Superparamagnetic surface molecularly imprinted nanoparticles for sensitive solid-phase extraction of tramadol from urine samples

► An MIP (MMIPNPs) was synthesized by precipitation polymerization using tramadol as template. ► The modified nanoparticles were characterized by different methods. ► The synthesized MIP was used to the preconcentration and determination of tramadol. ► Kinetics parameters indicated the second-order mechanism. ► The MMIPNPs are highly monodisperse and magnetically separable.