Magnetic dummy-template molecularly imprinted polymers as selective sorbents for geosmin enrichment from water...

In the present work, core-shell Fe₃O₄@SiO₂@DMIPs were prepared using a dummy-template imprinting strategy and applied as extraction sorbents for the selective enrichment of geosmin (GSM) from water samples. The resulting Fe₃O₄@SiO₂@DMIPs showed an adsorption capacity of 6.85 mg g^-1, reached adsorption equilibrium within 75 min, and could be magnetically separated within 30 s. Compared with the corresponding non-imprinted polymers, the imprinted sorbents showed enhanced adsorption toward GSM and preferential recognition of GSM over 2-methylisoborneol. After six adsorption-desorption cycles, the adsorption performance decreased by only 9.36%, indicating acceptable reusability. When applied to magnetic dispersive solid-phase extraction coupled with GC-MS, the Fe₃O₄@SiO₂@DMIPs achieved recoveries of 83.1-90.2% for spiked water samples, with relative standard deviations lower than 7.4%, and provided limits of detection and quantitation of 0.034 and 0.115 mg L^-1, respectively. These results suggest that Fe₃O₄@SiO₂@DMIPs could be used as selective pretreatment sorbents for GSM enrichment and may provide a useful reference for developing imprinting-based extraction materials.