Synthesis, characterization and evaluation of hollow molecularly imprinted polymers for Sudan I

A novel strategy was developed to prepare hollow molecularly imprinted polymers (HMIPs) with thin solid shells, in which a soft polystyrene core and a hard inner shell of SiO2 were introduced; this strategy combined surface molecular imprinting of Sudan I and in situ polymerization. The HMIPs possessed good morphological stability without deformation or breakage owing to the existence of SiO2. The thin imprinted coating (50 nm) of HMIPs ensured a faster mass transfer and a higher efficiency of active site utilization during adsorption. Moreover, the HMIPs were successfully applied as a solid-phase extraction (SPE) sorbent for the selective adsorption of Sudan I in chilli powder samples, and satisfactory recoveries were obtained in the range of 95-108% with spiked samples.