries (93.6–106.5%) and good precision (RSDs: 1.3–5.6%) demonstrated the robustness of the method in complex matrices. Importantly, the MMIP retained more than 94% of its extraction efficiency after five reuse cycles. Green analytical metrics (AGREE: 0.74, AGREEprep: 0.67, BAGI: 70.0) further validated the method’s sustainability by minimizing solvent consumption (0.20 mL of methanol per analysis), eliminating centrifugation steps, and achieving a 94% reduction in environmental impact compared with conventional SPE. These scores confirm the dual-template MMIP-D-SPME approach as a benchmark for green multi-analyte analysis, consistent with the twelve principles of green chemistry while maintaining ultra-trace sensitivity and robustness in complex matrices. Application of the proposed method to six medicinal plant samples and environmental water sources successfully quantified native morin (19.14–320.4 ng mL -1 ) and luteolin (19.61–335.2 ng mL -1 ), with spike recoveries ranging from 93.6% to 106.5%. This dual-template approach enables the simultaneous, interference-free detection of structurally similar flavonoids, a capability that cannot be achieved using single-analyte methods, positioning the MMIP-UA‑DSPME method as an eco-friendly, high-throughput platform for multi-compound analysis in pharmaceutical quality control.