Preparation of selective magnetic dispersive solid-phase sorbent and its application for recognition clenbuterol from bovine urine

A new kind of selective magnetic dispersive solid-phase sorbent based on multiple Fe3O4 nanospheres as the core structure and molecular imprinted material as the shell structure was synthesized with tert-butylamine and 2-chloroaniline as the templates. The obtained multicore–shell-structured sorbent was spherical (diameter distribution 25–90 μm) with porous morphologies, thus incorporating strong magnetic properties and specific molecular recognition coupled with rapid adsorption and dynamic equilibrium. The sorbent was applied for rapid and selective screening of clenbuterol (CLB) in bovine urine samples. Good linearity was obtained in the range 1.25–200 ng mL−1 with the average recovery at three spiked levels ranging from 91.4% to 105.3%. The proposed method significantly improved the purification and extraction efficiency of CLB in urine samples and eliminated the effect of template leakage during quantitative analysis.